From patchwork Tue Jul 14 12:08:03 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662673 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id CC3BC13B4 for ; Tue, 14 Jul 2020 12:18:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BC901223C6 for ; Tue, 14 Jul 2020 12:18:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728111AbgGNMKh (ORCPT ); Tue, 14 Jul 2020 08:10:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60588 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726354AbgGNMKg (ORCPT ); Tue, 14 Jul 2020 08:10:36 -0400 Received: from theia.8bytes.org (8bytes.org [IPv6:2a01:238:4383:600:38bc:a715:4b6d:a889]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 76084C061794; Tue, 14 Jul 2020 05:10:36 -0700 (PDT) Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id C708A293; Tue, 14 Jul 2020 14:10:33 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , Tom Lendacky , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 01/75] KVM: SVM: Add GHCB definitions Date: Tue, 14 Jul 2020 14:08:03 +0200 Message-Id: <20200714120917.11253-2-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Tom Lendacky Extend the vmcb_safe_area with SEV-ES fields and add a new 'struct ghcb' which will be used for guest-hypervisor communication. Signed-off-by: Tom Lendacky Signed-off-by: Joerg Roedel --- arch/x86/include/asm/svm.h | 45 +++++++++++++++++++++++++++++++++++++- arch/x86/kvm/svm/svm.c | 2 ++ 2 files changed, 46 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/svm.h b/arch/x86/include/asm/svm.h index 8a1f5382a4ea..9a3e0b802716 100644 --- a/arch/x86/include/asm/svm.h +++ b/arch/x86/include/asm/svm.h @@ -200,13 +200,56 @@ struct __attribute__ ((__packed__)) vmcb_save_area { u64 br_to; u64 last_excp_from; u64 last_excp_to; + + /* + * The following part of the save area is valid only for + * SEV-ES guests when referenced through the GHCB. + */ + u8 reserved_7[104]; + u64 reserved_8; /* rax already available at 0x01f8 */ + u64 rcx; + u64 rdx; + u64 rbx; + u64 reserved_9; /* rsp already available at 0x01d8 */ + u64 rbp; + u64 rsi; + u64 rdi; + u64 r8; + u64 r9; + u64 r10; + u64 r11; + u64 r12; + u64 r13; + u64 r14; + u64 r15; + u8 reserved_10[16]; + u64 sw_exit_code; + u64 sw_exit_info_1; + u64 sw_exit_info_2; + u64 sw_scratch; + u8 reserved_11[56]; + u64 xcr0; + u8 valid_bitmap[16]; + u64 x87_state_gpa; +}; + +struct __attribute__ ((__packed__)) ghcb { + struct vmcb_save_area save; + u8 reserved_save[2048 - sizeof(struct vmcb_save_area)]; + + u8 shared_buffer[2032]; + + u8 reserved_1[10]; + u16 protocol_version; /* negotiated SEV-ES/GHCB protocol version */ + u32 ghcb_usage; }; static inline void __unused_size_checks(void) { - BUILD_BUG_ON(sizeof(struct vmcb_save_area) != 0x298); + BUILD_BUG_ON(sizeof(struct vmcb_save_area) != 1032); BUILD_BUG_ON(sizeof(struct vmcb_control_area) != 256); + BUILD_BUG_ON(sizeof(struct ghcb) != 4096); } struct __attribute__ ((__packed__)) vmcb { diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index c0da4dd78ac5..af6dc22437c1 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -4099,6 +4099,8 @@ static struct kvm_x86_init_ops svm_init_ops __initdata = { static int __init svm_init(void) { + __unused_size_checks(); + return kvm_init(&svm_init_ops, sizeof(struct vcpu_svm), __alignof__(struct vcpu_svm), THIS_MODULE); } From patchwork Tue Jul 14 12:08:04 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662669 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 8608A13A4 for ; Tue, 14 Jul 2020 12:18:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 75E8D2068F for ; Tue, 14 Jul 2020 12:18:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728130AbgGNMKi (ORCPT ); Tue, 14 Jul 2020 08:10:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60592 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726823AbgGNMKh (ORCPT ); Tue, 14 Jul 2020 08:10:37 -0400 Received: from theia.8bytes.org (8bytes.org [IPv6:2a01:238:4383:600:38bc:a715:4b6d:a889]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E6450C08C5C1; Tue, 14 Jul 2020 05:10:36 -0700 (PDT) Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 5C42F2C2; Tue, 14 Jul 2020 14:10:34 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 02/75] KVM: SVM: Add GHCB Accessor functions Date: Tue, 14 Jul 2020 14:08:04 +0200 Message-Id: <20200714120917.11253-3-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Building a correct GHCB for the hypervisor requires setting valid bits in the GHCB. Simplify that process by providing accessor functions to set values and to update the valid bitmap. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/svm.h | 61 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 61 insertions(+) diff --git a/arch/x86/include/asm/svm.h b/arch/x86/include/asm/svm.h index 9a3e0b802716..0420250b008b 100644 --- a/arch/x86/include/asm/svm.h +++ b/arch/x86/include/asm/svm.h @@ -341,4 +341,65 @@ struct __attribute__ ((__packed__)) vmcb { #define SVM_CR0_SELECTIVE_MASK (X86_CR0_TS | X86_CR0_MP) +/* GHCB Accessor functions */ + +#define DEFINE_GHCB_INDICES(field) \ + u16 idx = offsetof(struct vmcb_save_area, field) / 8; \ + u16 byte_idx = idx / 8; \ + u16 bit_idx = idx % 8; \ + BUILD_BUG_ON(byte_idx > ARRAY_SIZE(ghcb->save.valid_bitmap)); + +#define GHCB_SET_VALID(ghcb, field) \ + { \ + DEFINE_GHCB_INDICES(field) \ + (ghcb)->save.valid_bitmap[byte_idx] |= BIT(bit_idx); \ + } + +#define DEFINE_GHCB_SETTER(field) \ + static inline void \ + ghcb_set_##field(struct ghcb *ghcb, u64 value) \ + { \ + GHCB_SET_VALID(ghcb, field) \ + (ghcb)->save.field = value; \ + } + +#define DEFINE_GHCB_ACCESSORS(field) \ + static inline bool ghcb_is_valid_##field(const struct ghcb *ghcb) \ + { \ + DEFINE_GHCB_INDICES(field) \ + return !!((ghcb)->save.valid_bitmap[byte_idx] \ + & BIT(bit_idx)); \ + } \ + \ + static inline void \ + ghcb_set_##field(struct ghcb *ghcb, u64 value) \ + { \ + GHCB_SET_VALID(ghcb, field) \ + (ghcb)->save.field = value; \ + } + +DEFINE_GHCB_ACCESSORS(cpl) +DEFINE_GHCB_ACCESSORS(rip) +DEFINE_GHCB_ACCESSORS(rsp) +DEFINE_GHCB_ACCESSORS(rax) +DEFINE_GHCB_ACCESSORS(rcx) +DEFINE_GHCB_ACCESSORS(rdx) +DEFINE_GHCB_ACCESSORS(rbx) +DEFINE_GHCB_ACCESSORS(rbp) +DEFINE_GHCB_ACCESSORS(rsi) +DEFINE_GHCB_ACCESSORS(rdi) +DEFINE_GHCB_ACCESSORS(r8) +DEFINE_GHCB_ACCESSORS(r9) +DEFINE_GHCB_ACCESSORS(r10) +DEFINE_GHCB_ACCESSORS(r11) +DEFINE_GHCB_ACCESSORS(r12) +DEFINE_GHCB_ACCESSORS(r13) +DEFINE_GHCB_ACCESSORS(r14) +DEFINE_GHCB_ACCESSORS(r15) +DEFINE_GHCB_ACCESSORS(sw_exit_code) +DEFINE_GHCB_ACCESSORS(sw_exit_info_1) +DEFINE_GHCB_ACCESSORS(sw_exit_info_2) +DEFINE_GHCB_ACCESSORS(sw_scratch) +DEFINE_GHCB_ACCESSORS(xcr0) + #endif From patchwork Tue Jul 14 12:08:05 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662675 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 684BA13B4 for ; Tue, 14 Jul 2020 12:18:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 594302068F for ; Tue, 14 Jul 2020 12:18:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729056AbgGNMSR (ORCPT ); Tue, 14 Jul 2020 08:18:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60596 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727909AbgGNMKh (ORCPT ); Tue, 14 Jul 2020 08:10:37 -0400 Received: from theia.8bytes.org (8bytes.org [IPv6:2a01:238:4383:600:38bc:a715:4b6d:a889]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 52CA8C061794; Tue, 14 Jul 2020 05:10:37 -0700 (PDT) Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id D82C32EC; Tue, 14 Jul 2020 14:10:34 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , Borislav Petkov , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 03/75] KVM: SVM: Use __packed shorthand Date: Tue, 14 Jul 2020 14:08:05 +0200 Message-Id: <20200714120917.11253-4-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Borislav Petkov Use the shorthand to make it more readable. No functional changes. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/svm.h | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/arch/x86/include/asm/svm.h b/arch/x86/include/asm/svm.h index 0420250b008b..af91ced0f370 100644 --- a/arch/x86/include/asm/svm.h +++ b/arch/x86/include/asm/svm.h @@ -150,14 +150,14 @@ struct __attribute__ ((__packed__)) vmcb_control_area { #define SVM_NESTED_CTL_NP_ENABLE BIT(0) #define SVM_NESTED_CTL_SEV_ENABLE BIT(1) -struct __attribute__ ((__packed__)) vmcb_seg { +struct vmcb_seg { u16 selector; u16 attrib; u32 limit; u64 base; -}; +} __packed; -struct __attribute__ ((__packed__)) vmcb_save_area { +struct vmcb_save_area { struct vmcb_seg es; struct vmcb_seg cs; struct vmcb_seg ss; @@ -231,9 +231,9 @@ struct __attribute__ ((__packed__)) vmcb_save_area { u64 xcr0; u8 valid_bitmap[16]; u64 x87_state_gpa; -}; +} __packed; -struct __attribute__ ((__packed__)) ghcb { +struct ghcb { struct vmcb_save_area save; u8 reserved_save[2048 - sizeof(struct vmcb_save_area)]; @@ -242,7 +242,7 @@ struct __attribute__ ((__packed__)) ghcb { u8 reserved_1[10]; u16 protocol_version; /* negotiated SEV-ES/GHCB protocol version */ u32 ghcb_usage; -}; +} __packed; static inline void __unused_size_checks(void) @@ -252,11 +252,11 @@ static inline void __unused_size_checks(void) BUILD_BUG_ON(sizeof(struct ghcb) != 4096); } -struct __attribute__ ((__packed__)) vmcb { +struct vmcb { struct vmcb_control_area control; u8 reserved_control[1024 - sizeof(struct vmcb_control_area)]; struct vmcb_save_area save; -}; +} __packed; #define SVM_CPUID_FUNC 0x8000000a From patchwork Tue Jul 14 12:08:06 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662667 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4092713A4 for ; Tue, 14 Jul 2020 12:18:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 32AFC22460 for ; Tue, 14 Jul 2020 12:18:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728298AbgGNMSB (ORCPT ); Tue, 14 Jul 2020 08:18:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60598 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728144AbgGNMKi (ORCPT ); Tue, 14 Jul 2020 08:10:38 -0400 Received: from theia.8bytes.org (8bytes.org [IPv6:2a01:238:4383:600:38bc:a715:4b6d:a889]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E6CC2C061755; Tue, 14 Jul 2020 05:10:37 -0700 (PDT) Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 6620B2F9; Tue, 14 Jul 2020 14:10:35 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , Tom Lendacky , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 04/75] x86/cpufeatures: Add SEV-ES CPU feature Date: Tue, 14 Jul 2020 14:08:06 +0200 Message-Id: <20200714120917.11253-5-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Tom Lendacky Add CPU feature detection for Secure Encrypted Virtualization with Encrypted State. This feature enhances SEV by also encrypting the guest register state, making it in-accessible to the hypervisor. Signed-off-by: Tom Lendacky Signed-off-by: Joerg Roedel --- arch/x86/include/asm/cpufeatures.h | 1 + arch/x86/kernel/cpu/amd.c | 3 ++- arch/x86/kernel/cpu/scattered.c | 1 + 3 files changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h index 02dabc9e77b0..069a774f6d57 100644 --- a/arch/x86/include/asm/cpufeatures.h +++ b/arch/x86/include/asm/cpufeatures.h @@ -234,6 +234,7 @@ #define X86_FEATURE_EPT_AD ( 8*32+17) /* Intel Extended Page Table access-dirty bit */ #define X86_FEATURE_VMCALL ( 8*32+18) /* "" Hypervisor supports the VMCALL instruction */ #define X86_FEATURE_VMW_VMMCALL ( 8*32+19) /* "" VMware prefers VMMCALL hypercall instruction */ +#define X86_FEATURE_SEV_ES ( 8*32+20) /* AMD Secure Encrypted Virtualization - Encrypted State */ /* Intel-defined CPU features, CPUID level 0x00000007:0 (EBX), word 9 */ #define X86_FEATURE_FSGSBASE ( 9*32+ 0) /* RDFSBASE, WRFSBASE, RDGSBASE, WRGSBASE instructions*/ diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c index d4806eac9325..7eaca090e2e8 100644 --- a/arch/x86/kernel/cpu/amd.c +++ b/arch/x86/kernel/cpu/amd.c @@ -613,7 +613,7 @@ static void early_detect_mem_encrypt(struct cpuinfo_x86 *c) * If BIOS has not enabled SME then don't advertise the * SME feature (set in scattered.c). * For SEV: If BIOS has not enabled SEV then don't advertise the - * SEV feature (set in scattered.c). + * SEV and SEV_ES feature (set in scattered.c). * * In all cases, since support for SME and SEV requires long mode, * don't advertise the feature under CONFIG_X86_32. @@ -644,6 +644,7 @@ static void early_detect_mem_encrypt(struct cpuinfo_x86 *c) setup_clear_cpu_cap(X86_FEATURE_SME); clear_sev: setup_clear_cpu_cap(X86_FEATURE_SEV); + setup_clear_cpu_cap(X86_FEATURE_SEV_ES); } } diff --git a/arch/x86/kernel/cpu/scattered.c b/arch/x86/kernel/cpu/scattered.c index 62b137c3c97a..30f354989cf1 100644 --- a/arch/x86/kernel/cpu/scattered.c +++ b/arch/x86/kernel/cpu/scattered.c @@ -41,6 +41,7 @@ static const struct cpuid_bit cpuid_bits[] = { { X86_FEATURE_MBA, CPUID_EBX, 6, 0x80000008, 0 }, { X86_FEATURE_SME, CPUID_EAX, 0, 0x8000001f, 0 }, { X86_FEATURE_SEV, CPUID_EAX, 1, 0x8000001f, 0 }, + { X86_FEATURE_SEV_ES, CPUID_EAX, 3, 0x8000001f, 0 }, { 0, 0, 0, 0, 0 } }; From patchwork Tue Jul 14 12:08:07 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662671 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 149D913B4 for ; Tue, 14 Jul 2020 12:18:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0431F22370 for ; Tue, 14 Jul 2020 12:18:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728265AbgGNMSH (ORCPT ); Tue, 14 Jul 2020 08:18:07 -0400 Received: from 8bytes.org ([81.169.241.247]:52864 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728066AbgGNMKi (ORCPT ); Tue, 14 Jul 2020 08:10:38 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id DB40A346; Tue, 14 Jul 2020 14:10:35 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 05/75] x86/traps: Move pf error codes to Date: Tue, 14 Jul 2020 14:08:07 +0200 Message-Id: <20200714120917.11253-6-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Move the definition of the x86 page-fault error code bits to the new header file asm/trap_pf.h. This makes it easier to include them into pre-decompression boot code. No functional changes. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/trap_pf.h | 24 ++++++++++++++++++++++++ arch/x86/include/asm/traps.h | 19 +------------------ 2 files changed, 25 insertions(+), 18 deletions(-) create mode 100644 arch/x86/include/asm/trap_pf.h diff --git a/arch/x86/include/asm/trap_pf.h b/arch/x86/include/asm/trap_pf.h new file mode 100644 index 000000000000..305bc1214aef --- /dev/null +++ b/arch/x86/include/asm/trap_pf.h @@ -0,0 +1,24 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_X86_TRAP_PF_H +#define _ASM_X86_TRAP_PF_H + +/* + * Page fault error code bits: + * + * bit 0 == 0: no page found 1: protection fault + * bit 1 == 0: read access 1: write access + * bit 2 == 0: kernel-mode access 1: user-mode access + * bit 3 == 1: use of reserved bit detected + * bit 4 == 1: fault was an instruction fetch + * bit 5 == 1: protection keys block access + */ +enum x86_pf_error_code { + X86_PF_PROT = 1 << 0, + X86_PF_WRITE = 1 << 1, + X86_PF_USER = 1 << 2, + X86_PF_RSVD = 1 << 3, + X86_PF_INSTR = 1 << 4, + X86_PF_PK = 1 << 5, +}; + +#endif /* _ASM_X86_TRAP_PF_H */ diff --git a/arch/x86/include/asm/traps.h b/arch/x86/include/asm/traps.h index 714b1a30e7b0..6a308355ea29 100644 --- a/arch/x86/include/asm/traps.h +++ b/arch/x86/include/asm/traps.h @@ -8,6 +8,7 @@ #include #include #include /* TRAP_TRACE, ... */ +#include #ifdef CONFIG_X86_64 asmlinkage __visible notrace struct pt_regs *sync_regs(struct pt_regs *eregs); @@ -41,22 +42,4 @@ void __noreturn handle_stack_overflow(const char *message, unsigned long fault_address); #endif -/* - * Page fault error code bits: - * - * bit 0 == 0: no page found 1: protection fault - * bit 1 == 0: read access 1: write access - * bit 2 == 0: kernel-mode access 1: user-mode access - * bit 3 == 1: use of reserved bit detected - * bit 4 == 1: fault was an instruction fetch - * bit 5 == 1: protection keys block access - */ -enum x86_pf_error_code { - X86_PF_PROT = 1 << 0, - X86_PF_WRITE = 1 << 1, - X86_PF_USER = 1 << 2, - X86_PF_RSVD = 1 << 3, - X86_PF_INSTR = 1 << 4, - X86_PF_PK = 1 << 5, -}; #endif /* _ASM_X86_TRAPS_H */ From patchwork Tue Jul 14 12:08:08 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662663 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 2A5B113A4 for ; Tue, 14 Jul 2020 12:17:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1ADC4217A0 for ; Tue, 14 Jul 2020 12:17:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728634AbgGNMRy (ORCPT ); Tue, 14 Jul 2020 08:17:54 -0400 Received: from 8bytes.org ([81.169.241.247]:52886 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728117AbgGNMKi (ORCPT ); Tue, 14 Jul 2020 08:10:38 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 64F7036B; Tue, 14 Jul 2020 14:10:36 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 06/75] x86/insn: Make inat-tables.c suitable for pre-decompression code Date: Tue, 14 Jul 2020 14:08:08 +0200 Message-Id: <20200714120917.11253-7-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel The inat-tables.c file has some arrays in it that contain pointers to other arrays. These pointers need to be relocated when the kernel image is moved to a different location. The pre-decompression boot-code has no support for applying ELF relocations, so initialize these arrays at runtime in the pre-decompression code to make sure all pointers are correctly initialized. Signed-off-by: Joerg Roedel Acked-by: Masami Hiramatsu --- arch/x86/tools/gen-insn-attr-x86.awk | 50 +++++++++++++++++++++- tools/arch/x86/tools/gen-insn-attr-x86.awk | 50 +++++++++++++++++++++- 2 files changed, 98 insertions(+), 2 deletions(-) diff --git a/arch/x86/tools/gen-insn-attr-x86.awk b/arch/x86/tools/gen-insn-attr-x86.awk index a42015b305f4..af38469afd14 100644 --- a/arch/x86/tools/gen-insn-attr-x86.awk +++ b/arch/x86/tools/gen-insn-attr-x86.awk @@ -362,6 +362,9 @@ function convert_operands(count,opnd, i,j,imm,mod) END { if (awkchecked != "") exit 1 + + print "#ifndef __BOOT_COMPRESSED\n" + # print escape opcode map's array print "/* Escape opcode map array */" print "const insn_attr_t * const inat_escape_tables[INAT_ESC_MAX + 1]" \ @@ -388,6 +391,51 @@ END { for (j = 0; j < max_lprefix; j++) if (atable[i,j]) print " ["i"]["j"] = "atable[i,j]"," - print "};" + print "};\n" + + print "#else /* !__BOOT_COMPRESSED */\n" + + print "/* Escape opcode map array */" + print "static const insn_attr_t *inat_escape_tables[INAT_ESC_MAX + 1]" \ + "[INAT_LSTPFX_MAX + 1];" + print "" + + print "/* Group opcode map array */" + print "static const insn_attr_t *inat_group_tables[INAT_GRP_MAX + 1]"\ + "[INAT_LSTPFX_MAX + 1];" + print "" + + print "/* AVX opcode map array */" + print "static const insn_attr_t *inat_avx_tables[X86_VEX_M_MAX + 1]"\ + "[INAT_LSTPFX_MAX + 1];" + print "" + + print "static void inat_init_tables(void)" + print "{" + + # print escape opcode map's array + print "\t/* Print Escape opcode map array */" + for (i = 0; i < geid; i++) + for (j = 0; j < max_lprefix; j++) + if (etable[i,j]) + print "\tinat_escape_tables["i"]["j"] = "etable[i,j]";" + print "" + + # print group opcode map's array + print "\t/* Print Group opcode map array */" + for (i = 0; i < ggid; i++) + for (j = 0; j < max_lprefix; j++) + if (gtable[i,j]) + print "\tinat_group_tables["i"]["j"] = "gtable[i,j]";" + print "" + # print AVX opcode map's array + print "\t/* Print AVX opcode map array */" + for (i = 0; i < gaid; i++) + for (j = 0; j < max_lprefix; j++) + if (atable[i,j]) + print "\tinat_avx_tables["i"]["j"] = "atable[i,j]";" + + print "}" + print "#endif" } diff --git a/tools/arch/x86/tools/gen-insn-attr-x86.awk b/tools/arch/x86/tools/gen-insn-attr-x86.awk index a42015b305f4..af38469afd14 100644 --- a/tools/arch/x86/tools/gen-insn-attr-x86.awk +++ b/tools/arch/x86/tools/gen-insn-attr-x86.awk @@ -362,6 +362,9 @@ function convert_operands(count,opnd, i,j,imm,mod) END { if (awkchecked != "") exit 1 + + print "#ifndef __BOOT_COMPRESSED\n" + # print escape opcode map's array print "/* Escape opcode map array */" print "const insn_attr_t * const inat_escape_tables[INAT_ESC_MAX + 1]" \ @@ -388,6 +391,51 @@ END { for (j = 0; j < max_lprefix; j++) if (atable[i,j]) print " ["i"]["j"] = "atable[i,j]"," - print "};" + print "};\n" + + print "#else /* !__BOOT_COMPRESSED */\n" + + print "/* Escape opcode map array */" + print "static const insn_attr_t *inat_escape_tables[INAT_ESC_MAX + 1]" \ + "[INAT_LSTPFX_MAX + 1];" + print "" + + print "/* Group opcode map array */" + print "static const insn_attr_t *inat_group_tables[INAT_GRP_MAX + 1]"\ + "[INAT_LSTPFX_MAX + 1];" + print "" + + print "/* AVX opcode map array */" + print "static const insn_attr_t *inat_avx_tables[X86_VEX_M_MAX + 1]"\ + "[INAT_LSTPFX_MAX + 1];" + print "" + + print "static void inat_init_tables(void)" + print "{" + + # print escape opcode map's array + print "\t/* Print Escape opcode map array */" + for (i = 0; i < geid; i++) + for (j = 0; j < max_lprefix; j++) + if (etable[i,j]) + print "\tinat_escape_tables["i"]["j"] = "etable[i,j]";" + print "" + + # print group opcode map's array + print "\t/* Print Group opcode map array */" + for (i = 0; i < ggid; i++) + for (j = 0; j < max_lprefix; j++) + if (gtable[i,j]) + print "\tinat_group_tables["i"]["j"] = "gtable[i,j]";" + print "" + # print AVX opcode map's array + print "\t/* Print AVX opcode map array */" + for (i = 0; i < gaid; i++) + for (j = 0; j < max_lprefix; j++) + if (atable[i,j]) + print "\tinat_avx_tables["i"]["j"] = "atable[i,j]";" + + print "}" + print "#endif" } From patchwork Tue Jul 14 12:08:09 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662661 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A0AB113B4 for ; Tue, 14 Jul 2020 12:17:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 926302068F for ; Tue, 14 Jul 2020 12:17:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728867AbgGNMRt (ORCPT ); Tue, 14 Jul 2020 08:17:49 -0400 Received: from 8bytes.org ([81.169.241.247]:52918 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726889AbgGNMKj (ORCPT ); Tue, 14 Jul 2020 08:10:39 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id DBD6B477; Tue, 14 Jul 2020 14:10:36 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 07/75] x86/umip: Factor out instruction fetch Date: Tue, 14 Jul 2020 14:08:09 +0200 Message-Id: <20200714120917.11253-8-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Factor out the code to fetch the instruction from user-space to a helper function. No functional changes. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/insn-eval.h | 2 ++ arch/x86/kernel/umip.c | 26 +++++----------------- arch/x86/lib/insn-eval.c | 38 ++++++++++++++++++++++++++++++++ 3 files changed, 46 insertions(+), 20 deletions(-) diff --git a/arch/x86/include/asm/insn-eval.h b/arch/x86/include/asm/insn-eval.h index 2b6ccf2c49f1..b8b9ef1bbd06 100644 --- a/arch/x86/include/asm/insn-eval.h +++ b/arch/x86/include/asm/insn-eval.h @@ -19,5 +19,7 @@ void __user *insn_get_addr_ref(struct insn *insn, struct pt_regs *regs); int insn_get_modrm_rm_off(struct insn *insn, struct pt_regs *regs); unsigned long insn_get_seg_base(struct pt_regs *regs, int seg_reg_idx); int insn_get_code_seg_params(struct pt_regs *regs); +int insn_fetch_from_user(struct pt_regs *regs, + unsigned char buf[MAX_INSN_SIZE]); #endif /* _ASM_X86_INSN_EVAL_H */ diff --git a/arch/x86/kernel/umip.c b/arch/x86/kernel/umip.c index 8d5cbe1bbb3b..c9e5345da793 100644 --- a/arch/x86/kernel/umip.c +++ b/arch/x86/kernel/umip.c @@ -317,11 +317,11 @@ static void force_sig_info_umip_fault(void __user *addr, struct pt_regs *regs) */ bool fixup_umip_exception(struct pt_regs *regs) { - int not_copied, nr_copied, reg_offset, dummy_data_size, umip_inst; - unsigned long seg_base = 0, *reg_addr; + int nr_copied, reg_offset, dummy_data_size, umip_inst; /* 10 bytes is the maximum size of the result of UMIP instructions */ unsigned char dummy_data[10] = { 0 }; unsigned char buf[MAX_INSN_SIZE]; + unsigned long *reg_addr; void __user *uaddr; struct insn insn; int seg_defs; @@ -329,26 +329,12 @@ bool fixup_umip_exception(struct pt_regs *regs) if (!regs) return false; - /* - * If not in user-space long mode, a custom code segment could be in - * use. This is true in protected mode (if the process defined a local - * descriptor table), or virtual-8086 mode. In most of the cases - * seg_base will be zero as in USER_CS. - */ - if (!user_64bit_mode(regs)) - seg_base = insn_get_seg_base(regs, INAT_SEG_REG_CS); - - if (seg_base == -1L) - return false; - - not_copied = copy_from_user(buf, (void __user *)(seg_base + regs->ip), - sizeof(buf)); - nr_copied = sizeof(buf) - not_copied; + nr_copied = insn_fetch_from_user(regs, buf); /* - * The copy_from_user above could have failed if user code is protected - * by a memory protection key. Give up on emulation in such a case. - * Should we issue a page fault? + * The insn_fetch_from_user above could have failed if user code + * is protected by a memory protection key. Give up on emulation + * in such a case. Should we issue a page fault? */ if (!nr_copied) return false; diff --git a/arch/x86/lib/insn-eval.c b/arch/x86/lib/insn-eval.c index 31600d851fd8..0c4f7ebc261b 100644 --- a/arch/x86/lib/insn-eval.c +++ b/arch/x86/lib/insn-eval.c @@ -1369,3 +1369,41 @@ void __user *insn_get_addr_ref(struct insn *insn, struct pt_regs *regs) return (void __user *)-1L; } } + +/** + * insn_fetch_from_user() - Copy instruction bytes from user-space memory + * @regs: Structure with register values as seen when entering kernel mode + * @buf: Array to store the fetched instruction + * + * Gets the linear address of the instruction and copies the instruction bytes + * to the buf. + * + * Returns: + * + * Number of instruction bytes copied. + * + * 0 if nothing was copied. + */ +int insn_fetch_from_user(struct pt_regs *regs, unsigned char buf[MAX_INSN_SIZE]) +{ + unsigned long seg_base = 0; + int not_copied; + + /* + * If not in user-space long mode, a custom code segment could be in + * use. This is true in protected mode (if the process defined a local + * descriptor table), or virtual-8086 mode. In most of the cases + * seg_base will be zero as in USER_CS. + */ + if (!user_64bit_mode(regs)) { + seg_base = insn_get_seg_base(regs, INAT_SEG_REG_CS); + if (seg_base == -1L) + return 0; + } + + + not_copied = copy_from_user(buf, (void __user *)(seg_base + regs->ip), + MAX_INSN_SIZE); + + return MAX_INSN_SIZE - not_copied; +} From patchwork Tue Jul 14 12:08:10 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662527 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 9AFDA618 for ; Tue, 14 Jul 2020 12:10:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8BD4E22227 for ; Tue, 14 Jul 2020 12:10:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728210AbgGNMKl (ORCPT ); Tue, 14 Jul 2020 08:10:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60608 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728177AbgGNMKk (ORCPT ); Tue, 14 Jul 2020 08:10:40 -0400 Received: from theia.8bytes.org (8bytes.org [IPv6:2a01:238:4383:600:38bc:a715:4b6d:a889]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0B762C061755; Tue, 14 Jul 2020 05:10:40 -0700 (PDT) Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 603BD4C4; Tue, 14 Jul 2020 14:10:37 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 08/75] x86/umip: Factor out instruction decoding Date: Tue, 14 Jul 2020 14:08:10 +0200 Message-Id: <20200714120917.11253-9-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Factor out the code used to decode an instruction with the correct address and operand sizes to a helper function. No functional changes. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/insn-eval.h | 2 ++ arch/x86/kernel/umip.c | 23 +--------------- arch/x86/lib/insn-eval.c | 45 ++++++++++++++++++++++++++++++++ 3 files changed, 48 insertions(+), 22 deletions(-) diff --git a/arch/x86/include/asm/insn-eval.h b/arch/x86/include/asm/insn-eval.h index b8b9ef1bbd06..392b4fe377f9 100644 --- a/arch/x86/include/asm/insn-eval.h +++ b/arch/x86/include/asm/insn-eval.h @@ -21,5 +21,7 @@ unsigned long insn_get_seg_base(struct pt_regs *regs, int seg_reg_idx); int insn_get_code_seg_params(struct pt_regs *regs); int insn_fetch_from_user(struct pt_regs *regs, unsigned char buf[MAX_INSN_SIZE]); +bool insn_decode(struct insn *insn, struct pt_regs *regs, + unsigned char buf[MAX_INSN_SIZE], int buf_size); #endif /* _ASM_X86_INSN_EVAL_H */ diff --git a/arch/x86/kernel/umip.c b/arch/x86/kernel/umip.c index c9e5345da793..4d9044340e78 100644 --- a/arch/x86/kernel/umip.c +++ b/arch/x86/kernel/umip.c @@ -324,7 +324,6 @@ bool fixup_umip_exception(struct pt_regs *regs) unsigned long *reg_addr; void __user *uaddr; struct insn insn; - int seg_defs; if (!regs) return false; @@ -339,27 +338,7 @@ bool fixup_umip_exception(struct pt_regs *regs) if (!nr_copied) return false; - insn_init(&insn, buf, nr_copied, user_64bit_mode(regs)); - - /* - * Override the default operand and address sizes with what is specified - * in the code segment descriptor. The instruction decoder only sets - * the address size it to either 4 or 8 address bytes and does nothing - * for the operand bytes. This OK for most of the cases, but we could - * have special cases where, for instance, a 16-bit code segment - * descriptor is used. - * If there is an address override prefix, the instruction decoder - * correctly updates these values, even for 16-bit defaults. - */ - seg_defs = insn_get_code_seg_params(regs); - if (seg_defs == -EINVAL) - return false; - - insn.addr_bytes = INSN_CODE_SEG_ADDR_SZ(seg_defs); - insn.opnd_bytes = INSN_CODE_SEG_OPND_SZ(seg_defs); - - insn_get_length(&insn); - if (nr_copied < insn.length) + if (!insn_decode(&insn, regs, buf, nr_copied)) return false; umip_inst = identify_insn(&insn); diff --git a/arch/x86/lib/insn-eval.c b/arch/x86/lib/insn-eval.c index 0c4f7ebc261b..f52046f90dd3 100644 --- a/arch/x86/lib/insn-eval.c +++ b/arch/x86/lib/insn-eval.c @@ -1407,3 +1407,48 @@ int insn_fetch_from_user(struct pt_regs *regs, unsigned char buf[MAX_INSN_SIZE]) return MAX_INSN_SIZE - not_copied; } + +/** + * insn_decode() - Decode an instruction + * @insn: Structure to store decoded instruction + * @regs: Structure with register values as seen when entering kernel mode + * @buf: Buffer containing the instruction bytes + * @buf_size: Number of instruction bytes available in buf + * + * Decodes the instruction provided in buf and stores the decoding results in + * insn. Also determines the correct address and operand sizes. + * + * Returns: + * + * True if instruction was decoded, False otherwise. + */ +bool insn_decode(struct insn *insn, struct pt_regs *regs, + unsigned char buf[MAX_INSN_SIZE], int buf_size) +{ + int seg_defs; + + insn_init(insn, buf, buf_size, user_64bit_mode(regs)); + + /* + * Override the default operand and address sizes with what is specified + * in the code segment descriptor. The instruction decoder only sets + * the address size it to either 4 or 8 address bytes and does nothing + * for the operand bytes. This OK for most of the cases, but we could + * have special cases where, for instance, a 16-bit code segment + * descriptor is used. + * If there is an address override prefix, the instruction decoder + * correctly updates these values, even for 16-bit defaults. + */ + seg_defs = insn_get_code_seg_params(regs); + if (seg_defs == -EINVAL) + return false; + + insn->addr_bytes = INSN_CODE_SEG_ADDR_SZ(seg_defs); + insn->opnd_bytes = INSN_CODE_SEG_OPND_SZ(seg_defs); + + insn_get_length(insn); + if (buf_size < insn->length) + return false; + + return true; +} From patchwork Tue Jul 14 12:08:11 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662525 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 623C113B4 for ; Tue, 14 Jul 2020 12:10:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5159422240 for ; Tue, 14 Jul 2020 12:10:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728196AbgGNMKk (ORCPT ); Tue, 14 Jul 2020 08:10:40 -0400 Received: from 8bytes.org ([81.169.241.247]:52864 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728168AbgGNMKj (ORCPT ); Tue, 14 Jul 2020 08:10:39 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id E052E4CA; Tue, 14 Jul 2020 14:10:37 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , Masami Hiramatsu , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 09/75] x86/insn: Add insn_get_modrm_reg_off() Date: Tue, 14 Jul 2020 14:08:11 +0200 Message-Id: <20200714120917.11253-10-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Add a function to the instruction decoder which returns the pt_regs offset of the register specified in the reg field of the modrm byte. Signed-off-by: Joerg Roedel Acked-by: Masami Hiramatsu --- arch/x86/include/asm/insn-eval.h | 1 + arch/x86/lib/insn-eval.c | 23 +++++++++++++++++++++++ 2 files changed, 24 insertions(+) diff --git a/arch/x86/include/asm/insn-eval.h b/arch/x86/include/asm/insn-eval.h index 392b4fe377f9..f748f57f1491 100644 --- a/arch/x86/include/asm/insn-eval.h +++ b/arch/x86/include/asm/insn-eval.h @@ -17,6 +17,7 @@ void __user *insn_get_addr_ref(struct insn *insn, struct pt_regs *regs); int insn_get_modrm_rm_off(struct insn *insn, struct pt_regs *regs); +int insn_get_modrm_reg_off(struct insn *insn, struct pt_regs *regs); unsigned long insn_get_seg_base(struct pt_regs *regs, int seg_reg_idx); int insn_get_code_seg_params(struct pt_regs *regs); int insn_fetch_from_user(struct pt_regs *regs, diff --git a/arch/x86/lib/insn-eval.c b/arch/x86/lib/insn-eval.c index f52046f90dd3..a8ac5c5e94f0 100644 --- a/arch/x86/lib/insn-eval.c +++ b/arch/x86/lib/insn-eval.c @@ -20,6 +20,7 @@ enum reg_type { REG_TYPE_RM = 0, + REG_TYPE_REG, REG_TYPE_INDEX, REG_TYPE_BASE, }; @@ -441,6 +442,13 @@ static int get_reg_offset(struct insn *insn, struct pt_regs *regs, regno += 8; break; + case REG_TYPE_REG: + regno = X86_MODRM_REG(insn->modrm.value); + + if (X86_REX_R(insn->rex_prefix.value)) + regno += 8; + break; + case REG_TYPE_INDEX: regno = X86_SIB_INDEX(insn->sib.value); if (X86_REX_X(insn->rex_prefix.value)) @@ -809,6 +817,21 @@ int insn_get_modrm_rm_off(struct insn *insn, struct pt_regs *regs) return get_reg_offset(insn, regs, REG_TYPE_RM); } +/** + * insn_get_modrm_reg_off() - Obtain register in reg part of the ModRM byte + * @insn: Instruction containing the ModRM byte + * @regs: Register values as seen when entering kernel mode + * + * Returns: + * + * The register indicated by the reg part of the ModRM byte. The + * register is obtained as an offset from the base of pt_regs. + */ +int insn_get_modrm_reg_off(struct insn *insn, struct pt_regs *regs) +{ + return get_reg_offset(insn, regs, REG_TYPE_REG); +} + /** * get_seg_base_limit() - obtain base address and limit of a segment * @insn: Instruction. Must be valid. From patchwork Tue Jul 14 12:08:12 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662657 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 13B6C13A4 for ; Tue, 14 Jul 2020 12:17:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EFA3C217A0 for ; Tue, 14 Jul 2020 12:17:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728700AbgGNMRc (ORCPT ); Tue, 14 Jul 2020 08:17:32 -0400 Received: from 8bytes.org ([81.169.241.247]:52886 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728172AbgGNMKk (ORCPT ); Tue, 14 Jul 2020 08:10:40 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 6248250C; Tue, 14 Jul 2020 14:10:38 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 10/75] x86/insn: Add insn_has_rep_prefix() helper Date: Tue, 14 Jul 2020 14:08:12 +0200 Message-Id: <20200714120917.11253-11-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Add a function to check whether an instruction has a REP prefix. Signed-off-by: Joerg Roedel Reviewed-by: Masami Hiramatsu --- arch/x86/include/asm/insn-eval.h | 1 + arch/x86/lib/insn-eval.c | 24 ++++++++++++++++++++++++ 2 files changed, 25 insertions(+) diff --git a/arch/x86/include/asm/insn-eval.h b/arch/x86/include/asm/insn-eval.h index f748f57f1491..a0f839aa144d 100644 --- a/arch/x86/include/asm/insn-eval.h +++ b/arch/x86/include/asm/insn-eval.h @@ -15,6 +15,7 @@ #define INSN_CODE_SEG_OPND_SZ(params) (params & 0xf) #define INSN_CODE_SEG_PARAMS(oper_sz, addr_sz) (oper_sz | (addr_sz << 4)) +bool insn_has_rep_prefix(struct insn *insn); void __user *insn_get_addr_ref(struct insn *insn, struct pt_regs *regs); int insn_get_modrm_rm_off(struct insn *insn, struct pt_regs *regs); int insn_get_modrm_reg_off(struct insn *insn, struct pt_regs *regs); diff --git a/arch/x86/lib/insn-eval.c b/arch/x86/lib/insn-eval.c index a8ac5c5e94f0..8ed9d645259c 100644 --- a/arch/x86/lib/insn-eval.c +++ b/arch/x86/lib/insn-eval.c @@ -53,6 +53,30 @@ static bool is_string_insn(struct insn *insn) } } +/** + * insn_has_rep_prefix() - Determine if instruction has a REP prefix + * @insn: Instruction containing the prefix to inspect + * + * Returns: + * + * true if the instruction has a REP prefix, false if not. + */ +bool insn_has_rep_prefix(struct insn *insn) +{ + int i; + + insn_get_prefixes(insn); + + for (i = 0; i < insn->prefixes.nbytes; i++) { + insn_byte_t p = insn->prefixes.bytes[i]; + + if (p == 0xf2 || p == 0xf3) + return true; + } + + return false; +} + /** * get_seg_reg_override_idx() - obtain segment register override index * @insn: Valid instruction with segment override prefixes From patchwork Tue Jul 14 12:08:13 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662659 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 766B313B4 for ; Tue, 14 Jul 2020 12:17:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 67650217A0 for ; Tue, 14 Jul 2020 12:17:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728321AbgGNMRk (ORCPT ); Tue, 14 Jul 2020 08:17:40 -0400 Received: from 8bytes.org ([81.169.241.247]:52918 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726630AbgGNMKk (ORCPT ); Tue, 14 Jul 2020 08:10:40 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id DEC3E5D1; Tue, 14 Jul 2020 14:10:38 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 11/75] x86/boot/compressed/64: Disable red-zone usage Date: Tue, 14 Jul 2020 14:08:13 +0200 Message-Id: <20200714120917.11253-12-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel The x86-64 ABI defines a red-zone on the stack: The 128-byte area beyond the location pointed to by %rsp is considered to be reserved and shall not be modified by signal or interrupt handlers. Therefore, functions may use this area for temporary data that is not needed across function calls. In particular, leaf functions may use this area for their entire stack frame, rather than adjusting the stack pointer in the prologue and epilogue. This area is known as the red zone. This is not compatible with exception handling, because the IRET frame written by the hardware at the stack pointer and the functions to handle the exception will overwrite the temporary variables of the interrupted function, causing undefined behavior. So disable red-zones for the pre-decompression boot code. Signed-off-by: Joerg Roedel --- arch/x86/boot/Makefile | 2 +- arch/x86/boot/compressed/Makefile | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/boot/Makefile b/arch/x86/boot/Makefile index fe605205b4ce..4d6a16a47e9f 100644 --- a/arch/x86/boot/Makefile +++ b/arch/x86/boot/Makefile @@ -66,7 +66,7 @@ targets += cpustr.h # --------------------------------------------------------------------------- -KBUILD_CFLAGS := $(REALMODE_CFLAGS) -D_SETUP +KBUILD_CFLAGS := $(REALMODE_CFLAGS) -D_SETUP -mno-red-zone KBUILD_AFLAGS := $(KBUILD_CFLAGS) -D__ASSEMBLY__ KBUILD_CFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=) KBUILD_CFLAGS += -fno-asynchronous-unwind-tables diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile index 7619742f91c9..95ac85b8ef27 100644 --- a/arch/x86/boot/compressed/Makefile +++ b/arch/x86/boot/compressed/Makefile @@ -32,7 +32,7 @@ KBUILD_CFLAGS := -m$(BITS) -O2 KBUILD_CFLAGS += -fno-strict-aliasing $(call cc-option, -fPIE, -fPIC) KBUILD_CFLAGS += -DDISABLE_BRANCH_PROFILING cflags-$(CONFIG_X86_32) := -march=i386 -cflags-$(CONFIG_X86_64) := -mcmodel=small +cflags-$(CONFIG_X86_64) := -mcmodel=small -mno-red-zone KBUILD_CFLAGS += $(cflags-y) KBUILD_CFLAGS += -mno-mmx -mno-sse KBUILD_CFLAGS += $(call cc-option,-ffreestanding) From patchwork Tue Jul 14 12:08:14 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662651 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 7A81113A4 for ; Tue, 14 Jul 2020 12:17:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 68406217A0 for ; Tue, 14 Jul 2020 12:17:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728224AbgGNMRM (ORCPT ); Tue, 14 Jul 2020 08:17:12 -0400 Received: from 8bytes.org ([81.169.241.247]:52864 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728199AbgGNMKm (ORCPT ); Tue, 14 Jul 2020 08:10:42 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 737065DF; Tue, 14 Jul 2020 14:10:39 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 12/75] x86/boot/compressed/64: Add IDT Infrastructure Date: Tue, 14 Jul 2020 14:08:14 +0200 Message-Id: <20200714120917.11253-13-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Add code needed to setup an IDT in the early pre-decompression boot-code. The IDT is loaded first in startup_64, which is after EfiExitBootServices() has been called, and later reloaded when the kernel image has been relocated to the end of the decompression area. This allows to setup different IDT handlers before and after the relocation. Signed-off-by: Joerg Roedel --- arch/x86/boot/compressed/Makefile | 1 + arch/x86/boot/compressed/head_64.S | 25 +++++++- arch/x86/boot/compressed/idt_64.c | 44 ++++++++++++++ arch/x86/boot/compressed/idt_handlers_64.S | 70 ++++++++++++++++++++++ arch/x86/boot/compressed/misc.h | 5 ++ arch/x86/include/asm/desc_defs.h | 3 + 6 files changed, 147 insertions(+), 1 deletion(-) create mode 100644 arch/x86/boot/compressed/idt_64.c create mode 100644 arch/x86/boot/compressed/idt_handlers_64.S diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile index 95ac85b8ef27..46928cb90d19 100644 --- a/arch/x86/boot/compressed/Makefile +++ b/arch/x86/boot/compressed/Makefile @@ -84,6 +84,7 @@ vmlinux-objs-$(CONFIG_EARLY_PRINTK) += $(obj)/early_serial_console.o vmlinux-objs-$(CONFIG_RANDOMIZE_BASE) += $(obj)/kaslr.o ifdef CONFIG_X86_64 vmlinux-objs-$(CONFIG_RANDOMIZE_BASE) += $(obj)/kaslr_64.o + vmlinux-objs-y += $(obj)/idt_64.o $(obj)/idt_handlers_64.o vmlinux-objs-y += $(obj)/mem_encrypt.o vmlinux-objs-y += $(obj)/pgtable_64.o endif diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S index 97d37f0a34f5..4174d2f97b29 100644 --- a/arch/x86/boot/compressed/head_64.S +++ b/arch/x86/boot/compressed/head_64.S @@ -33,6 +33,7 @@ #include #include #include +#include #include "pgtable.h" /* @@ -410,6 +411,10 @@ SYM_CODE_START(startup_64) .Lon_kernel_cs: + pushq %rsi + call load_stage1_idt + popq %rsi + /* * paging_prepare() sets up the trampoline and checks if we need to * enable 5-level paging. @@ -537,6 +542,13 @@ SYM_FUNC_START_LOCAL_NOALIGN(.Lrelocated) shrq $3, %rcx rep stosq +/* + * Load stage2 IDT + */ + pushq %rsi + call load_stage2_idt + popq %rsi + /* * Do the extraction, and jump to the new kernel.. */ @@ -690,10 +702,21 @@ SYM_DATA_START_LOCAL(gdt) .quad 0x0000000000000000 /* TS continued */ SYM_DATA_END_LABEL(gdt, SYM_L_LOCAL, gdt_end) +SYM_DATA_START(boot_idt_desc) + .word boot_idt_end - boot_idt + .quad 0 +SYM_DATA_END(boot_idt_desc) + .balign 8 +SYM_DATA_START(boot_idt) + .rept BOOT_IDT_ENTRIES + .quad 0 + .quad 0 + .endr +SYM_DATA_END_LABEL(boot_idt, SYM_L_GLOBAL, boot_idt_end) + #ifdef CONFIG_EFI_STUB SYM_DATA(image_offset, .long 0) #endif - #ifdef CONFIG_EFI_MIXED SYM_DATA_LOCAL(efi32_boot_args, .long 0, 0, 0) SYM_DATA(efi_is64, .byte 1) diff --git a/arch/x86/boot/compressed/idt_64.c b/arch/x86/boot/compressed/idt_64.c new file mode 100644 index 000000000000..082cd6bca033 --- /dev/null +++ b/arch/x86/boot/compressed/idt_64.c @@ -0,0 +1,44 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include +#include +#include +#include "misc.h" + +static void set_idt_entry(int vector, void (*handler)(void)) +{ + unsigned long address = (unsigned long)handler; + gate_desc entry; + + memset(&entry, 0, sizeof(entry)); + + entry.offset_low = (u16)(address & 0xffff); + entry.segment = __KERNEL_CS; + entry.bits.type = GATE_TRAP; + entry.bits.p = 1; + entry.offset_middle = (u16)((address >> 16) & 0xffff); + entry.offset_high = (u32)(address >> 32); + + memcpy(&boot_idt[vector], &entry, sizeof(entry)); +} + +/* Have this here so we don't need to include */ +static void load_boot_idt(const struct desc_ptr *dtr) +{ + asm volatile("lidt %0"::"m" (*dtr)); +} + +/* Setup IDT before kernel jumping to .Lrelocated */ +void load_stage1_idt(void) +{ + boot_idt_desc.address = (unsigned long)boot_idt; + + load_boot_idt(&boot_idt_desc); +} + +/* Setup IDT after kernel jumping to .Lrelocated */ +void load_stage2_idt(void) +{ + boot_idt_desc.address = (unsigned long)boot_idt; + + load_boot_idt(&boot_idt_desc); +} diff --git a/arch/x86/boot/compressed/idt_handlers_64.S b/arch/x86/boot/compressed/idt_handlers_64.S new file mode 100644 index 000000000000..36dee2f40a8b --- /dev/null +++ b/arch/x86/boot/compressed/idt_handlers_64.S @@ -0,0 +1,70 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Early IDT handler entry points + * + * Copyright (C) 2019 SUSE + * + * Author: Joerg Roedel + */ + +#include + +/* For ORIG_RAX */ +#include "../../entry/calling.h" + +.macro EXCEPTION_HANDLER name function error_code=0 +SYM_FUNC_START(\name) + + /* Build pt_regs */ + .if \error_code == 0 + pushq $0 + .endif + + pushq %rdi + pushq %rsi + pushq %rdx + pushq %rcx + pushq %rax + pushq %r8 + pushq %r9 + pushq %r10 + pushq %r11 + pushq %rbx + pushq %rbp + pushq %r12 + pushq %r13 + pushq %r14 + pushq %r15 + + /* Call handler with pt_regs */ + movq %rsp, %rdi + /* Error code is second parameter */ + movq ORIG_RAX(%rsp), %rsi + call \function + + /* Restore regs */ + popq %r15 + popq %r14 + popq %r13 + popq %r12 + popq %rbp + popq %rbx + popq %r11 + popq %r10 + popq %r9 + popq %r8 + popq %rax + popq %rcx + popq %rdx + popq %rsi + popq %rdi + + /* Remove error code and return */ + addq $8, %rsp + + iretq +SYM_FUNC_END(\name) + .endm + + .text + .code64 diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h index 726e264410ff..062ae3ae6930 100644 --- a/arch/x86/boot/compressed/misc.h +++ b/arch/x86/boot/compressed/misc.h @@ -23,6 +23,7 @@ #include #include #include +#include #define BOOT_CTYPE_H #include @@ -133,4 +134,8 @@ int count_immovable_mem_regions(void); static inline int count_immovable_mem_regions(void) { return 0; } #endif +/* idt_64.c */ +extern gate_desc boot_idt[BOOT_IDT_ENTRIES]; +extern struct desc_ptr boot_idt_desc; + #endif /* BOOT_COMPRESSED_MISC_H */ diff --git a/arch/x86/include/asm/desc_defs.h b/arch/x86/include/asm/desc_defs.h index a91f3b6e4f2a..5621fb3f2d1a 100644 --- a/arch/x86/include/asm/desc_defs.h +++ b/arch/x86/include/asm/desc_defs.h @@ -109,6 +109,9 @@ struct desc_ptr { #endif /* !__ASSEMBLY__ */ +/* Boot IDT definitions */ +#define BOOT_IDT_ENTRIES 32 + /* Access rights as returned by LAR */ #define AR_TYPE_RODATA (0 * (1 << 9)) #define AR_TYPE_RWDATA (1 * (1 << 9)) From patchwork Tue Jul 14 12:08:15 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662645 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id CC85113A4 for ; Tue, 14 Jul 2020 12:17:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BC8EB22370 for ; Tue, 14 Jul 2020 12:17:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728999AbgGNMQ5 (ORCPT ); Tue, 14 Jul 2020 08:16:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60618 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728230AbgGNMKn (ORCPT ); Tue, 14 Jul 2020 08:10:43 -0400 Received: from theia.8bytes.org (8bytes.org [IPv6:2a01:238:4383:600:38bc:a715:4b6d:a889]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EF463C061755; Tue, 14 Jul 2020 05:10:42 -0700 (PDT) Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id F394760E; Tue, 14 Jul 2020 14:10:39 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 13/75] x86/boot/compressed/64: Rename kaslr_64.c to ident_map_64.c Date: Tue, 14 Jul 2020 14:08:15 +0200 Message-Id: <20200714120917.11253-14-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel The file contains only code related to identity mapped page-tables. Rename the file and compile it always in. Signed-off-by: Joerg Roedel Reviewed-by: Kees Cook --- arch/x86/boot/compressed/Makefile | 2 +- arch/x86/boot/compressed/{kaslr_64.c => ident_map_64.c} | 9 +++++++++ arch/x86/boot/compressed/kaslr.c | 9 --------- arch/x86/boot/compressed/misc.h | 8 ++++++++ 4 files changed, 18 insertions(+), 10 deletions(-) rename arch/x86/boot/compressed/{kaslr_64.c => ident_map_64.c} (95%) diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile index 46928cb90d19..c825c95d13b9 100644 --- a/arch/x86/boot/compressed/Makefile +++ b/arch/x86/boot/compressed/Makefile @@ -83,7 +83,7 @@ vmlinux-objs-y := $(obj)/vmlinux.lds $(obj)/kernel_info.o $(obj)/head_$(BITS).o vmlinux-objs-$(CONFIG_EARLY_PRINTK) += $(obj)/early_serial_console.o vmlinux-objs-$(CONFIG_RANDOMIZE_BASE) += $(obj)/kaslr.o ifdef CONFIG_X86_64 - vmlinux-objs-$(CONFIG_RANDOMIZE_BASE) += $(obj)/kaslr_64.o + vmlinux-objs-y += $(obj)/ident_map_64.o vmlinux-objs-y += $(obj)/idt_64.o $(obj)/idt_handlers_64.o vmlinux-objs-y += $(obj)/mem_encrypt.o vmlinux-objs-y += $(obj)/pgtable_64.o diff --git a/arch/x86/boot/compressed/kaslr_64.c b/arch/x86/boot/compressed/ident_map_64.c similarity index 95% rename from arch/x86/boot/compressed/kaslr_64.c rename to arch/x86/boot/compressed/ident_map_64.c index f9c5c13d979b..d9932a133ac9 100644 --- a/arch/x86/boot/compressed/kaslr_64.c +++ b/arch/x86/boot/compressed/ident_map_64.c @@ -29,6 +29,15 @@ #define __PAGE_OFFSET __PAGE_OFFSET_BASE #include "../../mm/ident_map.c" +#ifdef CONFIG_X86_5LEVEL +unsigned int __pgtable_l5_enabled; +unsigned int pgdir_shift = 39; +unsigned int ptrs_per_p4d = 1; +#endif + +/* Used by PAGE_KERN* macros: */ +pteval_t __default_kernel_pte_mask __read_mostly = ~0; + /* Used to track our page table allocation area. */ struct alloc_pgt_data { unsigned char *pgt_buf; diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c index d7408af55738..7c61a8c5b9cf 100644 --- a/arch/x86/boot/compressed/kaslr.c +++ b/arch/x86/boot/compressed/kaslr.c @@ -43,17 +43,8 @@ #define STATIC #include -#ifdef CONFIG_X86_5LEVEL -unsigned int __pgtable_l5_enabled; -unsigned int pgdir_shift __ro_after_init = 39; -unsigned int ptrs_per_p4d __ro_after_init = 1; -#endif - extern unsigned long get_cmd_line_ptr(void); -/* Used by PAGE_KERN* macros: */ -pteval_t __default_kernel_pte_mask __read_mostly = ~0; - /* Simplified build-specific string for starting entropy. */ static const char build_str[] = UTS_RELEASE " (" LINUX_COMPILE_BY "@" LINUX_COMPILE_HOST ") (" LINUX_COMPILER ") " UTS_VERSION; diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h index 062ae3ae6930..3a030a878d53 100644 --- a/arch/x86/boot/compressed/misc.h +++ b/arch/x86/boot/compressed/misc.h @@ -134,6 +134,14 @@ int count_immovable_mem_regions(void); static inline int count_immovable_mem_regions(void) { return 0; } #endif +/* ident_map_64.c */ +#ifdef CONFIG_X86_5LEVEL +extern unsigned int __pgtable_l5_enabled, pgdir_shift, ptrs_per_p4d; +#endif + +/* Used by PAGE_KERN* macros: */ +extern pteval_t __default_kernel_pte_mask; + /* idt_64.c */ extern gate_desc boot_idt[BOOT_IDT_ENTRIES]; extern struct desc_ptr boot_idt_desc; From patchwork Tue Jul 14 12:08:16 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662653 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 6FA1513A4 for ; Tue, 14 Jul 2020 12:17:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6182D217A0 for ; Tue, 14 Jul 2020 12:17:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728747AbgGNMRM (ORCPT ); Tue, 14 Jul 2020 08:17:12 -0400 Received: from 8bytes.org ([81.169.241.247]:52918 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728214AbgGNMKm (ORCPT ); Tue, 14 Jul 2020 08:10:42 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 7C9B3638; Tue, 14 Jul 2020 14:10:40 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 14/75] x86/boot/compressed/64: Add page-fault handler Date: Tue, 14 Jul 2020 14:08:16 +0200 Message-Id: <20200714120917.11253-15-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Install a page-fault handler to add an identity mapping to addresses not yet mapped. Also do some checking whether the error code is sane. This makes non SEV-ES machines use the exception handling infrastructure in the pre-decompressions boot code too, making it less likely to break in the future. Signed-off-by: Joerg Roedel Reviewed-by: Kees Cook --- arch/x86/boot/compressed/ident_map_64.c | 39 ++++++++++++++++++++++ arch/x86/boot/compressed/idt_64.c | 2 ++ arch/x86/boot/compressed/idt_handlers_64.S | 2 ++ arch/x86/boot/compressed/misc.h | 6 ++++ 4 files changed, 49 insertions(+) diff --git a/arch/x86/boot/compressed/ident_map_64.c b/arch/x86/boot/compressed/ident_map_64.c index d9932a133ac9..e3d980ae9c2b 100644 --- a/arch/x86/boot/compressed/ident_map_64.c +++ b/arch/x86/boot/compressed/ident_map_64.c @@ -19,10 +19,13 @@ /* No PAGE_TABLE_ISOLATION support needed either: */ #undef CONFIG_PAGE_TABLE_ISOLATION +#include "error.h" #include "misc.h" /* These actually do the work of building the kernel identity maps. */ #include +#include +#include #include /* Use the static base for this part of the boot process */ #undef __PAGE_OFFSET @@ -160,3 +163,39 @@ void finalize_identity_maps(void) { write_cr3(top_level_pgt); } + +static void do_pf_error(const char *msg, unsigned long error_code, + unsigned long address, unsigned long ip) +{ + error_putstr(msg); + + error_putstr("\nError Code: "); + error_puthex(error_code); + error_putstr("\nCR2: 0x"); + error_puthex(address); + error_putstr("\nRIP relative to _head: 0x"); + error_puthex(ip - (unsigned long)_head); + error_putstr("\n"); + + error("Stopping.\n"); +} + +void do_boot_page_fault(struct pt_regs *regs, unsigned long error_code) +{ + unsigned long address = native_read_cr2(); + + /* + * Check for unexpected error codes. Unexpected are: + * - Faults on present pages + * - User faults + * - Reserved bits set + */ + if (error_code & (X86_PF_PROT | X86_PF_USER | X86_PF_RSVD)) + do_pf_error("Unexpected page-fault:", error_code, address, regs->ip); + + /* + * Error code is sane - now identity map the 2M region around + * the faulting address. + */ + add_identity_map(address & PMD_MASK, PMD_SIZE); +} diff --git a/arch/x86/boot/compressed/idt_64.c b/arch/x86/boot/compressed/idt_64.c index 082cd6bca033..5f083092a86d 100644 --- a/arch/x86/boot/compressed/idt_64.c +++ b/arch/x86/boot/compressed/idt_64.c @@ -40,5 +40,7 @@ void load_stage2_idt(void) { boot_idt_desc.address = (unsigned long)boot_idt; + set_idt_entry(X86_TRAP_PF, boot_page_fault); + load_boot_idt(&boot_idt_desc); } diff --git a/arch/x86/boot/compressed/idt_handlers_64.S b/arch/x86/boot/compressed/idt_handlers_64.S index 36dee2f40a8b..b20e57504a94 100644 --- a/arch/x86/boot/compressed/idt_handlers_64.S +++ b/arch/x86/boot/compressed/idt_handlers_64.S @@ -68,3 +68,5 @@ SYM_FUNC_END(\name) .text .code64 + +EXCEPTION_HANDLER boot_page_fault do_boot_page_fault error_code=1 diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h index 3a030a878d53..345c90fbc500 100644 --- a/arch/x86/boot/compressed/misc.h +++ b/arch/x86/boot/compressed/misc.h @@ -37,6 +37,9 @@ #define memptr unsigned #endif +/* boot/compressed/vmlinux start and end markers */ +extern char _head[], _end[]; + /* misc.c */ extern memptr free_mem_ptr; extern memptr free_mem_end_ptr; @@ -146,4 +149,7 @@ extern pteval_t __default_kernel_pte_mask; extern gate_desc boot_idt[BOOT_IDT_ENTRIES]; extern struct desc_ptr boot_idt_desc; +/* IDT Entry Points */ +void boot_page_fault(void); + #endif /* BOOT_COMPRESSED_MISC_H */ From patchwork Tue Jul 14 12:08:17 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662655 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E208D13A4 for ; Tue, 14 Jul 2020 12:17:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D54D222404 for ; Tue, 14 Jul 2020 12:17:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728186AbgGNMRL (ORCPT ); Tue, 14 Jul 2020 08:17:11 -0400 Received: from 8bytes.org ([81.169.241.247]:52886 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728224AbgGNMKn (ORCPT ); Tue, 14 Jul 2020 08:10:43 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 0628F6A7; Tue, 14 Jul 2020 14:10:41 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 15/75] x86/boot/compressed/64: Always switch to own page-table Date: Tue, 14 Jul 2020 14:08:17 +0200 Message-Id: <20200714120917.11253-16-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel When booted through startup_64 the kernel keeps running on the EFI page-table until the KASLR code sets up its own page-table. Without KASLR the pre-decompression boot code never switches off the EFI page-table. Change that by unconditionally switching to a kernel controlled page-table after relocation. This makes sure we can make changes to the mapping when necessary, for example map pages unencrypted in SEV and SEV-ES guests. Also remove the debug_putstr() calls in initialize_identity_maps() because the function now runs before console_init() is called. Signed-off-by: Joerg Roedel Reviewed-by: Kees Cook --- arch/x86/boot/compressed/head_64.S | 3 +- arch/x86/boot/compressed/ident_map_64.c | 51 +++++++++++++++---------- arch/x86/boot/compressed/kaslr.c | 3 -- 3 files changed, 32 insertions(+), 25 deletions(-) diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S index 4174d2f97b29..36f18d5592f4 100644 --- a/arch/x86/boot/compressed/head_64.S +++ b/arch/x86/boot/compressed/head_64.S @@ -543,10 +543,11 @@ SYM_FUNC_START_LOCAL_NOALIGN(.Lrelocated) rep stosq /* - * Load stage2 IDT + * Load stage2 IDT and switch to our own page-table */ pushq %rsi call load_stage2_idt + call initialize_identity_maps popq %rsi /* diff --git a/arch/x86/boot/compressed/ident_map_64.c b/arch/x86/boot/compressed/ident_map_64.c index e3d980ae9c2b..ecf9353b064d 100644 --- a/arch/x86/boot/compressed/ident_map_64.c +++ b/arch/x86/boot/compressed/ident_map_64.c @@ -86,9 +86,31 @@ phys_addr_t physical_mask = (1ULL << __PHYSICAL_MASK_SHIFT) - 1; */ static struct x86_mapping_info mapping_info; +/* + * Adds the specified range to what will become the new identity mappings. + * Once all ranges have been added, the new mapping is activated by calling + * finalize_identity_maps() below. + */ +void add_identity_map(unsigned long start, unsigned long size) +{ + unsigned long end = start + size; + + /* Align boundary to 2M. */ + start = round_down(start, PMD_SIZE); + end = round_up(end, PMD_SIZE); + if (start >= end) + return; + + /* Build the mapping. */ + kernel_ident_mapping_init(&mapping_info, (pgd_t *)top_level_pgt, + start, end); +} + /* Locates and clears a region for a new top level page table. */ void initialize_identity_maps(void) { + unsigned long start, size; + /* If running as an SEV guest, the encryption mask is required. */ set_sev_encryption_mask(); @@ -121,37 +143,24 @@ void initialize_identity_maps(void) */ top_level_pgt = read_cr3_pa(); if (p4d_offset((pgd_t *)top_level_pgt, 0) == (p4d_t *)_pgtable) { - debug_putstr("booted via startup_32()\n"); pgt_data.pgt_buf = _pgtable + BOOT_INIT_PGT_SIZE; pgt_data.pgt_buf_size = BOOT_PGT_SIZE - BOOT_INIT_PGT_SIZE; memset(pgt_data.pgt_buf, 0, pgt_data.pgt_buf_size); } else { - debug_putstr("booted via startup_64()\n"); pgt_data.pgt_buf = _pgtable; pgt_data.pgt_buf_size = BOOT_PGT_SIZE; memset(pgt_data.pgt_buf, 0, pgt_data.pgt_buf_size); top_level_pgt = (unsigned long)alloc_pgt_page(&pgt_data); } -} -/* - * Adds the specified range to what will become the new identity mappings. - * Once all ranges have been added, the new mapping is activated by calling - * finalize_identity_maps() below. - */ -void add_identity_map(unsigned long start, unsigned long size) -{ - unsigned long end = start + size; - - /* Align boundary to 2M. */ - start = round_down(start, PMD_SIZE); - end = round_up(end, PMD_SIZE); - if (start >= end) - return; - - /* Build the mapping. */ - kernel_ident_mapping_init(&mapping_info, (pgd_t *)top_level_pgt, - start, end); + /* + * New page-table is set up - map the kernel image and load it + * into cr3. + */ + start = (unsigned long)_head; + size = _end - _head; + add_identity_map(start, size); + write_cr3(top_level_pgt); } /* diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c index 7c61a8c5b9cf..856dc1c9bb0d 100644 --- a/arch/x86/boot/compressed/kaslr.c +++ b/arch/x86/boot/compressed/kaslr.c @@ -903,9 +903,6 @@ void choose_random_location(unsigned long input, boot_params->hdr.loadflags |= KASLR_FLAG; - /* Prepare to add new identity pagetables on demand. */ - initialize_identity_maps(); - /* Record the various known unsafe memory ranges. */ mem_avoid_init(input, input_size, *output); From patchwork Tue Jul 14 12:08:18 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662641 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id EE60B13A4 for ; Tue, 14 Jul 2020 12:16:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E13DB217A0 for ; Tue, 14 Jul 2020 12:16:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728968AbgGNMQa (ORCPT ); Tue, 14 Jul 2020 08:16:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60624 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728250AbgGNMKp (ORCPT ); Tue, 14 Jul 2020 08:10:45 -0400 Received: from theia.8bytes.org (8bytes.org [IPv6:2a01:238:4383:600:38bc:a715:4b6d:a889]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0BED3C08C5C1; Tue, 14 Jul 2020 05:10:45 -0700 (PDT) Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 87F996B2; Tue, 14 Jul 2020 14:10:41 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 16/75] x86/boot/compressed/64: Don't pre-map memory in KASLR code Date: Tue, 14 Jul 2020 14:08:18 +0200 Message-Id: <20200714120917.11253-17-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel With the page-fault handler in place the identity mapping can be built on-demand. So remove the code which manually creates the mappings and unexport/remove the functions used for it. Signed-off-by: Joerg Roedel Reviewed-by: Kees Cook --- arch/x86/boot/compressed/ident_map_64.c | 6 ++---- arch/x86/boot/compressed/kaslr.c | 24 +----------------------- arch/x86/boot/compressed/misc.h | 10 ---------- 3 files changed, 3 insertions(+), 37 deletions(-) diff --git a/arch/x86/boot/compressed/ident_map_64.c b/arch/x86/boot/compressed/ident_map_64.c index ecf9353b064d..c63257bf8373 100644 --- a/arch/x86/boot/compressed/ident_map_64.c +++ b/arch/x86/boot/compressed/ident_map_64.c @@ -87,11 +87,9 @@ phys_addr_t physical_mask = (1ULL << __PHYSICAL_MASK_SHIFT) - 1; static struct x86_mapping_info mapping_info; /* - * Adds the specified range to what will become the new identity mappings. - * Once all ranges have been added, the new mapping is activated by calling - * finalize_identity_maps() below. + * Adds the specified range to the identity mappings. */ -void add_identity_map(unsigned long start, unsigned long size) +static void add_identity_map(unsigned long start, unsigned long size) { unsigned long end = start + size; diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c index 856dc1c9bb0d..c466fb738de0 100644 --- a/arch/x86/boot/compressed/kaslr.c +++ b/arch/x86/boot/compressed/kaslr.c @@ -399,8 +399,6 @@ static void mem_avoid_init(unsigned long input, unsigned long input_size, */ mem_avoid[MEM_AVOID_ZO_RANGE].start = input; mem_avoid[MEM_AVOID_ZO_RANGE].size = (output + init_size) - input; - add_identity_map(mem_avoid[MEM_AVOID_ZO_RANGE].start, - mem_avoid[MEM_AVOID_ZO_RANGE].size); /* Avoid initrd. */ initrd_start = (u64)boot_params->ext_ramdisk_image << 32; @@ -420,14 +418,10 @@ static void mem_avoid_init(unsigned long input, unsigned long input_size, ; mem_avoid[MEM_AVOID_CMDLINE].start = cmd_line; mem_avoid[MEM_AVOID_CMDLINE].size = cmd_line_size; - add_identity_map(mem_avoid[MEM_AVOID_CMDLINE].start, - mem_avoid[MEM_AVOID_CMDLINE].size); /* Avoid boot parameters. */ mem_avoid[MEM_AVOID_BOOTPARAMS].start = (unsigned long)boot_params; mem_avoid[MEM_AVOID_BOOTPARAMS].size = sizeof(*boot_params); - add_identity_map(mem_avoid[MEM_AVOID_BOOTPARAMS].start, - mem_avoid[MEM_AVOID_BOOTPARAMS].size); /* We don't need to set a mapping for setup_data. */ @@ -436,11 +430,6 @@ static void mem_avoid_init(unsigned long input, unsigned long input_size, /* Enumerate the immovable memory regions */ num_immovable_mem = count_immovable_mem_regions(); - -#ifdef CONFIG_X86_VERBOSE_BOOTUP - /* Make sure video RAM can be used. */ - add_identity_map(0, PMD_SIZE); -#endif } /* @@ -919,19 +908,8 @@ void choose_random_location(unsigned long input, warn("Physical KASLR disabled: no suitable memory region!"); } else { /* Update the new physical address location. */ - if (*output != random_addr) { - add_identity_map(random_addr, output_size); + if (*output != random_addr) *output = random_addr; - } - - /* - * This loads the identity mapping page table. - * This should only be done if a new physical address - * is found for the kernel, otherwise we should keep - * the old page table to make it be like the "nokaslr" - * case. - */ - finalize_identity_maps(); } diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h index 345c90fbc500..ea6174bad699 100644 --- a/arch/x86/boot/compressed/misc.h +++ b/arch/x86/boot/compressed/misc.h @@ -98,17 +98,7 @@ static inline void choose_random_location(unsigned long input, #endif #ifdef CONFIG_X86_64 -void initialize_identity_maps(void); -void add_identity_map(unsigned long start, unsigned long size); -void finalize_identity_maps(void); extern unsigned char _pgtable[]; -#else -static inline void initialize_identity_maps(void) -{ } -static inline void add_identity_map(unsigned long start, unsigned long size) -{ } -static inline void finalize_identity_maps(void) -{ } #endif #ifdef CONFIG_EARLY_PRINTK From patchwork Tue Jul 14 12:08:19 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662647 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 169BB13A4 for ; Tue, 14 Jul 2020 12:17:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 081B022404 for ; Tue, 14 Jul 2020 12:17:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728870AbgGNMQ4 (ORCPT ); Tue, 14 Jul 2020 08:16:56 -0400 Received: from 8bytes.org ([81.169.241.247]:53184 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728168AbgGNMKo (ORCPT ); Tue, 14 Jul 2020 08:10:44 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 10C596B1; Tue, 14 Jul 2020 14:10:42 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 17/75] x86/boot/compressed/64: Change add_identity_map() to take start and end Date: Tue, 14 Jul 2020 14:08:19 +0200 Message-Id: <20200714120917.11253-18-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Changing the function to take start and end as parameters instead of start and size simplifies the callers, which don't need to calculate the size if they already have start and end. Signed-off-by: Joerg Roedel Reviewed-by: Kees Cook --- arch/x86/boot/compressed/ident_map_64.c | 15 +++++---------- 1 file changed, 5 insertions(+), 10 deletions(-) diff --git a/arch/x86/boot/compressed/ident_map_64.c b/arch/x86/boot/compressed/ident_map_64.c index c63257bf8373..62e42c11a336 100644 --- a/arch/x86/boot/compressed/ident_map_64.c +++ b/arch/x86/boot/compressed/ident_map_64.c @@ -89,10 +89,8 @@ static struct x86_mapping_info mapping_info; /* * Adds the specified range to the identity mappings. */ -static void add_identity_map(unsigned long start, unsigned long size) +static void add_identity_map(unsigned long start, unsigned long end) { - unsigned long end = start + size; - /* Align boundary to 2M. */ start = round_down(start, PMD_SIZE); end = round_up(end, PMD_SIZE); @@ -107,8 +105,6 @@ static void add_identity_map(unsigned long start, unsigned long size) /* Locates and clears a region for a new top level page table. */ void initialize_identity_maps(void) { - unsigned long start, size; - /* If running as an SEV guest, the encryption mask is required. */ set_sev_encryption_mask(); @@ -155,9 +151,7 @@ void initialize_identity_maps(void) * New page-table is set up - map the kernel image and load it * into cr3. */ - start = (unsigned long)_head; - size = _end - _head; - add_identity_map(start, size); + add_identity_map((unsigned long)_head, (unsigned long)_end); write_cr3(top_level_pgt); } @@ -189,7 +183,8 @@ static void do_pf_error(const char *msg, unsigned long error_code, void do_boot_page_fault(struct pt_regs *regs, unsigned long error_code) { - unsigned long address = native_read_cr2(); + unsigned long address = native_read_cr2() & PMD_MASK; + unsigned long end = address + PMD_SIZE; /* * Check for unexpected error codes. Unexpected are: @@ -204,5 +199,5 @@ void do_boot_page_fault(struct pt_regs *regs, unsigned long error_code) * Error code is sane - now identity map the 2M region around * the faulting address. */ - add_identity_map(address & PMD_MASK, PMD_SIZE); + add_identity_map(address, end); } From patchwork Tue Jul 14 12:08:20 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662639 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 1406F13A4 for ; Tue, 14 Jul 2020 12:16:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 007772068F for ; Tue, 14 Jul 2020 12:16:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728944AbgGNMQ1 (ORCPT ); Tue, 14 Jul 2020 08:16:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60630 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728256AbgGNMKq (ORCPT ); Tue, 14 Jul 2020 08:10:46 -0400 Received: from theia.8bytes.org (8bytes.org [IPv6:2a01:238:4383:600:38bc:a715:4b6d:a889]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 30EC9C061755; Tue, 14 Jul 2020 05:10:46 -0700 (PDT) Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 95BFB6FA; Tue, 14 Jul 2020 14:10:42 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 18/75] x86/boot/compressed/64: Add stage1 #VC handler Date: Tue, 14 Jul 2020 14:08:20 +0200 Message-Id: <20200714120917.11253-19-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Add the first handler for #VC exceptions. At stage 1 there is no GHCB yet becaue the kernel might still be running on the EFI page table. The stage 1 handler is limited to the MSR based protocol to talk to the hypervisor and can only support CPUID exit-codes, but that is enough to get to stage 2. Signed-off-by: Joerg Roedel --- arch/x86/boot/compressed/Makefile | 1 + arch/x86/boot/compressed/idt_64.c | 4 ++ arch/x86/boot/compressed/idt_handlers_64.S | 4 ++ arch/x86/boot/compressed/misc.h | 1 + arch/x86/boot/compressed/sev-es.c | 45 +++++++++++++++ arch/x86/include/asm/msr-index.h | 1 + arch/x86/include/asm/sev-es.h | 37 ++++++++++++ arch/x86/include/asm/trapnr.h | 1 + arch/x86/kernel/sev-es-shared.c | 66 ++++++++++++++++++++++ 9 files changed, 160 insertions(+) create mode 100644 arch/x86/boot/compressed/sev-es.c create mode 100644 arch/x86/include/asm/sev-es.h create mode 100644 arch/x86/kernel/sev-es-shared.c diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile index c825c95d13b9..b66f393e5a87 100644 --- a/arch/x86/boot/compressed/Makefile +++ b/arch/x86/boot/compressed/Makefile @@ -87,6 +87,7 @@ ifdef CONFIG_X86_64 vmlinux-objs-y += $(obj)/idt_64.o $(obj)/idt_handlers_64.o vmlinux-objs-y += $(obj)/mem_encrypt.o vmlinux-objs-y += $(obj)/pgtable_64.o + vmlinux-objs-$(CONFIG_AMD_MEM_ENCRYPT) += $(obj)/sev-es.o endif vmlinux-objs-$(CONFIG_ACPI) += $(obj)/acpi.o diff --git a/arch/x86/boot/compressed/idt_64.c b/arch/x86/boot/compressed/idt_64.c index 5f083092a86d..f3ca7324be44 100644 --- a/arch/x86/boot/compressed/idt_64.c +++ b/arch/x86/boot/compressed/idt_64.c @@ -32,6 +32,10 @@ void load_stage1_idt(void) { boot_idt_desc.address = (unsigned long)boot_idt; + + if (IS_ENABLED(CONFIG_AMD_MEM_ENCRYPT)) + set_idt_entry(X86_TRAP_VC, boot_stage1_vc); + load_boot_idt(&boot_idt_desc); } diff --git a/arch/x86/boot/compressed/idt_handlers_64.S b/arch/x86/boot/compressed/idt_handlers_64.S index b20e57504a94..92eb4df478a1 100644 --- a/arch/x86/boot/compressed/idt_handlers_64.S +++ b/arch/x86/boot/compressed/idt_handlers_64.S @@ -70,3 +70,7 @@ SYM_FUNC_END(\name) .code64 EXCEPTION_HANDLER boot_page_fault do_boot_page_fault error_code=1 + +#ifdef CONFIG_AMD_MEM_ENCRYPT +EXCEPTION_HANDLER boot_stage1_vc do_vc_no_ghcb error_code=1 +#endif diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h index ea6174bad699..65da40777bc1 100644 --- a/arch/x86/boot/compressed/misc.h +++ b/arch/x86/boot/compressed/misc.h @@ -141,5 +141,6 @@ extern struct desc_ptr boot_idt_desc; /* IDT Entry Points */ void boot_page_fault(void); +void boot_stage1_vc(void); #endif /* BOOT_COMPRESSED_MISC_H */ diff --git a/arch/x86/boot/compressed/sev-es.c b/arch/x86/boot/compressed/sev-es.c new file mode 100644 index 000000000000..bb91cbb5920e --- /dev/null +++ b/arch/x86/boot/compressed/sev-es.c @@ -0,0 +1,45 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * AMD Encrypted Register State Support + * + * Author: Joerg Roedel + */ + +/* + * misc.h needs to be first because it knows how to include the other kernel + * headers in the pre-decompression code in a way that does not break + * compilation. + */ +#include "misc.h" + +#include +#include +#include +#include + +static inline u64 sev_es_rd_ghcb_msr(void) +{ + unsigned long low, high; + + asm volatile("rdmsr\n" : "=a" (low), "=d" (high) : + "c" (MSR_AMD64_SEV_ES_GHCB)); + + return ((high << 32) | low); +} + +static inline void sev_es_wr_ghcb_msr(u64 val) +{ + u32 low, high; + + low = val & 0xffffffffUL; + high = val >> 32; + + asm volatile("wrmsr\n" : : "c" (MSR_AMD64_SEV_ES_GHCB), + "a"(low), "d" (high) : "memory"); +} + +#undef __init +#define __init + +/* Include code for early handlers */ +#include "../../kernel/sev-es-shared.c" diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h index e8370e64a155..2816eb01463f 100644 --- a/arch/x86/include/asm/msr-index.h +++ b/arch/x86/include/asm/msr-index.h @@ -448,6 +448,7 @@ #define MSR_AMD64_IBSBRTARGET 0xc001103b #define MSR_AMD64_IBSOPDATA4 0xc001103d #define MSR_AMD64_IBS_REG_COUNT_MAX 8 /* includes MSR_AMD64_IBSBRTARGET */ +#define MSR_AMD64_SEV_ES_GHCB 0xc0010130 #define MSR_AMD64_SEV 0xc0010131 #define MSR_AMD64_SEV_ENABLED_BIT 0 #define MSR_AMD64_SEV_ENABLED BIT_ULL(MSR_AMD64_SEV_ENABLED_BIT) diff --git a/arch/x86/include/asm/sev-es.h b/arch/x86/include/asm/sev-es.h new file mode 100644 index 000000000000..5d49a8a429d3 --- /dev/null +++ b/arch/x86/include/asm/sev-es.h @@ -0,0 +1,37 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * AMD Encrypted Register State Support + * + * Author: Joerg Roedel + */ + +#ifndef __ASM_ENCRYPTED_STATE_H +#define __ASM_ENCRYPTED_STATE_H + +#include + +#define GHCB_SEV_CPUID_REQ 0x004UL +#define GHCB_CPUID_REQ_EAX 0 +#define GHCB_CPUID_REQ_EBX 1 +#define GHCB_CPUID_REQ_ECX 2 +#define GHCB_CPUID_REQ_EDX 3 +#define GHCB_CPUID_REQ(fn, reg) (GHCB_SEV_CPUID_REQ | \ + (((unsigned long)reg & 3) << 30) | \ + (((unsigned long)fn) << 32)) + +#define GHCB_SEV_CPUID_RESP 0x005UL +#define GHCB_SEV_TERMINATE 0x100UL + +#define GHCB_SEV_GHCB_RESP_CODE(v) ((v) & 0xfff) +#define VMGEXIT() { asm volatile("rep; vmmcall\n\r"); } + +void __init do_vc_no_ghcb(struct pt_regs *regs, unsigned long exit_code); + +static inline u64 lower_bits(u64 val, unsigned int bits) +{ + u64 mask = (1ULL << bits) - 1; + + return (val & mask); +} + +#endif diff --git a/arch/x86/include/asm/trapnr.h b/arch/x86/include/asm/trapnr.h index 082f45631fa9..f5d2325aa0b7 100644 --- a/arch/x86/include/asm/trapnr.h +++ b/arch/x86/include/asm/trapnr.h @@ -26,6 +26,7 @@ #define X86_TRAP_XF 19 /* SIMD Floating-Point Exception */ #define X86_TRAP_VE 20 /* Virtualization Exception */ #define X86_TRAP_CP 21 /* Control Protection Exception */ +#define X86_TRAP_VC 29 /* VMM Communication Exception */ #define X86_TRAP_IRET 32 /* IRET Exception */ #endif diff --git a/arch/x86/kernel/sev-es-shared.c b/arch/x86/kernel/sev-es-shared.c new file mode 100644 index 000000000000..0bea32341afa --- /dev/null +++ b/arch/x86/kernel/sev-es-shared.c @@ -0,0 +1,66 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * AMD Encrypted Register State Support + * + * Author: Joerg Roedel + * + * This file is not compiled stand-alone. It contains code shared + * between the pre-decompression boot code and the running Linux kernel + * and is included directly into both code-bases. + */ + +/* + * Boot VC Handler - This is the first VC handler during boot, there is no GHCB + * page yet, so it only supports the MSR based communication with the + * hypervisor and only the CPUID exit-code. + */ +void __init do_vc_no_ghcb(struct pt_regs *regs, unsigned long exit_code) +{ + unsigned int fn = lower_bits(regs->ax, 32); + unsigned long val; + + /* Only CPUID is supported via MSR protocol */ + if (exit_code != SVM_EXIT_CPUID) + goto fail; + + sev_es_wr_ghcb_msr(GHCB_CPUID_REQ(fn, GHCB_CPUID_REQ_EAX)); + VMGEXIT(); + val = sev_es_rd_ghcb_msr(); + if (GHCB_SEV_GHCB_RESP_CODE(val) != GHCB_SEV_CPUID_RESP) + goto fail; + regs->ax = val >> 32; + + sev_es_wr_ghcb_msr(GHCB_CPUID_REQ(fn, GHCB_CPUID_REQ_EBX)); + VMGEXIT(); + val = sev_es_rd_ghcb_msr(); + if (GHCB_SEV_GHCB_RESP_CODE(val) != GHCB_SEV_CPUID_RESP) + goto fail; + regs->bx = val >> 32; + + sev_es_wr_ghcb_msr(GHCB_CPUID_REQ(fn, GHCB_CPUID_REQ_ECX)); + VMGEXIT(); + val = sev_es_rd_ghcb_msr(); + if (GHCB_SEV_GHCB_RESP_CODE(val) != GHCB_SEV_CPUID_RESP) + goto fail; + regs->cx = val >> 32; + + sev_es_wr_ghcb_msr(GHCB_CPUID_REQ(fn, GHCB_CPUID_REQ_EDX)); + VMGEXIT(); + val = sev_es_rd_ghcb_msr(); + if (GHCB_SEV_GHCB_RESP_CODE(val) != GHCB_SEV_CPUID_RESP) + goto fail; + regs->dx = val >> 32; + + /* Skip over the CPUID two-byte opcode */ + regs->ip += 2; + + return; + +fail: + sev_es_wr_ghcb_msr(GHCB_SEV_TERMINATE); + VMGEXIT(); + + /* Shouldn't get here - if we do halt the machine */ + while (true) + asm volatile("hlt\n"); +} From patchwork Tue Jul 14 12:08:21 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662649 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id EC4E913B4 for ; Tue, 14 Jul 2020 12:17:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D4F40217A0 for ; Tue, 14 Jul 2020 12:17:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728532AbgGNMQ4 (ORCPT ); Tue, 14 Jul 2020 08:16:56 -0400 Received: from 8bytes.org ([81.169.241.247]:52864 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728246AbgGNMKp (ORCPT ); Tue, 14 Jul 2020 08:10:45 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 2E6786B4; Tue, 14 Jul 2020 14:10:43 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 19/75] x86/boot/compressed/64: Call set_sev_encryption_mask earlier Date: Tue, 14 Jul 2020 14:08:21 +0200 Message-Id: <20200714120917.11253-20-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Call set_sev_encryption_mask() while still on the stage 1 #VC-handler, because the stage 2 handler needs our own page-tables to be set up, to which calling set_sev_encryption_mask() is a prerequisite. Signed-off-by: Joerg Roedel --- arch/x86/boot/compressed/head_64.S | 8 +++++++- arch/x86/boot/compressed/ident_map_64.c | 3 --- 2 files changed, 7 insertions(+), 4 deletions(-) diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S index 36f18d5592f4..963bf2ce11cf 100644 --- a/arch/x86/boot/compressed/head_64.S +++ b/arch/x86/boot/compressed/head_64.S @@ -543,9 +543,15 @@ SYM_FUNC_START_LOCAL_NOALIGN(.Lrelocated) rep stosq /* - * Load stage2 IDT and switch to our own page-table + * If running as an SEV guest, the encryption mask is required in the + * page-table setup code below. When the guest also has SEV-ES enabled + * set_sev_encryption_mask() will cause #VC exceptions, but the stage2 + * handler can't map its GHCB because the page-table is not set up yet. + * So set up the encryption mask here while still on the stage1 #VC + * handler. Then load stage2 IDT and switch to our own page-table. */ pushq %rsi + call set_sev_encryption_mask call load_stage2_idt call initialize_identity_maps popq %rsi diff --git a/arch/x86/boot/compressed/ident_map_64.c b/arch/x86/boot/compressed/ident_map_64.c index 62e42c11a336..b4f2a5f503cd 100644 --- a/arch/x86/boot/compressed/ident_map_64.c +++ b/arch/x86/boot/compressed/ident_map_64.c @@ -105,9 +105,6 @@ static void add_identity_map(unsigned long start, unsigned long end) /* Locates and clears a region for a new top level page table. */ void initialize_identity_maps(void) { - /* If running as an SEV guest, the encryption mask is required. */ - set_sev_encryption_mask(); - /* Exclude the encryption mask from __PHYSICAL_MASK */ physical_mask &= ~sme_me_mask; From patchwork Tue Jul 14 12:08:22 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662643 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 27CCB13A4 for ; Tue, 14 Jul 2020 12:16:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1995A223C6 for ; Tue, 14 Jul 2020 12:16:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728952AbgGNMQ3 (ORCPT ); Tue, 14 Jul 2020 08:16:29 -0400 Received: from 8bytes.org ([81.169.241.247]:52918 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728248AbgGNMKp (ORCPT ); Tue, 14 Jul 2020 08:10:45 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id B74997DD; Tue, 14 Jul 2020 14:10:43 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 20/75] x86/boot/compressed/64: Check return value of kernel_ident_mapping_init() Date: Tue, 14 Jul 2020 14:08:22 +0200 Message-Id: <20200714120917.11253-21-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel The function can fail to create an identity mapping, check for that and bail out if it happens. Signed-off-by: Joerg Roedel --- arch/x86/boot/compressed/ident_map_64.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/arch/x86/boot/compressed/ident_map_64.c b/arch/x86/boot/compressed/ident_map_64.c index b4f2a5f503cd..aa91bebc0fe9 100644 --- a/arch/x86/boot/compressed/ident_map_64.c +++ b/arch/x86/boot/compressed/ident_map_64.c @@ -91,6 +91,8 @@ static struct x86_mapping_info mapping_info; */ static void add_identity_map(unsigned long start, unsigned long end) { + int ret; + /* Align boundary to 2M. */ start = round_down(start, PMD_SIZE); end = round_up(end, PMD_SIZE); @@ -98,8 +100,9 @@ static void add_identity_map(unsigned long start, unsigned long end) return; /* Build the mapping. */ - kernel_ident_mapping_init(&mapping_info, (pgd_t *)top_level_pgt, - start, end); + ret = kernel_ident_mapping_init(&mapping_info, (pgd_t *)top_level_pgt, start, end); + if (ret) + error("Error: kernel_ident_mapping_init() failed\n"); } /* Locates and clears a region for a new top level page table. */ From patchwork Tue Jul 14 12:08:23 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662637 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 8C61D13B4 for ; Tue, 14 Jul 2020 12:16:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7EB1E22404 for ; Tue, 14 Jul 2020 12:16:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728270AbgGNMKt (ORCPT ); Tue, 14 Jul 2020 08:10:49 -0400 Received: from 8bytes.org ([81.169.241.247]:52886 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728253AbgGNMKr (ORCPT ); Tue, 14 Jul 2020 08:10:47 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 405727BC; Tue, 14 Jul 2020 14:10:44 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 21/75] x86/boot/compressed/64: Add set_page_en/decrypted() helpers Date: Tue, 14 Jul 2020 14:08:23 +0200 Message-Id: <20200714120917.11253-22-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel The functions are needed to map the GHCB for SEV-ES guests. The GHCB is used for communication with the hypervisor, so its content must not be encrypted. After the GHCB is not needed anymore it must be mapped encrypted again so that the running kernel image can safely re-use the memory. Signed-off-by: Joerg Roedel --- arch/x86/boot/compressed/ident_map_64.c | 133 ++++++++++++++++++++++++ arch/x86/boot/compressed/misc.h | 2 + 2 files changed, 135 insertions(+) diff --git a/arch/x86/boot/compressed/ident_map_64.c b/arch/x86/boot/compressed/ident_map_64.c index aa91bebc0fe9..05742f641a06 100644 --- a/arch/x86/boot/compressed/ident_map_64.c +++ b/arch/x86/boot/compressed/ident_map_64.c @@ -24,6 +24,7 @@ /* These actually do the work of building the kernel identity maps. */ #include +#include #include #include #include @@ -165,6 +166,138 @@ void finalize_identity_maps(void) write_cr3(top_level_pgt); } +static pte_t *split_large_pmd(struct x86_mapping_info *info, + pmd_t *pmdp, unsigned long __address) +{ + unsigned long page_flags; + unsigned long address; + pte_t *pte; + pmd_t pmd; + int i; + + pte = (pte_t *)info->alloc_pgt_page(info->context); + if (!pte) + return NULL; + + address = __address & PMD_MASK; + /* No large page - clear PSE flag */ + page_flags = info->page_flag & ~_PAGE_PSE; + + /* Populate the PTEs */ + for (i = 0; i < PTRS_PER_PMD; i++) { + set_pte(&pte[i], __pte(address | page_flags)); + address += PAGE_SIZE; + } + + /* + * Ideally we need to clear the large PMD first and do a TLB + * flush before we write the new PMD. But the 2M range of the + * PMD might contain the code we execute and/or the stack + * we are on, so we can't do that. But that should be safe here + * because we are going from large to small mappings and we are + * also the only user of the page-table, so there is no chance + * of a TLB multihit. + */ + pmd = __pmd((unsigned long)pte | info->kernpg_flag); + set_pmd(pmdp, pmd); + /* Flush TLB to establish the new PMD */ + write_cr3(top_level_pgt); + + return pte + pte_index(__address); +} + +static void clflush_page(unsigned long address) +{ + unsigned int flush_size; + char *cl, *start, *end; + + /* + * Hardcode cl-size to 64 - CPUID can't be used here because that might + * cause another #VC exception and the GHCB is not ready to use yet. + */ + flush_size = 64; + start = (char *)(address & PAGE_MASK); + end = start + PAGE_SIZE; + + /* + * First make sure there are no pending writes on the cache-lines to + * flush. + */ + asm volatile("mfence" : : : "memory"); + + for (cl = start; cl != end; cl += flush_size) + clflush(cl); +} + +static int set_clr_page_flags(struct x86_mapping_info *info, + unsigned long address, + pteval_t set, pteval_t clr) +{ + pgd_t *pgdp = (pgd_t *)top_level_pgt; + p4d_t *p4dp; + pud_t *pudp; + pmd_t *pmdp; + pte_t *ptep, pte; + + /* + * First make sure there is a PMD mapping for 'address'. + * It should already exist, but keep things generic. + * + * To map the page just read from it and fault it in if there is no + * mapping yet. add_identity_map() can't be called here because that + * would unconditionally map the address on PMD level, destroying any + * PTE-level mappings that might already exist. Use assembly here so + * the access won't be optimized away. + */ + asm volatile("mov %[address], %%r9" + :: [address] "g" (*(unsigned long *)address) + : "r9", "memory"); + + /* + * The page is mapped at least with PMD size - so skip checks and walk + * directly to the PMD. + */ + p4dp = p4d_offset(pgdp, address); + pudp = pud_offset(p4dp, address); + pmdp = pmd_offset(pudp, address); + + if (pmd_large(*pmdp)) + ptep = split_large_pmd(info, pmdp, address); + else + ptep = pte_offset_kernel(pmdp, address); + + if (!ptep) + return -ENOMEM; + + /* + * Changing encryption attributes of a page requires to flush it from + * the caches. + */ + if ((set | clr) & _PAGE_ENC) + clflush_page(address); + + /* Update PTE */ + pte = *ptep; + pte = pte_set_flags(pte, set); + pte = pte_clear_flags(pte, clr); + set_pte(ptep, pte); + + /* Flush TLB after changing encryption attribute */ + write_cr3(top_level_pgt); + + return 0; +} + +int set_page_decrypted(unsigned long address) +{ + return set_clr_page_flags(&mapping_info, address, 0, _PAGE_ENC); +} + +int set_page_encrypted(unsigned long address) +{ + return set_clr_page_flags(&mapping_info, address, _PAGE_ENC, 0); +} + static void do_pf_error(const char *msg, unsigned long error_code, unsigned long address, unsigned long ip) { diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h index 65da40777bc1..5e569e8a7d75 100644 --- a/arch/x86/boot/compressed/misc.h +++ b/arch/x86/boot/compressed/misc.h @@ -98,6 +98,8 @@ static inline void choose_random_location(unsigned long input, #endif #ifdef CONFIG_X86_64 +extern int set_page_decrypted(unsigned long address); +extern int set_page_encrypted(unsigned long address); extern unsigned char _pgtable[]; #endif From patchwork Tue Jul 14 12:08:24 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662635 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A393913A4 for ; Tue, 14 Jul 2020 12:16:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8B6E8217A0 for ; Tue, 14 Jul 2020 12:16:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728278AbgGNMKt (ORCPT ); Tue, 14 Jul 2020 08:10:49 -0400 Received: from 8bytes.org ([81.169.241.247]:53184 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728257AbgGNMKr (ORCPT ); Tue, 14 Jul 2020 08:10:47 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id C975397F; Tue, 14 Jul 2020 14:10:44 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 22/75] x86/boot/compressed/64: Setup GHCB Based VC Exception handler Date: Tue, 14 Jul 2020 14:08:24 +0200 Message-Id: <20200714120917.11253-23-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Install an exception handler for #VC exception that uses a GHCB. Also add the infrastructure for handling different exit-codes by decoding the instruction that caused the exception and error handling. Signed-off-by: Joerg Roedel --- arch/x86/Kconfig | 1 + arch/x86/boot/compressed/Makefile | 3 + arch/x86/boot/compressed/idt_64.c | 4 + arch/x86/boot/compressed/idt_handlers_64.S | 3 +- arch/x86/boot/compressed/misc.c | 7 + arch/x86/boot/compressed/misc.h | 7 + arch/x86/boot/compressed/sev-es.c | 111 +++++++++++++++ arch/x86/include/asm/sev-es.h | 39 ++++++ arch/x86/include/uapi/asm/svm.h | 1 + arch/x86/kernel/sev-es-shared.c | 154 +++++++++++++++++++++ 10 files changed, 329 insertions(+), 1 deletion(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 883da0abf779..0c3401decd10 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1520,6 +1520,7 @@ config AMD_MEM_ENCRYPT select DYNAMIC_PHYSICAL_MASK select ARCH_USE_MEMREMAP_PROT select ARCH_HAS_FORCE_DMA_UNENCRYPTED + select INSTRUCTION_DECODER help Say yes to enable support for the encryption of system memory. This requires an AMD processor that supports Secure Memory diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile index b66f393e5a87..601fc7abf8ac 100644 --- a/arch/x86/boot/compressed/Makefile +++ b/arch/x86/boot/compressed/Makefile @@ -43,6 +43,9 @@ KBUILD_CFLAGS += -Wno-pointer-sign KBUILD_CFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=) KBUILD_CFLAGS += -fno-asynchronous-unwind-tables +# sev-es.c inludes generated $(objtree)/arch/x86/lib/inat-tables.c +CFLAGS_sev-es.o += -I$(objtree)/arch/x86/lib/ + KBUILD_AFLAGS := $(KBUILD_CFLAGS) -D__ASSEMBLY__ GCOV_PROFILE := n UBSAN_SANITIZE :=n diff --git a/arch/x86/boot/compressed/idt_64.c b/arch/x86/boot/compressed/idt_64.c index f3ca7324be44..804a502ee0d2 100644 --- a/arch/x86/boot/compressed/idt_64.c +++ b/arch/x86/boot/compressed/idt_64.c @@ -46,5 +46,9 @@ void load_stage2_idt(void) set_idt_entry(X86_TRAP_PF, boot_page_fault); +#ifdef CONFIG_AMD_MEM_ENCRYPT + set_idt_entry(X86_TRAP_VC, boot_stage2_vc); +#endif + load_boot_idt(&boot_idt_desc); } diff --git a/arch/x86/boot/compressed/idt_handlers_64.S b/arch/x86/boot/compressed/idt_handlers_64.S index 92eb4df478a1..22890e199f5b 100644 --- a/arch/x86/boot/compressed/idt_handlers_64.S +++ b/arch/x86/boot/compressed/idt_handlers_64.S @@ -72,5 +72,6 @@ SYM_FUNC_END(\name) EXCEPTION_HANDLER boot_page_fault do_boot_page_fault error_code=1 #ifdef CONFIG_AMD_MEM_ENCRYPT -EXCEPTION_HANDLER boot_stage1_vc do_vc_no_ghcb error_code=1 +EXCEPTION_HANDLER boot_stage1_vc do_vc_no_ghcb error_code=1 +EXCEPTION_HANDLER boot_stage2_vc do_boot_stage2_vc error_code=1 #endif diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c index 9652d5c2afda..dba49e75095a 100644 --- a/arch/x86/boot/compressed/misc.c +++ b/arch/x86/boot/compressed/misc.c @@ -441,6 +441,13 @@ asmlinkage __visible void *extract_kernel(void *rmode, memptr heap, parse_elf(output); handle_relocations(output, output_len, virt_addr); debug_putstr("done.\nBooting the kernel.\n"); + + /* + * Flush GHCB from cache and map it encrypted again when running as + * SEV-ES guest. + */ + sev_es_shutdown_ghcb(); + return output; } diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h index 5e569e8a7d75..4d37a28370ed 100644 --- a/arch/x86/boot/compressed/misc.h +++ b/arch/x86/boot/compressed/misc.h @@ -115,6 +115,12 @@ static inline void console_init(void) void set_sev_encryption_mask(void); +#ifdef CONFIG_AMD_MEM_ENCRYPT +void sev_es_shutdown_ghcb(void); +#else +static inline void sev_es_shutdown_ghcb(void) { } +#endif + /* acpi.c */ #ifdef CONFIG_ACPI acpi_physical_address get_rsdp_addr(void); @@ -144,5 +150,6 @@ extern struct desc_ptr boot_idt_desc; /* IDT Entry Points */ void boot_page_fault(void); void boot_stage1_vc(void); +void boot_stage2_vc(void); #endif /* BOOT_COMPRESSED_MISC_H */ diff --git a/arch/x86/boot/compressed/sev-es.c b/arch/x86/boot/compressed/sev-es.c index bb91cbb5920e..7e2cec170026 100644 --- a/arch/x86/boot/compressed/sev-es.c +++ b/arch/x86/boot/compressed/sev-es.c @@ -13,10 +13,17 @@ #include "misc.h" #include +#include +#include #include #include #include +#include "error.h" + +struct ghcb boot_ghcb_page __aligned(PAGE_SIZE); +struct ghcb *boot_ghcb; + static inline u64 sev_es_rd_ghcb_msr(void) { unsigned long low, high; @@ -38,8 +45,112 @@ static inline void sev_es_wr_ghcb_msr(u64 val) "a"(low), "d" (high) : "memory"); } +static enum es_result vc_decode_insn(struct es_em_ctxt *ctxt) +{ + char buffer[MAX_INSN_SIZE]; + enum es_result ret; + + memcpy(buffer, (unsigned char *)ctxt->regs->ip, MAX_INSN_SIZE); + + insn_init(&ctxt->insn, buffer, MAX_INSN_SIZE, 1); + insn_get_length(&ctxt->insn); + + ret = ctxt->insn.immediate.got ? ES_OK : ES_DECODE_FAILED; + + return ret; +} + +static enum es_result vc_write_mem(struct es_em_ctxt *ctxt, + void *dst, char *buf, size_t size) +{ + memcpy(dst, buf, size); + + return ES_OK; +} + +static enum es_result vc_read_mem(struct es_em_ctxt *ctxt, + void *src, char *buf, size_t size) +{ + memcpy(buf, src, size); + + return ES_OK; +} + #undef __init +#undef __pa #define __init +#define __pa(x) ((unsigned long)(x)) + +#define __BOOT_COMPRESSED + +/* Basic instruction decoding support needed */ +#include "../../lib/inat.c" +#include "../../lib/insn.c" /* Include code for early handlers */ #include "../../kernel/sev-es-shared.c" + +static bool early_sev_es_setup_ghcb(void) +{ + if (!sev_es_negotiate_protocol()) + sev_es_terminate(GHCB_SEV_ES_REASON_PROTOCOL_UNSUPPORTED); + + if (set_page_decrypted((unsigned long)&boot_ghcb_page)) + return false; + + /* Page is now mapped decrypted, clear it */ + memset(&boot_ghcb_page, 0, sizeof(boot_ghcb_page)); + + boot_ghcb = &boot_ghcb_page; + + /* Initialize lookup tables for the instruction decoder */ + inat_init_tables(); + + return true; +} + +void sev_es_shutdown_ghcb(void) +{ + if (!boot_ghcb) + return; + + /* + * GHCB Page must be flushed from the cache and mapped encrypted again. + * Otherwise the running kernel will see strange cache effects when + * trying to use that page. + */ + if (set_page_encrypted((unsigned long)&boot_ghcb_page)) + error("Can't map GHCB page encrypted"); +} + +void do_boot_stage2_vc(struct pt_regs *regs, unsigned long exit_code) +{ + struct es_em_ctxt ctxt; + enum es_result result; + + if (!boot_ghcb && !early_sev_es_setup_ghcb()) + sev_es_terminate(GHCB_SEV_ES_REASON_GENERAL_REQUEST); + + vc_ghcb_invalidate(boot_ghcb); + result = vc_init_em_ctxt(&ctxt, regs, exit_code); + if (result != ES_OK) + goto finish; + + switch (exit_code) { + default: + result = ES_UNSUPPORTED; + break; + } + +finish: + if (result == ES_OK) { + vc_finish_insn(&ctxt); + } else if (result != ES_RETRY) { + /* + * For now, just halt the machine. That makes debugging easier, + * later we just call sev_es_terminate() here. + */ + while (true) + asm volatile("hlt\n"); + } +} diff --git a/arch/x86/include/asm/sev-es.h b/arch/x86/include/asm/sev-es.h index 5d49a8a429d3..7c0807b84546 100644 --- a/arch/x86/include/asm/sev-es.h +++ b/arch/x86/include/asm/sev-es.h @@ -9,7 +9,14 @@ #define __ASM_ENCRYPTED_STATE_H #include +#include +#define GHCB_SEV_INFO 0x001UL +#define GHCB_SEV_INFO_REQ 0x002UL +#define GHCB_INFO(v) ((v) & 0xfffUL) +#define GHCB_PROTO_MAX(v) (((v) >> 48) & 0xffffUL) +#define GHCB_PROTO_MIN(v) (((v) >> 32) & 0xffffUL) +#define GHCB_PROTO_OUR 0x0001UL #define GHCB_SEV_CPUID_REQ 0x004UL #define GHCB_CPUID_REQ_EAX 0 #define GHCB_CPUID_REQ_EBX 1 @@ -19,12 +26,44 @@ (((unsigned long)reg & 3) << 30) | \ (((unsigned long)fn) << 32)) +#define GHCB_PROTOCOL_MAX 0x0001UL +#define GHCB_DEFAULT_USAGE 0x0000UL + #define GHCB_SEV_CPUID_RESP 0x005UL #define GHCB_SEV_TERMINATE 0x100UL +#define GHCB_SEV_TERMINATE_REASON(reason_set, reason_val) \ + (((((u64)reason_set) & 0x7) << 12) | \ + ((((u64)reason_val) & 0xff) << 16)) +#define GHCB_SEV_ES_REASON_GENERAL_REQUEST 0 +#define GHCB_SEV_ES_REASON_PROTOCOL_UNSUPPORTED 1 #define GHCB_SEV_GHCB_RESP_CODE(v) ((v) & 0xfff) #define VMGEXIT() { asm volatile("rep; vmmcall\n\r"); } +enum es_result { + ES_OK, /* All good */ + ES_UNSUPPORTED, /* Requested operation not supported */ + ES_VMM_ERROR, /* Unexpected state from the VMM */ + ES_DECODE_FAILED, /* Instruction decoding failed */ + ES_EXCEPTION, /* Instruction caused exception */ + ES_RETRY, /* Retry instruction emulation */ +}; + +struct es_fault_info { + unsigned long vector; + unsigned long error_code; + unsigned long cr2; +}; + +struct pt_regs; + +/* ES instruction emulation context */ +struct es_em_ctxt { + struct pt_regs *regs; + struct insn insn; + struct es_fault_info fi; +}; + void __init do_vc_no_ghcb(struct pt_regs *regs, unsigned long exit_code); static inline u64 lower_bits(u64 val, unsigned int bits) diff --git a/arch/x86/include/uapi/asm/svm.h b/arch/x86/include/uapi/asm/svm.h index 2e8a30f06c74..c68d1618c9b0 100644 --- a/arch/x86/include/uapi/asm/svm.h +++ b/arch/x86/include/uapi/asm/svm.h @@ -29,6 +29,7 @@ #define SVM_EXIT_WRITE_DR6 0x036 #define SVM_EXIT_WRITE_DR7 0x037 #define SVM_EXIT_EXCP_BASE 0x040 +#define SVM_EXIT_LAST_EXCP 0x05f #define SVM_EXIT_INTR 0x060 #define SVM_EXIT_NMI 0x061 #define SVM_EXIT_SMI 0x062 diff --git a/arch/x86/kernel/sev-es-shared.c b/arch/x86/kernel/sev-es-shared.c index 0bea32341afa..7ac6e6b0ae57 100644 --- a/arch/x86/kernel/sev-es-shared.c +++ b/arch/x86/kernel/sev-es-shared.c @@ -9,6 +9,118 @@ * and is included directly into both code-bases. */ +static void sev_es_terminate(unsigned int reason) +{ + u64 val = GHCB_SEV_TERMINATE; + + /* + * Tell the hypervisor what went wrong - only reason-set 0 is + * currently supported. + */ + val |= GHCB_SEV_TERMINATE_REASON(0, reason); + + /* Request Guest Termination from Hypvervisor */ + sev_es_wr_ghcb_msr(val); + VMGEXIT(); + + while (true) + asm volatile("hlt\n" : : : "memory"); +} + +static bool sev_es_negotiate_protocol(void) +{ + u64 val; + + /* Do the GHCB protocol version negotiation */ + sev_es_wr_ghcb_msr(GHCB_SEV_INFO_REQ); + VMGEXIT(); + val = sev_es_rd_ghcb_msr(); + + if (GHCB_INFO(val) != GHCB_SEV_INFO) + return false; + + if (GHCB_PROTO_MAX(val) < GHCB_PROTO_OUR || + GHCB_PROTO_MIN(val) > GHCB_PROTO_OUR) + return false; + + return true; +} + +static void vc_ghcb_invalidate(struct ghcb *ghcb) +{ + memset(ghcb->save.valid_bitmap, 0, sizeof(ghcb->save.valid_bitmap)); +} + +static bool vc_decoding_needed(unsigned long exit_code) +{ + /* Exceptions don't require to decode the instruction */ + return !(exit_code >= SVM_EXIT_EXCP_BASE && + exit_code <= SVM_EXIT_LAST_EXCP); +} + +static enum es_result vc_init_em_ctxt(struct es_em_ctxt *ctxt, + struct pt_regs *regs, + unsigned long exit_code) +{ + enum es_result ret = ES_OK; + + memset(ctxt, 0, sizeof(*ctxt)); + ctxt->regs = regs; + + if (vc_decoding_needed(exit_code)) + ret = vc_decode_insn(ctxt); + + return ret; +} + +static void vc_finish_insn(struct es_em_ctxt *ctxt) +{ + ctxt->regs->ip += ctxt->insn.length; +} + +static enum es_result sev_es_ghcb_hv_call(struct ghcb *ghcb, + struct es_em_ctxt *ctxt, + u64 exit_code, u64 exit_info_1, + u64 exit_info_2) +{ + enum es_result ret; + + /* Fill in protocol and format specifiers */ + ghcb->protocol_version = GHCB_PROTOCOL_MAX; + ghcb->ghcb_usage = GHCB_DEFAULT_USAGE; + + ghcb_set_sw_exit_code(ghcb, exit_code); + ghcb_set_sw_exit_info_1(ghcb, exit_info_1); + ghcb_set_sw_exit_info_2(ghcb, exit_info_2); + + sev_es_wr_ghcb_msr(__pa(ghcb)); + VMGEXIT(); + + if ((ghcb->save.sw_exit_info_1 & 0xffffffff) == 1) { + u64 info = ghcb->save.sw_exit_info_2; + unsigned long v; + + info = ghcb->save.sw_exit_info_2; + v = info & SVM_EVTINJ_VEC_MASK; + + /* Check if exception information from hypervisor is sane. */ + if ((info & SVM_EVTINJ_VALID) && + ((v == X86_TRAP_GP) || (v == X86_TRAP_UD)) && + ((info & SVM_EVTINJ_TYPE_MASK) == SVM_EVTINJ_TYPE_EXEPT)) { + ctxt->fi.vector = v; + if (info & SVM_EVTINJ_VALID_ERR) + ctxt->fi.error_code = info >> 32; + ret = ES_EXCEPTION; + } else { + ret = ES_VMM_ERROR; + } + } else { + ret = ES_OK; + } + + return ret; +} + /* * Boot VC Handler - This is the first VC handler during boot, there is no GHCB * page yet, so it only supports the MSR based communication with the @@ -64,3 +176,45 @@ void __init do_vc_no_ghcb(struct pt_regs *regs, unsigned long exit_code) while (true) asm volatile("hlt\n"); } + +static enum es_result vc_insn_string_read(struct es_em_ctxt *ctxt, + void *src, char *buf, + unsigned int data_size, + unsigned int count, + bool backwards) +{ + int i, b = backwards ? -1 : 1; + enum es_result ret = ES_OK; + + for (i = 0; i < count; i++) { + void *s = src + (i * data_size * b); + char *d = buf + (i * data_size); + + ret = vc_read_mem(ctxt, s, d, data_size); + if (ret != ES_OK) + break; + } + + return ret; +} + +static enum es_result vc_insn_string_write(struct es_em_ctxt *ctxt, + void *dst, char *buf, + unsigned int data_size, + unsigned int count, + bool backwards) +{ + int i, s = backwards ? -1 : 1; + enum es_result ret = ES_OK; + + for (i = 0; i < count; i++) { + void *d = dst + (i * data_size * s); + char *b = buf + (i * data_size); + + ret = vc_write_mem(ctxt, d, b, data_size); + if (ret != ES_OK) + break; + } + + return ret; +} From patchwork Tue Jul 14 12:08:25 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662529 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 7E47513B4 for ; Tue, 14 Jul 2020 12:10:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 64DD02225A for ; Tue, 14 Jul 2020 12:10:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728296AbgGNMKv (ORCPT ); Tue, 14 Jul 2020 08:10:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60640 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728272AbgGNMKt (ORCPT ); Tue, 14 Jul 2020 08:10:49 -0400 Received: from theia.8bytes.org (8bytes.org [IPv6:2a01:238:4383:600:38bc:a715:4b6d:a889]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1E0D6C061755; Tue, 14 Jul 2020 05:10:49 -0700 (PDT) Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 6066F93D; Tue, 14 Jul 2020 14:10:45 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 23/75] x86/boot/compressed/64: Unmap GHCB page before booting the kernel Date: Tue, 14 Jul 2020 14:08:25 +0200 Message-Id: <20200714120917.11253-24-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Force a page-fault on any further accesses to the GHCB page when they shouldn't happen anymore. This will catch the bugs where a #VC exception is raised when no one is expected anymore. Signed-off-by: Joerg Roedel --- arch/x86/boot/compressed/ident_map_64.c | 17 +++++++++++++++-- arch/x86/boot/compressed/misc.h | 6 ++++++ arch/x86/boot/compressed/sev-es.c | 14 ++++++++++++++ 3 files changed, 35 insertions(+), 2 deletions(-) diff --git a/arch/x86/boot/compressed/ident_map_64.c b/arch/x86/boot/compressed/ident_map_64.c index 05742f641a06..063a60edcf99 100644 --- a/arch/x86/boot/compressed/ident_map_64.c +++ b/arch/x86/boot/compressed/ident_map_64.c @@ -298,6 +298,11 @@ int set_page_encrypted(unsigned long address) return set_clr_page_flags(&mapping_info, address, _PAGE_ENC, 0); } +int set_page_non_present(unsigned long address) +{ + return set_clr_page_flags(&mapping_info, address, 0, _PAGE_PRESENT); +} + static void do_pf_error(const char *msg, unsigned long error_code, unsigned long address, unsigned long ip) { @@ -316,8 +321,14 @@ static void do_pf_error(const char *msg, unsigned long error_code, void do_boot_page_fault(struct pt_regs *regs, unsigned long error_code) { - unsigned long address = native_read_cr2() & PMD_MASK; - unsigned long end = address + PMD_SIZE; + unsigned long address = native_read_cr2(); + unsigned long end; + bool ghcb_fault; + + ghcb_fault = sev_es_check_ghcb_fault(address); + + address &= PMD_MASK; + end = address + PMD_SIZE; /* * Check for unexpected error codes. Unexpected are: @@ -327,6 +338,8 @@ void do_boot_page_fault(struct pt_regs *regs, unsigned long error_code) */ if (error_code & (X86_PF_PROT | X86_PF_USER | X86_PF_RSVD)) do_pf_error("Unexpected page-fault:", error_code, address, regs->ip); + else if (ghcb_fault) + do_pf_error("Page-fault on GHCB page:", error_code, address, regs->ip); /* * Error code is sane - now identity map the 2M region around diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h index 4d37a28370ed..2e5f82acc122 100644 --- a/arch/x86/boot/compressed/misc.h +++ b/arch/x86/boot/compressed/misc.h @@ -100,6 +100,7 @@ static inline void choose_random_location(unsigned long input, #ifdef CONFIG_X86_64 extern int set_page_decrypted(unsigned long address); extern int set_page_encrypted(unsigned long address); +extern int set_page_non_present(unsigned long address); extern unsigned char _pgtable[]; #endif @@ -117,8 +118,13 @@ void set_sev_encryption_mask(void); #ifdef CONFIG_AMD_MEM_ENCRYPT void sev_es_shutdown_ghcb(void); +extern bool sev_es_check_ghcb_fault(unsigned long address); #else static inline void sev_es_shutdown_ghcb(void) { } +static inline bool sev_es_check_ghcb_fault(unsigned long address) +{ + return false; +} #endif /* acpi.c */ diff --git a/arch/x86/boot/compressed/sev-es.c b/arch/x86/boot/compressed/sev-es.c index 7e2cec170026..e3abf8737015 100644 --- a/arch/x86/boot/compressed/sev-es.c +++ b/arch/x86/boot/compressed/sev-es.c @@ -121,6 +121,20 @@ void sev_es_shutdown_ghcb(void) */ if (set_page_encrypted((unsigned long)&boot_ghcb_page)) error("Can't map GHCB page encrypted"); + + /* + * GHCB page is mapped encrypted again and flushed from the cache. + * Mark it non-present now to catch bugs when #VC exceptions trigger + * after this point. + */ + if (set_page_non_present((unsigned long)&boot_ghcb_page)) + error("Can't unmap GHCB page"); +} + +bool sev_es_check_ghcb_fault(unsigned long address) +{ + /* Check whether the fault was on the GHCB page */ + return ((address & PAGE_MASK) == (unsigned long)&boot_ghcb_page); } void do_boot_stage2_vc(struct pt_regs *regs, unsigned long exit_code) From patchwork Tue Jul 14 12:08:26 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662631 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B7D6313A4 for ; Tue, 14 Jul 2020 12:16:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A4518207FB for ; Tue, 14 Jul 2020 12:16:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728288AbgGNMKu (ORCPT ); Tue, 14 Jul 2020 08:10:50 -0400 Received: from 8bytes.org ([81.169.241.247]:52918 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728177AbgGNMKs (ORCPT ); Tue, 14 Jul 2020 08:10:48 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id F3C559A9; Tue, 14 Jul 2020 14:10:45 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , Tom Lendacky , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 24/75] x86/sev-es: Add support for handling IOIO exceptions Date: Tue, 14 Jul 2020 14:08:26 +0200 Message-Id: <20200714120917.11253-25-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Tom Lendacky Add support for decoding and handling #VC exceptions for IOIO events. Signed-off-by: Tom Lendacky [ jroedel@suse.de: Adapted code to #VC handling framework ] Co-developed-by: Joerg Roedel Signed-off-by: Joerg Roedel --- arch/x86/boot/compressed/sev-es.c | 32 +++++ arch/x86/kernel/sev-es-shared.c | 214 ++++++++++++++++++++++++++++++ 2 files changed, 246 insertions(+) diff --git a/arch/x86/boot/compressed/sev-es.c b/arch/x86/boot/compressed/sev-es.c index e3abf8737015..4f2fc7a85c2f 100644 --- a/arch/x86/boot/compressed/sev-es.c +++ b/arch/x86/boot/compressed/sev-es.c @@ -24,6 +24,35 @@ struct ghcb boot_ghcb_page __aligned(PAGE_SIZE); struct ghcb *boot_ghcb; +/* + * Copy a version of this function here - insn-eval.c can't be used in + * pre-decompression code. + */ +static bool insn_has_rep_prefix(struct insn *insn) +{ + int i; + + insn_get_prefixes(insn); + + for (i = 0; i < insn->prefixes.nbytes; i++) { + insn_byte_t p = insn->prefixes.bytes[i]; + + if (p == 0xf2 || p == 0xf3) + return true; + } + + return false; +} + +/* + * Only a dummy for insn_get_seg_base() - Early boot-code is 64bit only and + * doesn't use segments. + */ +static unsigned long insn_get_seg_base(struct pt_regs *regs, int seg_reg_idx) +{ + return 0UL; +} + static inline u64 sev_es_rd_ghcb_msr(void) { unsigned long low, high; @@ -151,6 +180,9 @@ void do_boot_stage2_vc(struct pt_regs *regs, unsigned long exit_code) goto finish; switch (exit_code) { + case SVM_EXIT_IOIO: + result = vc_handle_ioio(boot_ghcb, &ctxt); + break; default: result = ES_UNSUPPORTED; break; diff --git a/arch/x86/kernel/sev-es-shared.c b/arch/x86/kernel/sev-es-shared.c index 7ac6e6b0ae57..66d60e34eba0 100644 --- a/arch/x86/kernel/sev-es-shared.c +++ b/arch/x86/kernel/sev-es-shared.c @@ -218,3 +218,217 @@ static enum es_result vc_insn_string_write(struct es_em_ctxt *ctxt, return ret; } + +#define IOIO_TYPE_STR BIT(2) +#define IOIO_TYPE_IN 1 +#define IOIO_TYPE_INS (IOIO_TYPE_IN | IOIO_TYPE_STR) +#define IOIO_TYPE_OUT 0 +#define IOIO_TYPE_OUTS (IOIO_TYPE_OUT | IOIO_TYPE_STR) + +#define IOIO_REP BIT(3) + +#define IOIO_ADDR_64 BIT(9) +#define IOIO_ADDR_32 BIT(8) +#define IOIO_ADDR_16 BIT(7) + +#define IOIO_DATA_32 BIT(6) +#define IOIO_DATA_16 BIT(5) +#define IOIO_DATA_8 BIT(4) + +#define IOIO_SEG_ES (0 << 10) +#define IOIO_SEG_DS (3 << 10) + +static enum es_result vc_ioio_exitinfo(struct es_em_ctxt *ctxt, u64 *exitinfo) +{ + struct insn *insn = &ctxt->insn; + *exitinfo = 0; + + switch (insn->opcode.bytes[0]) { + /* INS opcodes */ + case 0x6c: + case 0x6d: + *exitinfo |= IOIO_TYPE_INS; + *exitinfo |= IOIO_SEG_ES; + *exitinfo |= (ctxt->regs->dx & 0xffff) << 16; + break; + + /* OUTS opcodes */ + case 0x6e: + case 0x6f: + *exitinfo |= IOIO_TYPE_OUTS; + *exitinfo |= IOIO_SEG_DS; + *exitinfo |= (ctxt->regs->dx & 0xffff) << 16; + break; + + /* IN immediate opcodes */ + case 0xe4: + case 0xe5: + *exitinfo |= IOIO_TYPE_IN; + *exitinfo |= insn->immediate.value << 16; + break; + + /* OUT immediate opcodes */ + case 0xe6: + case 0xe7: + *exitinfo |= IOIO_TYPE_OUT; + *exitinfo |= insn->immediate.value << 16; + break; + + /* IN register opcodes */ + case 0xec: + case 0xed: + *exitinfo |= IOIO_TYPE_IN; + *exitinfo |= (ctxt->regs->dx & 0xffff) << 16; + break; + + /* OUT register opcodes */ + case 0xee: + case 0xef: + *exitinfo |= IOIO_TYPE_OUT; + *exitinfo |= (ctxt->regs->dx & 0xffff) << 16; + break; + + default: + return ES_DECODE_FAILED; + } + + switch (insn->opcode.bytes[0]) { + case 0x6c: + case 0x6e: + case 0xe4: + case 0xe6: + case 0xec: + case 0xee: + /* Single byte opcodes */ + *exitinfo |= IOIO_DATA_8; + break; + default: + /* Length determined by instruction parsing */ + *exitinfo |= (insn->opnd_bytes == 2) ? IOIO_DATA_16 + : IOIO_DATA_32; + } + switch (insn->addr_bytes) { + case 2: + *exitinfo |= IOIO_ADDR_16; + break; + case 4: + *exitinfo |= IOIO_ADDR_32; + break; + case 8: + *exitinfo |= IOIO_ADDR_64; + break; + } + + if (insn_has_rep_prefix(insn)) + *exitinfo |= IOIO_REP; + + return ES_OK; +} + +static enum es_result vc_handle_ioio(struct ghcb *ghcb, struct es_em_ctxt *ctxt) +{ + struct pt_regs *regs = ctxt->regs; + u64 exit_info_1, exit_info_2; + enum es_result ret; + + ret = vc_ioio_exitinfo(ctxt, &exit_info_1); + if (ret != ES_OK) + return ret; + + if (exit_info_1 & IOIO_TYPE_STR) { + + /* (REP) INS/OUTS */ + + bool df = ((regs->flags & X86_EFLAGS_DF) == X86_EFLAGS_DF); + unsigned int io_bytes, exit_bytes; + unsigned int ghcb_count, op_count; + unsigned long es_base; + u64 sw_scratch; + + /* + * For the string variants with rep prefix the amount of in/out + * operations per #VC exception is limited so that the kernel + * has a chance to take interrupts and re-schedule while the + * instruction is emulated. + */ + io_bytes = (exit_info_1 >> 4) & 0x7; + ghcb_count = sizeof(ghcb->shared_buffer) / io_bytes; + + op_count = (exit_info_1 & IOIO_REP) ? regs->cx : 1; + exit_info_2 = min(op_count, ghcb_count); + exit_bytes = exit_info_2 * io_bytes; + + es_base = insn_get_seg_base(ctxt->regs, INAT_SEG_REG_ES); + + /* Read bytes of OUTS into the shared buffer */ + if (!(exit_info_1 & IOIO_TYPE_IN)) { + ret = vc_insn_string_read(ctxt, + (void *)(es_base + regs->si), + ghcb->shared_buffer, io_bytes, + exit_info_2, df); + if (ret) + return ret; + } + + /* + * Issue an VMGEXIT to the HV to consume the bytes from the + * shared buffer or to have it write them into the shared buffer + * depending on the instruction: OUTS or INS. + */ + sw_scratch = __pa(ghcb) + offsetof(struct ghcb, shared_buffer); + ghcb_set_sw_scratch(ghcb, sw_scratch); + ret = sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_IOIO, + exit_info_1, exit_info_2); + if (ret != ES_OK) + return ret; + + /* Read bytes from shared buffer into the guest's destination. */ + if (exit_info_1 & IOIO_TYPE_IN) { + ret = vc_insn_string_write(ctxt, + (void *)(es_base + regs->di), + ghcb->shared_buffer, io_bytes, + exit_info_2, df); + if (ret) + return ret; + + if (df) + regs->di -= exit_bytes; + else + regs->di += exit_bytes; + } else { + if (df) + regs->si -= exit_bytes; + else + regs->si += exit_bytes; + } + + if (exit_info_1 & IOIO_REP) + regs->cx -= exit_info_2; + + ret = regs->cx ? ES_RETRY : ES_OK; + + } else { + + /* IN/OUT into/from rAX */ + + int bits = (exit_info_1 & 0x70) >> 1; + u64 rax = 0; + + if (!(exit_info_1 & IOIO_TYPE_IN)) + rax = lower_bits(regs->ax, bits); + + ghcb_set_rax(ghcb, rax); + + ret = sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_IOIO, exit_info_1, 0); + if (ret != ES_OK) + return ret; + + if (exit_info_1 & IOIO_TYPE_IN) { + if (!ghcb_is_valid_rax(ghcb)) + return ES_VMM_ERROR; + regs->ax = lower_bits(ghcb->save.rax, bits); + } + } + + return ret; +} From patchwork Tue Jul 14 12:08:27 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662633 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 1641214DD for ; Tue, 14 Jul 2020 12:16:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F04BC223C6 for ; Tue, 14 Jul 2020 12:16:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728448AbgGNMQK (ORCPT ); Tue, 14 Jul 2020 08:16:10 -0400 Received: from 8bytes.org ([81.169.241.247]:53376 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728262AbgGNMKu (ORCPT ); Tue, 14 Jul 2020 08:10:50 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 850F39B5; Tue, 14 Jul 2020 14:10:46 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 25/75] x86/fpu: Move xgetbv()/xsetbv() into separate header Date: Tue, 14 Jul 2020 14:08:27 +0200 Message-Id: <20200714120917.11253-26-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel The xgetbv() function is needed in pre-decompression boot code, but asm/fpu/internal.h can't be included there directly. Doing so opens the door to include-hell due to various include-magic in boot/compressed/misc.h. Avoid that by moving xgetbv()/xsetbv() to a separate header file and include this instead. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/fpu/internal.h | 33 +------------------------ arch/x86/include/asm/fpu/xcr.h | 37 +++++++++++++++++++++++++++++ 2 files changed, 38 insertions(+), 32 deletions(-) create mode 100644 arch/x86/include/asm/fpu/xcr.h diff --git a/arch/x86/include/asm/fpu/internal.h b/arch/x86/include/asm/fpu/internal.h index 845e7481ab77..1c724bbace04 100644 --- a/arch/x86/include/asm/fpu/internal.h +++ b/arch/x86/include/asm/fpu/internal.h @@ -19,6 +19,7 @@ #include #include #include +#include #include #include @@ -619,36 +620,4 @@ static inline void switch_fpu_finish(struct fpu *new_fpu) __write_pkru(pkru_val); } -/* - * MXCSR and XCR definitions: - */ - -static inline void ldmxcsr(u32 mxcsr) -{ - asm volatile("ldmxcsr %0" :: "m" (mxcsr)); -} - -extern unsigned int mxcsr_feature_mask; - -#define XCR_XFEATURE_ENABLED_MASK 0x00000000 - -static inline u64 xgetbv(u32 index) -{ - u32 eax, edx; - - asm volatile(".byte 0x0f,0x01,0xd0" /* xgetbv */ - : "=a" (eax), "=d" (edx) - : "c" (index)); - return eax + ((u64)edx << 32); -} - -static inline void xsetbv(u32 index, u64 value) -{ - u32 eax = value; - u32 edx = value >> 32; - - asm volatile(".byte 0x0f,0x01,0xd1" /* xsetbv */ - : : "a" (eax), "d" (edx), "c" (index)); -} - #endif /* _ASM_X86_FPU_INTERNAL_H */ diff --git a/arch/x86/include/asm/fpu/xcr.h b/arch/x86/include/asm/fpu/xcr.h new file mode 100644 index 000000000000..d8e8fafebfdc --- /dev/null +++ b/arch/x86/include/asm/fpu/xcr.h @@ -0,0 +1,37 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_X86_FPU_XCR_H +#define _ASM_X86_FPU_XCR_H + +/* + * MXCSR and XCR definitions: + */ + +static inline void ldmxcsr(u32 mxcsr) +{ + asm volatile("ldmxcsr %0" :: "m" (mxcsr)); +} + +extern unsigned int mxcsr_feature_mask; + +#define XCR_XFEATURE_ENABLED_MASK 0x00000000 + +static inline u64 xgetbv(u32 index) +{ + u32 eax, edx; + + asm volatile(".byte 0x0f,0x01,0xd0" /* xgetbv */ + : "=a" (eax), "=d" (edx) + : "c" (index)); + return eax + ((u64)edx << 32); +} + +static inline void xsetbv(u32 index, u64 value) +{ + u32 eax = value; + u32 edx = value >> 32; + + asm volatile(".byte 0x0f,0x01,0xd1" /* xsetbv */ + : : "a" (eax), "d" (edx), "c" (index)); +} + +#endif /* _ASM_X86_FPU_XCR_H */ From patchwork Tue Jul 14 12:08:28 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662531 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id F3F22618 for ; Tue, 14 Jul 2020 12:10:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E573F22261 for ; Tue, 14 Jul 2020 12:10:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728303AbgGNMKw (ORCPT ); Tue, 14 Jul 2020 08:10:52 -0400 Received: from 8bytes.org ([81.169.241.247]:52886 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728263AbgGNMKt (ORCPT ); Tue, 14 Jul 2020 08:10:49 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 10C829CE; Tue, 14 Jul 2020 14:10:47 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , Tom Lendacky , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 26/75] x86/sev-es: Add CPUID handling to #VC handler Date: Tue, 14 Jul 2020 14:08:28 +0200 Message-Id: <20200714120917.11253-27-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Tom Lendacky Handle #VC exceptions caused by CPUID instructions. These happen in early boot code when the KASLR code checks for RDTSC. Signed-off-by: Tom Lendacky [ jroedel@suse.de: Adapt to #VC handling framework ] Co-developed-by: Joerg Roedel Signed-off-by: Joerg Roedel --- arch/x86/boot/compressed/sev-es.c | 4 ++++ arch/x86/kernel/sev-es-shared.c | 35 +++++++++++++++++++++++++++++++ 2 files changed, 39 insertions(+) diff --git a/arch/x86/boot/compressed/sev-es.c b/arch/x86/boot/compressed/sev-es.c index 4f2fc7a85c2f..851d7af29d79 100644 --- a/arch/x86/boot/compressed/sev-es.c +++ b/arch/x86/boot/compressed/sev-es.c @@ -16,6 +16,7 @@ #include #include #include +#include #include #include @@ -183,6 +184,9 @@ void do_boot_stage2_vc(struct pt_regs *regs, unsigned long exit_code) case SVM_EXIT_IOIO: result = vc_handle_ioio(boot_ghcb, &ctxt); break; + case SVM_EXIT_CPUID: + result = vc_handle_cpuid(boot_ghcb, &ctxt); + break; default: result = ES_UNSUPPORTED; break; diff --git a/arch/x86/kernel/sev-es-shared.c b/arch/x86/kernel/sev-es-shared.c index 66d60e34eba0..59884926fae5 100644 --- a/arch/x86/kernel/sev-es-shared.c +++ b/arch/x86/kernel/sev-es-shared.c @@ -432,3 +432,38 @@ static enum es_result vc_handle_ioio(struct ghcb *ghcb, struct es_em_ctxt *ctxt) return ret; } + +static enum es_result vc_handle_cpuid(struct ghcb *ghcb, + struct es_em_ctxt *ctxt) +{ + struct pt_regs *regs = ctxt->regs; + u32 cr4 = native_read_cr4(); + enum es_result ret; + + ghcb_set_rax(ghcb, regs->ax); + ghcb_set_rcx(ghcb, regs->cx); + + if (cr4 & X86_CR4_OSXSAVE) + /* Safe to read xcr0 */ + ghcb_set_xcr0(ghcb, xgetbv(XCR_XFEATURE_ENABLED_MASK)); + else + /* xgetbv will cause #GP - use reset value for xcr0 */ + ghcb_set_xcr0(ghcb, 1); + + ret = sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_CPUID, 0, 0); + if (ret != ES_OK) + return ret; + + if (!(ghcb_is_valid_rax(ghcb) && + ghcb_is_valid_rbx(ghcb) && + ghcb_is_valid_rcx(ghcb) && + ghcb_is_valid_rdx(ghcb))) + return ES_VMM_ERROR; + + regs->ax = ghcb->save.rax; + regs->bx = ghcb->save.rbx; + regs->cx = ghcb->save.rcx; + regs->dx = ghcb->save.rdx; + + return ES_OK; +} From patchwork Tue Jul 14 12:08:29 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662629 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 490EE13B4 for ; Tue, 14 Jul 2020 12:16:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 32A7C223C6 for ; Tue, 14 Jul 2020 12:16:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728809AbgGNMQE (ORCPT ); Tue, 14 Jul 2020 08:16:04 -0400 Received: from 8bytes.org ([81.169.241.247]:53184 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728268AbgGNMKu (ORCPT ); Tue, 14 Jul 2020 08:10:50 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 9CA87B2D; Tue, 14 Jul 2020 14:10:47 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 27/75] x86/idt: Move IDT to data segment Date: Tue, 14 Jul 2020 14:08:29 +0200 Message-Id: <20200714120917.11253-28-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel With SEV-ES, exception handling is needed very early, even before the kernel has cleared the bss segment. In order to prevent clearing the currently used IDT, move the IDT to the data segment. Signed-off-by: Joerg Roedel Reviewed-by: Kees Cook --- arch/x86/kernel/idt.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kernel/idt.c b/arch/x86/kernel/idt.c index 0db21206f2f3..b920f2352df5 100644 --- a/arch/x86/kernel/idt.c +++ b/arch/x86/kernel/idt.c @@ -158,7 +158,7 @@ static const __initconst struct idt_data apic_idts[] = { }; /* Must be page-aligned because the real IDT is used in the cpu entry area */ -static gate_desc idt_table[IDT_ENTRIES] __page_aligned_bss; +static gate_desc idt_table[IDT_ENTRIES] __page_aligned_data; struct desc_ptr idt_descr __ro_after_init = { .size = IDT_TABLE_SIZE - 1, From patchwork Tue Jul 14 12:08:30 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662627 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id CA34013A4 for ; Tue, 14 Jul 2020 12:15:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B17B92242E for ; Tue, 14 Jul 2020 12:15:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728568AbgGNMP6 (ORCPT ); Tue, 14 Jul 2020 08:15:58 -0400 Received: from 8bytes.org ([81.169.241.247]:52918 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728284AbgGNMKv (ORCPT ); Tue, 14 Jul 2020 08:10:51 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 233E6B70; Tue, 14 Jul 2020 14:10:48 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 28/75] x86/idt: Split idt_data setup out of set_intr_gate() Date: Tue, 14 Jul 2020 14:08:30 +0200 Message-Id: <20200714120917.11253-29-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel The code to setup idt_data is needed for early exception handling, but set_intr_gate() can't be used that early because it has pv-ops in its code path, which don't work that early. Split out the idt_data initialization part from set_intr_gate() so that it can be used separatly. Signed-off-by: Joerg Roedel Reviewed-by: Kees Cook --- arch/x86/kernel/idt.c | 22 ++++++++++++++-------- 1 file changed, 14 insertions(+), 8 deletions(-) diff --git a/arch/x86/kernel/idt.c b/arch/x86/kernel/idt.c index b920f2352df5..367eb6a593dd 100644 --- a/arch/x86/kernel/idt.c +++ b/arch/x86/kernel/idt.c @@ -205,18 +205,24 @@ idt_setup_from_table(gate_desc *idt, const struct idt_data *t, int size, bool sy } } +static void init_idt_data(struct idt_data *data, unsigned int n, + const void *addr) +{ + BUG_ON(n > 0xFF); + + memset(data, 0, sizeof(*data)); + data->vector = n; + data->addr = addr; + data->segment = __KERNEL_CS; + data->bits.type = GATE_INTERRUPT; + data->bits.p = 1; +} + static __init void set_intr_gate(unsigned int n, const void *addr) { struct idt_data data; - BUG_ON(n > 0xFF); - - memset(&data, 0, sizeof(data)); - data.vector = n; - data.addr = addr; - data.segment = __KERNEL_CS; - data.bits.type = GATE_INTERRUPT; - data.bits.p = 1; + init_idt_data(&data, n, addr); idt_setup_from_table(idt_table, &data, 1, false); } From patchwork Tue Jul 14 12:08:31 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662625 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 113BB13A4 for ; Tue, 14 Jul 2020 12:15:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 01BB0223C6 for ; Tue, 14 Jul 2020 12:15:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728312AbgGNMPx (ORCPT ); Tue, 14 Jul 2020 08:15:53 -0400 Received: from 8bytes.org ([81.169.241.247]:52886 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728009AbgGNMKv (ORCPT ); Tue, 14 Jul 2020 08:10:51 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 9C076C07; Tue, 14 Jul 2020 14:10:48 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 29/75] x86/idt: Move two function from k/idt.c to i/a/desc.h Date: Tue, 14 Jul 2020 14:08:31 +0200 Message-Id: <20200714120917.11253-30-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Move these two functions from kernel/idt.c to include/asm/desc.h: * init_idt_data() * idt_init_desc() These functions are needed to setup IDT entries very early and need to be called from head64.c. To be usable this early these functions need to be compiled without instrumentation and the stack-protector feature. These features need to be kept enabled for kernel/idt.c, so head64.c must use its own versions. Signed-off-by: Joerg Roedel Reviewed-by: Kees Cook --- arch/x86/include/asm/desc.h | 27 +++++++++++++++++++++++++ arch/x86/include/asm/desc_defs.h | 7 +++++++ arch/x86/kernel/idt.c | 34 -------------------------------- 3 files changed, 34 insertions(+), 34 deletions(-) diff --git a/arch/x86/include/asm/desc.h b/arch/x86/include/asm/desc.h index 1ced11d31932..476082a83d1c 100644 --- a/arch/x86/include/asm/desc.h +++ b/arch/x86/include/asm/desc.h @@ -383,6 +383,33 @@ static inline void set_desc_limit(struct desc_struct *desc, unsigned long limit) void alloc_intr_gate(unsigned int n, const void *addr); +static inline void init_idt_data(struct idt_data *data, unsigned int n, + const void *addr) +{ + BUG_ON(n > 0xFF); + + memset(data, 0, sizeof(*data)); + data->vector = n; + data->addr = addr; + data->segment = __KERNEL_CS; + data->bits.type = GATE_INTERRUPT; + data->bits.p = 1; +} + +static inline void idt_init_desc(gate_desc *gate, const struct idt_data *d) +{ + unsigned long addr = (unsigned long) d->addr; + + gate->offset_low = (u16) addr; + gate->segment = (u16) d->segment; + gate->bits = d->bits; + gate->offset_middle = (u16) (addr >> 16); +#ifdef CONFIG_X86_64 + gate->offset_high = (u32) (addr >> 32); + gate->reserved = 0; +#endif +} + extern unsigned long system_vectors[]; extern void load_current_idt(void); diff --git a/arch/x86/include/asm/desc_defs.h b/arch/x86/include/asm/desc_defs.h index 5621fb3f2d1a..f7e7099af595 100644 --- a/arch/x86/include/asm/desc_defs.h +++ b/arch/x86/include/asm/desc_defs.h @@ -74,6 +74,13 @@ struct idt_bits { p : 1; } __attribute__((packed)); +struct idt_data { + unsigned int vector; + unsigned int segment; + struct idt_bits bits; + const void *addr; +}; + struct gate_struct { u16 offset_low; u16 segment; diff --git a/arch/x86/kernel/idt.c b/arch/x86/kernel/idt.c index 367eb6a593dd..d3f0c8133300 100644 --- a/arch/x86/kernel/idt.c +++ b/arch/x86/kernel/idt.c @@ -11,13 +11,6 @@ #include #include -struct idt_data { - unsigned int vector; - unsigned int segment; - struct idt_bits bits; - const void *addr; -}; - #define DPL0 0x0 #define DPL3 0x3 @@ -178,20 +171,6 @@ bool idt_is_f00f_address(unsigned long address) } #endif -static inline void idt_init_desc(gate_desc *gate, const struct idt_data *d) -{ - unsigned long addr = (unsigned long) d->addr; - - gate->offset_low = (u16) addr; - gate->segment = (u16) d->segment; - gate->bits = d->bits; - gate->offset_middle = (u16) (addr >> 16); -#ifdef CONFIG_X86_64 - gate->offset_high = (u32) (addr >> 32); - gate->reserved = 0; -#endif -} - static __init void idt_setup_from_table(gate_desc *idt, const struct idt_data *t, int size, bool sys) { @@ -205,19 +184,6 @@ idt_setup_from_table(gate_desc *idt, const struct idt_data *t, int size, bool sy } } -static void init_idt_data(struct idt_data *data, unsigned int n, - const void *addr) -{ - BUG_ON(n > 0xFF); - - memset(data, 0, sizeof(*data)); - data->vector = n; - data->addr = addr; - data->segment = __KERNEL_CS; - data->bits.type = GATE_INTERRUPT; - data->bits.p = 1; -} - static __init void set_intr_gate(unsigned int n, const void *addr) { struct idt_data data; From patchwork Tue Jul 14 12:08:32 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662619 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 30AE213A4 for ; Tue, 14 Jul 2020 12:15:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 215642068F for ; Tue, 14 Jul 2020 12:15:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728927AbgGNMP3 (ORCPT ); Tue, 14 Jul 2020 08:15:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60650 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728308AbgGNMKx (ORCPT ); Tue, 14 Jul 2020 08:10:53 -0400 Received: from theia.8bytes.org (8bytes.org [IPv6:2a01:238:4383:600:38bc:a715:4b6d:a889]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CC079C061755; Tue, 14 Jul 2020 05:10:52 -0700 (PDT) Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 2398AF19; Tue, 14 Jul 2020 14:10:49 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 30/75] x86/head/64: Install boot GDT Date: Tue, 14 Jul 2020 14:08:32 +0200 Message-Id: <20200714120917.11253-31-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Handling exceptions during boot requires a working GDT. The kernel GDT is not yet ready for use, so install a temporary boot GDT. Signed-off-by: Joerg Roedel --- arch/x86/kernel/head64.c | 19 +++++++++++++++++++ arch/x86/kernel/head_64.S | 20 ++++++++++++++++++++ 2 files changed, 39 insertions(+) diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index cbb71c1b574f..51059bfd4b99 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -61,6 +61,25 @@ unsigned long vmemmap_base __ro_after_init = __VMEMMAP_BASE_L4; EXPORT_SYMBOL(vmemmap_base); #endif +/* + * GDT used before %gs is set up and the kernel can use gdt_page. Needed for + * early exception handling. + */ +struct desc_struct boot_gdt[GDT_ENTRIES] = { + [GDT_ENTRY_KERNEL32_CS] = GDT_ENTRY_INIT(0xc09b, 0, 0xfffff), + [GDT_ENTRY_KERNEL_CS] = GDT_ENTRY_INIT(0xa09b, 0, 0xfffff), + [GDT_ENTRY_KERNEL_DS] = GDT_ENTRY_INIT(0xc093, 0, 0xfffff), +}; + +/* + * Address needs to be set at runtime because it references the boot_gdt while + * the kernel still uses a direct mapping. + */ +struct desc_ptr boot_gdt_descr = { + .size = sizeof(boot_gdt), + .address = 0, +}; + #define __head __section(.head.text) static void __head *fixup_pointer(void *ptr, unsigned long physaddr) diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 16da4ac01597..473e60a12e2f 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -73,6 +73,26 @@ SYM_CODE_START_NOALIGN(startup_64) /* Set up the stack for verify_cpu(), similar to initial_stack below */ leaq (__end_init_task - SIZEOF_PTREGS)(%rip), %rsp + /* Setup boot GDT descriptor and load boot GDT */ + leaq boot_gdt(%rip), %rax + movq %rax, boot_gdt_descr+2(%rip) + lgdt boot_gdt_descr(%rip) + + /* New GDT is live - reload data segment registers */ + movl $__KERNEL_DS, %eax + movl %eax, %ds + movl %eax, %ss + movl %eax, %es + + /* Now switch to __KERNEL_CS so IRET works reliably */ + pushq $__KERNEL_CS + leaq .Lon_kernel_cs(%rip), %rax + pushq %rax + lretq + +.Lon_kernel_cs: + UNWIND_HINT_EMPTY + /* Sanitize CPU configuration */ call verify_cpu From patchwork Tue Jul 14 12:08:33 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662533 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 28FC9618 for ; Tue, 14 Jul 2020 12:10:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1B66322274 for ; Tue, 14 Jul 2020 12:10:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728318AbgGNMKx (ORCPT ); Tue, 14 Jul 2020 08:10:53 -0400 Received: from 8bytes.org ([81.169.241.247]:53376 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728298AbgGNMKw (ORCPT ); Tue, 14 Jul 2020 08:10:52 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id A10D1D16; Tue, 14 Jul 2020 14:10:49 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 31/75] x86/head/64: Reload GDT after switch to virtual addresses Date: Tue, 14 Jul 2020 14:08:33 +0200 Message-Id: <20200714120917.11253-32-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Reload the GDT after switching to virtual addresses to make sure it will not go away when the lower mappings are removed. This will also reload the GDT for booting APs, which will need a working GDT too to handle #VC exceptions. Signed-off-by: Joerg Roedel --- arch/x86/kernel/head_64.S | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 473e60a12e2f..87ea9f540608 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -164,6 +164,11 @@ SYM_CODE_START(secondary_startup_64) 1: UNWIND_HINT_EMPTY + /* Setup boot GDT descriptor and load boot GDT */ + leaq boot_gdt(%rip), %rax + movq %rax, boot_gdt_descr+2(%rip) + lgdt boot_gdt_descr(%rip) + /* Check if nx is implemented */ movl $0x80000001, %eax cpuid From patchwork Tue Jul 14 12:08:34 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662621 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 1531E13A4 for ; Tue, 14 Jul 2020 12:15:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 07B8522370 for ; Tue, 14 Jul 2020 12:15:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728936AbgGNMPa (ORCPT ); Tue, 14 Jul 2020 08:15:30 -0400 Received: from 8bytes.org ([81.169.241.247]:52918 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728304AbgGNMKx (ORCPT ); Tue, 14 Jul 2020 08:10:53 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 25E2EE1F; Tue, 14 Jul 2020 14:10:50 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 32/75] x86/head/64: Load segment registers earlier Date: Tue, 14 Jul 2020 14:08:34 +0200 Message-Id: <20200714120917.11253-33-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Make sure segments are properly set up before setting up an IDT and doing anything that might cause a #VC exception. This is later needed for early exception handling. Signed-off-by: Joerg Roedel --- arch/x86/kernel/head_64.S | 52 +++++++++++++++++++-------------------- 1 file changed, 26 insertions(+), 26 deletions(-) diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 87ea9f540608..61aa1e56fc9c 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -169,6 +169,32 @@ SYM_CODE_START(secondary_startup_64) movq %rax, boot_gdt_descr+2(%rip) lgdt boot_gdt_descr(%rip) + /* set up data segments */ + xorl %eax,%eax + movl %eax,%ds + movl %eax,%ss + movl %eax,%es + + /* + * We don't really need to load %fs or %gs, but load them anyway + * to kill any stale realmode selectors. This allows execution + * under VT hardware. + */ + movl %eax,%fs + movl %eax,%gs + + /* Set up %gs. + * + * The base of %gs always points to fixed_percpu_data. If the + * stack protector canary is enabled, it is located at %gs:40. + * Note that, on SMP, the boot cpu uses init data section until + * the per cpu areas are set up. + */ + movl $MSR_GS_BASE,%ecx + movl initial_gs(%rip),%eax + movl initial_gs+4(%rip),%edx + wrmsr + /* Check if nx is implemented */ movl $0x80000001, %eax cpuid @@ -204,32 +230,6 @@ SYM_CODE_START(secondary_startup_64) */ lgdt early_gdt_descr(%rip) - /* set up data segments */ - xorl %eax,%eax - movl %eax,%ds - movl %eax,%ss - movl %eax,%es - - /* - * We don't really need to load %fs or %gs, but load them anyway - * to kill any stale realmode selectors. This allows execution - * under VT hardware. - */ - movl %eax,%fs - movl %eax,%gs - - /* Set up %gs. - * - * The base of %gs always points to fixed_percpu_data. If the - * stack protector canary is enabled, it is located at %gs:40. - * Note that, on SMP, the boot cpu uses init data section until - * the per cpu areas are set up. - */ - movl $MSR_GS_BASE,%ecx - movl initial_gs(%rip),%eax - movl initial_gs+4(%rip),%edx - wrmsr - /* rsi is pointer to real mode structure with interesting info. pass it to C */ movq %rsi, %rdi From patchwork Tue Jul 14 12:08:35 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662617 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C892213A4 for ; Tue, 14 Jul 2020 12:15:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AF6402067D for ; Tue, 14 Jul 2020 12:15:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728919AbgGNMP1 (ORCPT ); Tue, 14 Jul 2020 08:15:27 -0400 Received: from 8bytes.org ([81.169.241.247]:52886 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728305AbgGNMKx (ORCPT ); Tue, 14 Jul 2020 08:10:53 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id B421AE6C; Tue, 14 Jul 2020 14:10:50 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 33/75] x86/head/64: Switch to initial stack earlier Date: Tue, 14 Jul 2020 14:08:35 +0200 Message-Id: <20200714120917.11253-34-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Make sure there is a stack once the kernel runs from virual addresses. At this stage any secondary CPU which boots will have lost its stack because the kernel switched to a new page-table which does not map the real-mode stack anymore. This is needed for handling early #VC exceptions caused by instructions like CPUID. Signed-off-by: Joerg Roedel --- arch/x86/kernel/head_64.S | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 61aa1e56fc9c..fcaa5dbd728a 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -195,6 +195,12 @@ SYM_CODE_START(secondary_startup_64) movl initial_gs+4(%rip),%edx wrmsr + /* + * Setup a boot time stack - Any secondary CPU will have lost its stack + * by now because the cr3-switch above unmaps the real-mode stack + */ + movq initial_stack(%rip), %rsp + /* Check if nx is implemented */ movl $0x80000001, %eax cpuid @@ -215,9 +221,6 @@ SYM_CODE_START(secondary_startup_64) /* Make changes effective */ movq %rax, %cr0 - /* Setup a boot time stack */ - movq initial_stack(%rip), %rsp - /* zero EFLAGS after setting rsp */ pushq $0 popfq From patchwork Tue Jul 14 12:08:36 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662623 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 1044D13A4 for ; Tue, 14 Jul 2020 12:15:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 000BE223C6 for ; Tue, 14 Jul 2020 12:15:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728674AbgGNMP0 (ORCPT ); Tue, 14 Jul 2020 08:15:26 -0400 Received: from 8bytes.org ([81.169.241.247]:53376 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728310AbgGNMKx (ORCPT ); Tue, 14 Jul 2020 08:10:53 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 470F0E6D; Tue, 14 Jul 2020 14:10:51 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 34/75] x86/head/64: Build k/head64.c with -fno-stack-protector Date: Tue, 14 Jul 2020 14:08:36 +0200 Message-Id: <20200714120917.11253-35-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel The code inserted by the stack protector does not work in the early boot environment because it uses the GS segment, at least with memory encryption enabled. Make sure the early code is compiled without this feature enabled. Signed-off-by: Joerg Roedel Reviewed-by: Kees Cook --- arch/x86/kernel/Makefile | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index e77261db2391..1b166b866059 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -39,6 +39,10 @@ ifdef CONFIG_FRAME_POINTER OBJECT_FILES_NON_STANDARD_ftrace_$(BITS).o := y endif +# make sure head64.c is built without stack protector +nostackp := $(call cc-option, -fno-stack-protector) +CFLAGS_head64.o := $(nostackp) + # If instrumentation of this dir is enabled, boot hangs during first second. # Probably could be more selective here, but note that files related to irqs, # boot, dumpstack/stacktrace, etc are either non-interesting or can lead to From patchwork Tue Jul 14 12:08:37 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662613 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id AAE7013B4 for ; Tue, 14 Jul 2020 12:15:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9D40E20657 for ; Tue, 14 Jul 2020 12:15:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728740AbgGNMPM (ORCPT ); Tue, 14 Jul 2020 08:15:12 -0400 Received: from 8bytes.org ([81.169.241.247]:53652 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728324AbgGNMKz (ORCPT ); Tue, 14 Jul 2020 08:10:55 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id CB707F3C; Tue, 14 Jul 2020 14:10:51 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 35/75] x86/head/64: Load IDT earlier Date: Tue, 14 Jul 2020 14:08:37 +0200 Message-Id: <20200714120917.11253-36-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Load the IDT right after switching to virtual addresses in head_64.S so that the kernel can handle #VC exceptions. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/setup.h | 2 ++ arch/x86/kernel/head64.c | 18 ++++++++++++++++++ arch/x86/kernel/head_64.S | 28 ++++++++++++++++++++++++++++ 3 files changed, 48 insertions(+) diff --git a/arch/x86/include/asm/setup.h b/arch/x86/include/asm/setup.h index 84b645cc8bc9..19ccb1211004 100644 --- a/arch/x86/include/asm/setup.h +++ b/arch/x86/include/asm/setup.h @@ -39,6 +39,7 @@ void vsmp_init(void); static inline void vsmp_init(void) { } #endif + void setup_bios_corruption_check(void); void early_platform_quirks(void); @@ -49,6 +50,7 @@ extern void i386_reserve_resources(void); extern unsigned long __startup_64(unsigned long physaddr, struct boot_params *bp); extern unsigned long __startup_secondary_64(void); extern int early_make_pgtable(unsigned long address); +extern void early_idt_setup_early_handler(unsigned long descr_addr, unsigned long physaddr); #ifdef CONFIG_X86_INTEL_MID extern void x86_intel_mid_early_setup(void); diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index 51059bfd4b99..3598c091ff24 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -508,3 +508,21 @@ void __init x86_64_start_reservations(char *real_mode_data) start_kernel(); } + +void __head early_idt_setup_early_handler(unsigned long descr_addr, unsigned long physaddr) +{ + struct desc_ptr *descr = (struct desc_ptr *)descr_addr; + gate_desc *idt = (gate_desc *)descr->address; + int i; + + idt = fixup_pointer(idt, physaddr); + + for (i = 0; i < NUM_EXCEPTION_VECTORS; i++) { + struct idt_data data; + gate_desc desc; + + init_idt_data(&data, i, early_idt_handler_array[i]); + idt_init_desc(&desc, &data); + native_write_idt_entry(idt, i, &desc); + } +} diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index fcaa5dbd728a..8f9548071e84 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -105,6 +105,31 @@ SYM_CODE_START_NOALIGN(startup_64) leaq _text(%rip), %rdi pushq %rsi call __startup_64 + /* Save return value */ + pushq %rax + + /* + * Load IDT with early handlers - needed for SEV-ES + * Do this here because this must only happen on the boot CPU + * and the code below is shared with secondary CPU bringup. + */ + + /* IDT descriptor with pointer to IDT table as first parameter */ + leaq idt_descr(%rip), %rdi + + /* Kernel _text offset as second parameter */ + leaq _text(%rip), %rsi + + /* + * Setup IDT with early entries - The entries already use virtual + * addresses, so the IDT can't be used until the kernel switched to + * virtual addresses too. + */ + call early_idt_setup_early_handler + + /* Restore __startup_64 return value*/ + popq %rax + /* Restore pointer to real_mode_data */ popq %rsi /* Form the CR3 value being sure to include the CR3 modifier */ @@ -201,6 +226,9 @@ SYM_CODE_START(secondary_startup_64) */ movq initial_stack(%rip), %rsp + /* Load IDT */ + lidt idt_descr(%rip) + /* Check if nx is implemented */ movl $0x80000001, %eax cpuid From patchwork Tue Jul 14 12:08:38 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662615 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 823C813B4 for ; Tue, 14 Jul 2020 12:15:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 742F720657 for ; Tue, 14 Jul 2020 12:15:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728576AbgGNMPM (ORCPT ); Tue, 14 Jul 2020 08:15:12 -0400 Received: from 8bytes.org ([81.169.241.247]:53684 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728335AbgGNMK4 (ORCPT ); Tue, 14 Jul 2020 08:10:56 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 5BFB8F5C; Tue, 14 Jul 2020 14:10:52 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 36/75] x86/head/64: Move early exception dispatch to C code Date: Tue, 14 Jul 2020 14:08:38 +0200 Message-Id: <20200714120917.11253-37-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Move the assembly coded dispatch between page-faults and all other exceptions to C code to make it easier to maintain and extend. Also change the return-type of early_make_pgtable() to bool and make it static. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/pgtable.h | 2 +- arch/x86/include/asm/setup.h | 1 - arch/x86/kernel/head64.c | 19 +++++++++++++++---- arch/x86/kernel/head_64.S | 11 +---------- 4 files changed, 17 insertions(+), 16 deletions(-) diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h index 76aa21e8128d..001b719a5e29 100644 --- a/arch/x86/include/asm/pgtable.h +++ b/arch/x86/include/asm/pgtable.h @@ -28,7 +28,7 @@ #include extern pgd_t early_top_pgt[PTRS_PER_PGD]; -int __init __early_make_pgtable(unsigned long address, pmdval_t pmd); +bool __init __early_make_pgtable(unsigned long address, pmdval_t pmd); void ptdump_walk_pgd_level(struct seq_file *m, struct mm_struct *mm); void ptdump_walk_pgd_level_debugfs(struct seq_file *m, struct mm_struct *mm, diff --git a/arch/x86/include/asm/setup.h b/arch/x86/include/asm/setup.h index 19ccb1211004..5b3a9883ecc7 100644 --- a/arch/x86/include/asm/setup.h +++ b/arch/x86/include/asm/setup.h @@ -49,7 +49,6 @@ extern void reserve_standard_io_resources(void); extern void i386_reserve_resources(void); extern unsigned long __startup_64(unsigned long physaddr, struct boot_params *bp); extern unsigned long __startup_secondary_64(void); -extern int early_make_pgtable(unsigned long address); extern void early_idt_setup_early_handler(unsigned long descr_addr, unsigned long physaddr); #ifdef CONFIG_X86_INTEL_MID diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index 3598c091ff24..32080e34ba92 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -36,6 +36,8 @@ #include #include #include +#include +#include /* * Manage page tables very early on. @@ -316,7 +318,7 @@ static void __init reset_early_page_tables(void) } /* Create a new PMD entry */ -int __init __early_make_pgtable(unsigned long address, pmdval_t pmd) +bool __init __early_make_pgtable(unsigned long address, pmdval_t pmd) { unsigned long physaddr = address - __PAGE_OFFSET; pgdval_t pgd, *pgd_p; @@ -326,7 +328,7 @@ int __init __early_make_pgtable(unsigned long address, pmdval_t pmd) /* Invalid address or early pgt is done ? */ if (physaddr >= MAXMEM || read_cr3_pa() != __pa_nodebug(early_top_pgt)) - return -1; + return false; again: pgd_p = &early_top_pgt[pgd_index(address)].pgd; @@ -383,10 +385,10 @@ int __init __early_make_pgtable(unsigned long address, pmdval_t pmd) } pmd_p[pmd_index(address)] = pmd; - return 0; + return true; } -int __init early_make_pgtable(unsigned long address) +static bool __init early_make_pgtable(unsigned long address) { unsigned long physaddr = address - __PAGE_OFFSET; pmdval_t pmd; @@ -396,6 +398,15 @@ int __init early_make_pgtable(unsigned long address) return __early_make_pgtable(address, pmd); } +void __init do_early_exception(struct pt_regs *regs, int trapnr) +{ + if (trapnr == X86_TRAP_PF && + early_make_pgtable(native_read_cr2())) + return; + + early_fixup_exception(regs, trapnr); +} + /* Don't add a printk in there. printk relies on the PDA which is not initialized yet. */ static void __init clear_bss(void) diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 8f9548071e84..86473d49619d 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -375,18 +375,9 @@ SYM_CODE_START_LOCAL(early_idt_handler_common) pushq %r15 /* pt_regs->r15 */ UNWIND_HINT_REGS - cmpq $14,%rsi /* Page fault? */ - jnz 10f - GET_CR2_INTO(%rdi) /* can clobber %rax if pv */ - call early_make_pgtable - andl %eax,%eax - jz 20f /* All good */ - -10: movq %rsp,%rdi /* RDI = pt_regs; RSI is already trapnr */ - call early_fixup_exception + call do_early_exception -20: decl early_recursion_flag(%rip) jmp restore_regs_and_return_to_kernel SYM_CODE_END(early_idt_handler_common) From patchwork Tue Jul 14 12:08:39 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662609 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 860E213B4 for ; Tue, 14 Jul 2020 12:14:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 77C3B223C6 for ; Tue, 14 Jul 2020 12:14:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728655AbgGNMO4 (ORCPT ); Tue, 14 Jul 2020 08:14:56 -0400 Received: from 8bytes.org ([81.169.241.247]:53718 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728337AbgGNMK5 (ORCPT ); Tue, 14 Jul 2020 08:10:57 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 0B113F6F; Tue, 14 Jul 2020 14:10:52 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 37/75] x86/sev-es: Add SEV-ES Feature Detection Date: Tue, 14 Jul 2020 14:08:39 +0200 Message-Id: <20200714120917.11253-38-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Add the sev_es_active function for checking whether SEV-ES is enabled. Also cache the value of MSR_AMD64_SEV at boot to speed up the feature checking in the running code. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/mem_encrypt.h | 3 +++ arch/x86/include/asm/msr-index.h | 2 ++ arch/x86/mm/mem_encrypt.c | 9 ++++++++- arch/x86/mm/mem_encrypt_identity.c | 3 +++ 4 files changed, 16 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/mem_encrypt.h b/arch/x86/include/asm/mem_encrypt.h index 848ce43b9040..6f61bb93366a 100644 --- a/arch/x86/include/asm/mem_encrypt.h +++ b/arch/x86/include/asm/mem_encrypt.h @@ -19,6 +19,7 @@ #ifdef CONFIG_AMD_MEM_ENCRYPT extern u64 sme_me_mask; +extern u64 sev_status; extern bool sev_enabled; void sme_encrypt_execute(unsigned long encrypted_kernel_vaddr, @@ -49,6 +50,7 @@ void __init mem_encrypt_free_decrypted_mem(void); bool sme_active(void); bool sev_active(void); +bool sev_es_active(void); #define __bss_decrypted __attribute__((__section__(".bss..decrypted"))) @@ -71,6 +73,7 @@ static inline void __init sme_enable(struct boot_params *bp) { } static inline bool sme_active(void) { return false; } static inline bool sev_active(void) { return false; } +static inline bool sev_es_active(void) { return false; } static inline int __init early_set_memory_decrypted(unsigned long vaddr, unsigned long size) { return 0; } diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h index 2816eb01463f..cac329037777 100644 --- a/arch/x86/include/asm/msr-index.h +++ b/arch/x86/include/asm/msr-index.h @@ -451,7 +451,9 @@ #define MSR_AMD64_SEV_ES_GHCB 0xc0010130 #define MSR_AMD64_SEV 0xc0010131 #define MSR_AMD64_SEV_ENABLED_BIT 0 +#define MSR_AMD64_SEV_ES_ENABLED_BIT 1 #define MSR_AMD64_SEV_ENABLED BIT_ULL(MSR_AMD64_SEV_ENABLED_BIT) +#define MSR_AMD64_SEV_ES_ENABLED BIT_ULL(MSR_AMD64_SEV_ES_ENABLED_BIT) #define MSR_AMD64_VIRT_SPEC_CTRL 0xc001011f diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c index 4a781cf99e92..21be138ceef6 100644 --- a/arch/x86/mm/mem_encrypt.c +++ b/arch/x86/mm/mem_encrypt.c @@ -38,6 +38,7 @@ * section is later cleared. */ u64 sme_me_mask __section(.data) = 0; +u64 sev_status __section(.data) = 0; EXPORT_SYMBOL(sme_me_mask); DEFINE_STATIC_KEY_FALSE(sev_enable_key); EXPORT_SYMBOL_GPL(sev_enable_key); @@ -347,7 +348,13 @@ bool sme_active(void) bool sev_active(void) { - return sme_me_mask && sev_enabled; + return !!(sev_status & MSR_AMD64_SEV_ENABLED); +} + +/* Needs to be called from non-instrumentable code */ +bool noinstr sev_es_active(void) +{ + return !!(sev_status & MSR_AMD64_SEV_ES_ENABLED); } /* Override for DMA direct allocation check - ARCH_HAS_FORCE_DMA_UNENCRYPTED */ diff --git a/arch/x86/mm/mem_encrypt_identity.c b/arch/x86/mm/mem_encrypt_identity.c index e2b0e2ac07bb..68d75379e06a 100644 --- a/arch/x86/mm/mem_encrypt_identity.c +++ b/arch/x86/mm/mem_encrypt_identity.c @@ -540,6 +540,9 @@ void __init sme_enable(struct boot_params *bp) if (!(msr & MSR_AMD64_SEV_ENABLED)) return; + /* Save SEV_STATUS to avoid reading MSR again */ + sev_status = msr; + /* SEV state cannot be controlled by a command line option */ sme_me_mask = me_mask; sev_enabled = true; From patchwork Tue Jul 14 12:08:40 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662607 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 2E07C618 for ; Tue, 14 Jul 2020 12:14:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1FEDA223C6 for ; Tue, 14 Jul 2020 12:14:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728364AbgGNMOq (ORCPT ); Tue, 14 Jul 2020 08:14:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60676 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728379AbgGNMK7 (ORCPT ); Tue, 14 Jul 2020 08:10:59 -0400 Received: from theia.8bytes.org (8bytes.org [IPv6:2a01:238:4383:600:38bc:a715:4b6d:a889]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F27C4C061794; Tue, 14 Jul 2020 05:10:58 -0700 (PDT) Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 9AE08F78; Tue, 14 Jul 2020 14:10:53 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 38/75] x86/sev-es: Print SEV-ES info into kernel log Date: Tue, 14 Jul 2020 14:08:40 +0200 Message-Id: <20200714120917.11253-39-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Refactor the message printed to the kernel log which indicates whether SEV or SME is active to print a list of enabled encryption features. This will scale better in the future when more memory encryption features might be added. Also add SEV-ES to the list of features. Signed-off-by: Joerg Roedel --- arch/x86/mm/mem_encrypt.c | 29 ++++++++++++++++++++++++++--- 1 file changed, 26 insertions(+), 3 deletions(-) diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c index 21be138ceef6..cbf7935c873b 100644 --- a/arch/x86/mm/mem_encrypt.c +++ b/arch/x86/mm/mem_encrypt.c @@ -408,6 +408,31 @@ void __init mem_encrypt_free_decrypted_mem(void) free_init_pages("unused decrypted", vaddr, vaddr_end); } +static void print_mem_encrypt_feature_info(void) +{ + pr_info("AMD Memory Encryption Features active:"); + + /* Secure Memory Encryption */ + if (sme_active()) { + /* + * SME is mutually exclusive with any of the SEV + * features below. + */ + pr_cont(" SME\n"); + return; + } + + /* Secure Encrypted Virtualization */ + if (sev_active()) + pr_cont(" SEV"); + + /* Encrypted Register State */ + if (sev_es_active()) + pr_cont(" SEV-ES"); + + pr_cont("\n"); +} + void __init mem_encrypt_init(void) { if (!sme_me_mask) @@ -422,8 +447,6 @@ void __init mem_encrypt_init(void) if (sev_active()) static_branch_enable(&sev_enable_key); - pr_info("AMD %s active\n", - sev_active() ? "Secure Encrypted Virtualization (SEV)" - : "Secure Memory Encryption (SME)"); + print_mem_encrypt_feature_info(); } From patchwork Tue Jul 14 12:08:41 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662603 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 659FD618 for ; Tue, 14 Jul 2020 12:14:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 515882236F for ; Tue, 14 Jul 2020 12:14:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728368AbgGNMOd (ORCPT ); Tue, 14 Jul 2020 08:14:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60682 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728387AbgGNMK7 (ORCPT ); Tue, 14 Jul 2020 08:10:59 -0400 Received: from theia.8bytes.org (8bytes.org [IPv6:2a01:238:4383:600:38bc:a715:4b6d:a889]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7C798C08C5C1; Tue, 14 Jul 2020 05:10:59 -0700 (PDT) Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 33F53F87; Tue, 14 Jul 2020 14:10:54 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 39/75] x86/sev-es: Compile early handler code into kernel image Date: Tue, 14 Jul 2020 14:08:41 +0200 Message-Id: <20200714120917.11253-40-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Setup sev-es.c and include the code from the pre-decompression stage to also build it into the image of the running kernel. Temporarily add __maybe_unused annotations to avoid build warnings until the functions get used. Signed-off-by: Joerg Roedel --- arch/x86/kernel/Makefile | 1 + arch/x86/kernel/sev-es-shared.c | 21 ++-- arch/x86/kernel/sev-es.c | 163 ++++++++++++++++++++++++++++++++ 3 files changed, 175 insertions(+), 10 deletions(-) create mode 100644 arch/x86/kernel/sev-es.c diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index 1b166b866059..81276033a80e 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -149,6 +149,7 @@ obj-$(CONFIG_UNWINDER_ORC) += unwind_orc.o obj-$(CONFIG_UNWINDER_FRAME_POINTER) += unwind_frame.o obj-$(CONFIG_UNWINDER_GUESS) += unwind_guess.o +obj-$(CONFIG_AMD_MEM_ENCRYPT) += sev-es.o ### # 64 bit specific files ifeq ($(CONFIG_X86_64),y) diff --git a/arch/x86/kernel/sev-es-shared.c b/arch/x86/kernel/sev-es-shared.c index 59884926fae5..df6750aef3c8 100644 --- a/arch/x86/kernel/sev-es-shared.c +++ b/arch/x86/kernel/sev-es-shared.c @@ -9,7 +9,7 @@ * and is included directly into both code-bases. */ -static void sev_es_terminate(unsigned int reason) +static void __maybe_unused sev_es_terminate(unsigned int reason) { u64 val = GHCB_SEV_TERMINATE; @@ -27,7 +27,7 @@ static void sev_es_terminate(unsigned int reason) asm volatile("hlt\n" : : : "memory"); } -static bool sev_es_negotiate_protocol(void) +static bool __maybe_unused sev_es_negotiate_protocol(void) { u64 val; @@ -46,7 +46,7 @@ static bool sev_es_negotiate_protocol(void) return true; } -static void vc_ghcb_invalidate(struct ghcb *ghcb) +static void __maybe_unused vc_ghcb_invalidate(struct ghcb *ghcb) { memset(ghcb->save.valid_bitmap, 0, sizeof(ghcb->save.valid_bitmap)); } @@ -58,9 +58,9 @@ static bool vc_decoding_needed(unsigned long exit_code) exit_code <= SVM_EXIT_LAST_EXCP); } -static enum es_result vc_init_em_ctxt(struct es_em_ctxt *ctxt, - struct pt_regs *regs, - unsigned long exit_code) +static enum es_result __maybe_unused vc_init_em_ctxt(struct es_em_ctxt *ctxt, + struct pt_regs *regs, + unsigned long exit_code) { enum es_result ret = ES_OK; @@ -73,7 +73,7 @@ static enum es_result vc_init_em_ctxt(struct es_em_ctxt *ctxt, return ret; } -static void vc_finish_insn(struct es_em_ctxt *ctxt) +static void __maybe_unused vc_finish_insn(struct es_em_ctxt *ctxt) { ctxt->regs->ip += ctxt->insn.length; } @@ -325,7 +325,8 @@ static enum es_result vc_ioio_exitinfo(struct es_em_ctxt *ctxt, u64 *exitinfo) return ES_OK; } -static enum es_result vc_handle_ioio(struct ghcb *ghcb, struct es_em_ctxt *ctxt) +static enum es_result __maybe_unused +vc_handle_ioio(struct ghcb *ghcb, struct es_em_ctxt *ctxt) { struct pt_regs *regs = ctxt->regs; u64 exit_info_1, exit_info_2; @@ -433,8 +434,8 @@ static enum es_result vc_handle_ioio(struct ghcb *ghcb, struct es_em_ctxt *ctxt) return ret; } -static enum es_result vc_handle_cpuid(struct ghcb *ghcb, - struct es_em_ctxt *ctxt) +static enum es_result __maybe_unused vc_handle_cpuid(struct ghcb *ghcb, + struct es_em_ctxt *ctxt) { struct pt_regs *regs = ctxt->regs; u32 cr4 = native_read_cr4(); diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c new file mode 100644 index 000000000000..0b698b653c0b --- /dev/null +++ b/arch/x86/kernel/sev-es.c @@ -0,0 +1,163 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * AMD Memory Encryption Support + * + * Copyright (C) 2019 SUSE + * + * Author: Joerg Roedel + */ + +#include +#include + +#include +#include +#include +#include +#include +#include +#include + +static inline u64 sev_es_rd_ghcb_msr(void) +{ + return native_read_msr(MSR_AMD64_SEV_ES_GHCB); +} + +static inline void sev_es_wr_ghcb_msr(u64 val) +{ + u32 low, high; + + low = (u32)(val); + high = (u32)(val >> 32); + + native_write_msr(MSR_AMD64_SEV_ES_GHCB, low, high); +} + +static int vc_fetch_insn_kernel(struct es_em_ctxt *ctxt, + unsigned char *buffer) +{ + return copy_from_kernel_nofault(buffer, (unsigned char *)ctxt->regs->ip, MAX_INSN_SIZE); +} + +static enum es_result vc_decode_insn(struct es_em_ctxt *ctxt) +{ + char buffer[MAX_INSN_SIZE]; + enum es_result ret; + int res; + + res = vc_fetch_insn_kernel(ctxt, buffer); + if (unlikely(res == -EFAULT)) { + ctxt->fi.vector = X86_TRAP_PF; + ctxt->fi.error_code = 0; + ctxt->fi.cr2 = ctxt->regs->ip; + return ES_EXCEPTION; + } + + insn_init(&ctxt->insn, buffer, MAX_INSN_SIZE - res, 1); + insn_get_length(&ctxt->insn); + + ret = ctxt->insn.immediate.got ? ES_OK : ES_DECODE_FAILED; + + return ret; +} + +static enum es_result vc_write_mem(struct es_em_ctxt *ctxt, + char *dst, char *buf, size_t size) +{ + unsigned long error_code = X86_PF_PROT | X86_PF_WRITE; + char __user *target = (char __user *)dst; + u64 d8; + u32 d4; + u16 d2; + u8 d1; + + switch (size) { + case 1: + memcpy(&d1, buf, 1); + if (put_user(d1, target)) + goto fault; + break; + case 2: + memcpy(&d2, buf, 2); + if (put_user(d2, target)) + goto fault; + break; + case 4: + memcpy(&d4, buf, 4); + if (put_user(d4, target)) + goto fault; + break; + case 8: + memcpy(&d8, buf, 8); + if (put_user(d8, target)) + goto fault; + break; + default: + WARN_ONCE(1, "%s: Invalid size: %zu\n", __func__, size); + return ES_UNSUPPORTED; + } + + return ES_OK; + +fault: + if (user_mode(ctxt->regs)) + error_code |= X86_PF_USER; + + ctxt->fi.vector = X86_TRAP_PF; + ctxt->fi.error_code = error_code; + ctxt->fi.cr2 = (unsigned long)dst; + + return ES_EXCEPTION; +} + +static enum es_result vc_read_mem(struct es_em_ctxt *ctxt, + char *src, char *buf, size_t size) +{ + unsigned long error_code = X86_PF_PROT; + char __user *s = (char __user *)src; + u64 d8; + u32 d4; + u16 d2; + u8 d1; + + switch (size) { + case 1: + if (get_user(d1, s)) + goto fault; + memcpy(buf, &d1, 1); + break; + case 2: + if (get_user(d2, s)) + goto fault; + memcpy(buf, &d2, 2); + break; + case 4: + if (get_user(d4, s)) + goto fault; + memcpy(buf, &d4, 4); + break; + case 8: + if (get_user(d8, s)) + goto fault; + memcpy(buf, &d8, 8); + break; + default: + WARN_ONCE(1, "%s: Invalid size: %zu\n", __func__, size); + return ES_UNSUPPORTED; + } + + return ES_OK; + +fault: + if (user_mode(ctxt->regs)) + error_code |= X86_PF_USER; + + ctxt->fi.vector = X86_TRAP_PF; + ctxt->fi.error_code = error_code; + ctxt->fi.cr2 = (unsigned long)src; + + return ES_EXCEPTION; +} + +/* Include code shared with pre-decompression boot stage */ +#include "sev-es-shared.c" From patchwork Tue Jul 14 12:08:42 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662611 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 090CA13A4 for ; Tue, 14 Jul 2020 12:15:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EDD05222D9 for ; Tue, 14 Jul 2020 12:15:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728494AbgGNMOz (ORCPT ); Tue, 14 Jul 2020 08:14:55 -0400 Received: from 8bytes.org ([81.169.241.247]:52918 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728352AbgGNMK6 (ORCPT ); Tue, 14 Jul 2020 08:10:58 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id B4CF6F89; Tue, 14 Jul 2020 14:10:54 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 40/75] x86/sev-es: Setup early #VC handler Date: Tue, 14 Jul 2020 14:08:42 +0200 Message-Id: <20200714120917.11253-41-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Setup an early handler for #VC exceptions. There is no GHCB mapped yet, so just re-use the vc_no_ghcb_handler. It can only handle CPUID exit-codes, but that should be enough to get the kernel through verify_cpu() and __startup_64() until it runs on virtual addresses. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/processor.h | 1 + arch/x86/include/asm/sev-es.h | 3 +++ arch/x86/kernel/head64.c | 31 +++++++++++++++++++++++++ arch/x86/kernel/head_64.S | 39 ++++++++++++++++++++++++++++++++ 4 files changed, 74 insertions(+) diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 03b7c4ca425a..e6a029b76b3d 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -756,6 +756,7 @@ extern int sysenter_setup(void); /* Defined in head.S */ extern struct desc_ptr early_gdt_descr; +extern struct desc_ptr early_idt_descr; extern void switch_to_new_gdt(int); extern void load_direct_gdt(int); diff --git a/arch/x86/include/asm/sev-es.h b/arch/x86/include/asm/sev-es.h index 7c0807b84546..ec0e112a742b 100644 --- a/arch/x86/include/asm/sev-es.h +++ b/arch/x86/include/asm/sev-es.h @@ -73,4 +73,7 @@ static inline u64 lower_bits(u64 val, unsigned int bits) return (val & mask); } +/* Early IDT entry points for #VC handler */ +extern void vc_no_ghcb(void); + #endif diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index 32080e34ba92..9ea8a0437b66 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -38,6 +38,7 @@ #include #include #include +#include /* * Manage page tables very early on. @@ -537,3 +538,33 @@ void __head early_idt_setup_early_handler(unsigned long descr_addr, unsigned lon native_write_idt_entry(idt, i, &desc); } } + +#ifdef CONFIG_AMD_MEM_ENCRYPT +static void __head set_early_idt_handler(gate_desc *idt, int n, void *handler) +{ + struct idt_data data; + gate_desc desc; + + init_idt_data(&data, n, handler); + idt_init_desc(&desc, &data); + native_write_idt_entry(idt, n, &desc); +} +#endif + +void __head early_idt_setup(struct desc_ptr *descr, unsigned long physbase) +{ + gate_desc *idt = (gate_desc *)descr->address; + void __maybe_unused *handler; + + idt = fixup_pointer(idt, physbase); + +#ifdef CONFIG_AMD_MEM_ENCRYPT + /* VMM Communication Exception */ + handler = fixup_pointer(vc_no_ghcb, physbase); + set_early_idt_handler(idt, X86_TRAP_VC, handler); +#endif + + /* Initialize IDT descriptor and load IDT */ + early_idt_descr.address = (unsigned long)idt; + native_load_idt(&early_idt_descr); +} diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 86473d49619d..3bd4c36d1d36 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -93,6 +93,15 @@ SYM_CODE_START_NOALIGN(startup_64) .Lon_kernel_cs: UNWIND_HINT_EMPTY + /* Setup IDT - Needed for SEV-ES */ + pushq %rsi + /* early_idt_setup - first parameter */ + leaq idt_descr(%rip), %rdi + /* early_idt_setup - second parameter */ + leaq _text(%rip), %rsi + call early_idt_setup + popq %rsi + /* Sanitize CPU configuration */ call verify_cpu @@ -382,6 +391,33 @@ SYM_CODE_START_LOCAL(early_idt_handler_common) jmp restore_regs_and_return_to_kernel SYM_CODE_END(early_idt_handler_common) +#ifdef CONFIG_AMD_MEM_ENCRYPT +/* + * VC Exception handler used during very early boot. The + * early_idt_handler_array can't be used because it returns via the + * paravirtualized INTERRUPT_RETURN and pv-ops don't work that early. + */ +SYM_CODE_START_NOALIGN(vc_no_ghcb) + UNWIND_HINT_IRET_REGS offset=8 + + /* Build pt_regs */ + PUSH_AND_CLEAR_REGS + + /* Call C handler */ + movq %rsp, %rdi + movq ORIG_RAX(%rsp), %rsi + call do_vc_no_ghcb + + /* Unwind pt_regs */ + POP_REGS + + /* Remove Error Code */ + addq $8, %rsp + + /* Pure iret required here - don't use INTERRUPT_RETURN */ + iretq +SYM_CODE_END(vc_no_ghcb) +#endif #define SYM_DATA_START_PAGE_ALIGNED(name) \ SYM_START(name, SYM_L_GLOBAL, .balign PAGE_SIZE) @@ -523,6 +559,9 @@ SYM_DATA_END(level1_fixmap_pgt) SYM_DATA(early_gdt_descr, .word GDT_ENTRIES*8-1) SYM_DATA_LOCAL(early_gdt_descr_base, .quad INIT_PER_CPU_VAR(gdt_page)) +SYM_DATA(early_idt_descr, .word NUM_EXCEPTION_VECTORS * 16) +SYM_DATA_LOCAL(early_idt_descr_base, .quad 0) + .align 16 /* This must match the first entry in level2_kernel_pgt */ SYM_DATA(phys_base, .quad 0x0) From patchwork Tue Jul 14 12:08:43 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662597 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E1C1F618 for ; Tue, 14 Jul 2020 12:14:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CF2B6223C6 for ; Tue, 14 Jul 2020 12:14:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728401AbgGNMLB (ORCPT ); Tue, 14 Jul 2020 08:11:01 -0400 Received: from 8bytes.org ([81.169.241.247]:52886 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728362AbgGNMK7 (ORCPT ); Tue, 14 Jul 2020 08:10:59 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 596E1F79; Tue, 14 Jul 2020 14:10:55 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 41/75] x86/sev-es: Setup GHCB based boot #VC handler Date: Tue, 14 Jul 2020 14:08:43 +0200 Message-Id: <20200714120917.11253-42-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Add the infrastructure to handle #VC exceptions when the kernel runs on virtual addresses and has a GHCB mapped. This handler will be used until the runtime #VC handler takes over. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/segment.h | 2 +- arch/x86/include/asm/sev-es.h | 1 + arch/x86/kernel/head64.c | 6 ++ arch/x86/kernel/sev-es-shared.c | 14 ++-- arch/x86/kernel/sev-es.c | 116 ++++++++++++++++++++++++++++++++ arch/x86/mm/extable.c | 1 + 6 files changed, 132 insertions(+), 8 deletions(-) diff --git a/arch/x86/include/asm/segment.h b/arch/x86/include/asm/segment.h index 6669164abadc..5b648066504c 100644 --- a/arch/x86/include/asm/segment.h +++ b/arch/x86/include/asm/segment.h @@ -230,7 +230,7 @@ #define NUM_EXCEPTION_VECTORS 32 /* Bitmask of exception vectors which push an error code on the stack: */ -#define EXCEPTION_ERRCODE_MASK 0x00027d00 +#define EXCEPTION_ERRCODE_MASK 0x20027d00 #define GDT_SIZE (GDT_ENTRIES*8) #define GDT_ENTRY_TLS_ENTRIES 3 diff --git a/arch/x86/include/asm/sev-es.h b/arch/x86/include/asm/sev-es.h index ec0e112a742b..824e9e6b067c 100644 --- a/arch/x86/include/asm/sev-es.h +++ b/arch/x86/include/asm/sev-es.h @@ -75,5 +75,6 @@ static inline u64 lower_bits(u64 val, unsigned int bits) /* Early IDT entry points for #VC handler */ extern void vc_no_ghcb(void); +extern bool handle_vc_boot_ghcb(struct pt_regs *regs); #endif diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index 9ea8a0437b66..23d492091f3b 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -405,6 +405,12 @@ void __init do_early_exception(struct pt_regs *regs, int trapnr) early_make_pgtable(native_read_cr2())) return; +#ifdef CONFIG_AMD_MEM_ENCRYPT + if (trapnr == X86_TRAP_VC && + handle_vc_boot_ghcb(regs)) + return; +#endif + early_fixup_exception(regs, trapnr); } diff --git a/arch/x86/kernel/sev-es-shared.c b/arch/x86/kernel/sev-es-shared.c index df6750aef3c8..4153b1b1048f 100644 --- a/arch/x86/kernel/sev-es-shared.c +++ b/arch/x86/kernel/sev-es-shared.c @@ -9,7 +9,7 @@ * and is included directly into both code-bases. */ -static void __maybe_unused sev_es_terminate(unsigned int reason) +static void sev_es_terminate(unsigned int reason) { u64 val = GHCB_SEV_TERMINATE; @@ -27,7 +27,7 @@ static void __maybe_unused sev_es_terminate(unsigned int reason) asm volatile("hlt\n" : : : "memory"); } -static bool __maybe_unused sev_es_negotiate_protocol(void) +static bool sev_es_negotiate_protocol(void) { u64 val; @@ -46,7 +46,7 @@ static bool __maybe_unused sev_es_negotiate_protocol(void) return true; } -static void __maybe_unused vc_ghcb_invalidate(struct ghcb *ghcb) +static void vc_ghcb_invalidate(struct ghcb *ghcb) { memset(ghcb->save.valid_bitmap, 0, sizeof(ghcb->save.valid_bitmap)); } @@ -58,9 +58,9 @@ static bool vc_decoding_needed(unsigned long exit_code) exit_code <= SVM_EXIT_LAST_EXCP); } -static enum es_result __maybe_unused vc_init_em_ctxt(struct es_em_ctxt *ctxt, - struct pt_regs *regs, - unsigned long exit_code) +static enum es_result vc_init_em_ctxt(struct es_em_ctxt *ctxt, + struct pt_regs *regs, + unsigned long exit_code) { enum es_result ret = ES_OK; @@ -73,7 +73,7 @@ static enum es_result __maybe_unused vc_init_em_ctxt(struct es_em_ctxt *ctxt, return ret; } -static void __maybe_unused vc_finish_insn(struct es_em_ctxt *ctxt) +static void vc_finish_insn(struct es_em_ctxt *ctxt) { ctxt->regs->ip += ctxt->insn.length; } diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index 0b698b653c0b..bb3e702a71eb 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -7,7 +7,9 @@ * Author: Joerg Roedel */ +#include /* For show_regs() */ #include +#include #include #include @@ -18,6 +20,18 @@ #include #include +/* For early boot hypervisor communication in SEV-ES enabled guests */ +static struct ghcb boot_ghcb_page __bss_decrypted __aligned(PAGE_SIZE); + +/* + * Needs to be in the .data section because we need it NULL before bss is + * cleared + */ +static struct ghcb __initdata *boot_ghcb; + +/* Needed in vc_early_forward_exception */ +void do_early_exception(struct pt_regs *regs, int trapnr); + static inline u64 sev_es_rd_ghcb_msr(void) { return native_read_msr(MSR_AMD64_SEV_ES_GHCB); @@ -161,3 +175,105 @@ static enum es_result vc_read_mem(struct es_em_ctxt *ctxt, /* Include code shared with pre-decompression boot stage */ #include "sev-es-shared.c" + +/* + * This function runs on the first #VC exception after the kernel + * switched to virtual addresses. + */ +static bool __init sev_es_setup_ghcb(void) +{ + /* First make sure the hypervisor talks a supported protocol. */ + if (!sev_es_negotiate_protocol()) + return false; + + /* + * Clear the boot_ghcb. The first exception comes in before the bss + * section is cleared. + */ + memset(&boot_ghcb_page, 0, PAGE_SIZE); + + /* Alright - Make the boot-ghcb public */ + boot_ghcb = &boot_ghcb_page; + + return true; +} + +static void __init vc_early_forward_exception(struct es_em_ctxt *ctxt) +{ + int trapnr = ctxt->fi.vector; + + if (trapnr == X86_TRAP_PF) + native_write_cr2(ctxt->fi.cr2); + + ctxt->regs->orig_ax = ctxt->fi.error_code; + do_early_exception(ctxt->regs, trapnr); +} + +static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt, + struct ghcb *ghcb, + unsigned long exit_code) +{ + enum es_result result; + + switch (exit_code) { + default: + /* + * Unexpected #VC exception + */ + result = ES_UNSUPPORTED; + } + + return result; +} + +bool __init handle_vc_boot_ghcb(struct pt_regs *regs) +{ + unsigned long exit_code = regs->orig_ax; + struct es_em_ctxt ctxt; + enum es_result result; + + /* Do initial setup or terminate the guest */ + if (unlikely(boot_ghcb == NULL && !sev_es_setup_ghcb())) + sev_es_terminate(GHCB_SEV_ES_REASON_GENERAL_REQUEST); + + vc_ghcb_invalidate(boot_ghcb); + + result = vc_init_em_ctxt(&ctxt, regs, exit_code); + if (result == ES_OK) + result = vc_handle_exitcode(&ctxt, boot_ghcb, exit_code); + + /* Done - now check the result */ + switch (result) { + case ES_OK: + vc_finish_insn(&ctxt); + break; + case ES_UNSUPPORTED: + early_printk("PANIC: Unsupported exit-code 0x%02lx in early #VC exception (IP: 0x%lx)\n", + exit_code, regs->ip); + goto fail; + case ES_VMM_ERROR: + early_printk("PANIC: Failure in communication with VMM (exit-code 0x%02lx IP: 0x%lx)\n", + exit_code, regs->ip); + goto fail; + case ES_DECODE_FAILED: + early_printk("PANIC: Failed to decode instruction (exit-code 0x%02lx IP: 0x%lx)\n", + exit_code, regs->ip); + goto fail; + case ES_EXCEPTION: + vc_early_forward_exception(&ctxt); + break; + case ES_RETRY: + /* Nothing to do */ + break; + default: + BUG(); + } + + return true; + +fail: + show_regs(regs); + + while (true) + halt(); +} diff --git a/arch/x86/mm/extable.c b/arch/x86/mm/extable.c index 1d6cb07f4f86..3966749d07ac 100644 --- a/arch/x86/mm/extable.c +++ b/arch/x86/mm/extable.c @@ -5,6 +5,7 @@ #include #include +#include #include #include From patchwork Tue Jul 14 12:08:44 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662605 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 2FCD913B4 for ; Tue, 14 Jul 2020 12:14:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1E5742236F for ; Tue, 14 Jul 2020 12:14:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728392AbgGNMOd (ORCPT ); Tue, 14 Jul 2020 08:14:33 -0400 Received: from 8bytes.org ([81.169.241.247]:53376 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728381AbgGNMK7 (ORCPT ); Tue, 14 Jul 2020 08:10:59 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id D9C9DF8B; Tue, 14 Jul 2020 14:10:55 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , Tom Lendacky , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 42/75] x86/sev-es: Setup per-cpu GHCBs for the runtime handler Date: Tue, 14 Jul 2020 14:08:44 +0200 Message-Id: <20200714120917.11253-43-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Tom Lendacky The runtime handler needs a GHCB per CPU. Set them up and map them unencrypted. Signed-off-by: Tom Lendacky Signed-off-by: Joerg Roedel --- arch/x86/include/asm/mem_encrypt.h | 2 ++ arch/x86/kernel/sev-es.c | 56 +++++++++++++++++++++++++++++- arch/x86/kernel/traps.c | 3 ++ 3 files changed, 60 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/mem_encrypt.h b/arch/x86/include/asm/mem_encrypt.h index 6f61bb93366a..af3e58aa1603 100644 --- a/arch/x86/include/asm/mem_encrypt.h +++ b/arch/x86/include/asm/mem_encrypt.h @@ -48,6 +48,7 @@ int __init early_set_memory_encrypted(unsigned long vaddr, unsigned long size); void __init mem_encrypt_init(void); void __init mem_encrypt_free_decrypted_mem(void); +void __init sev_es_init_vc_handling(void); bool sme_active(void); bool sev_active(void); bool sev_es_active(void); @@ -71,6 +72,7 @@ static inline void __init sme_early_init(void) { } static inline void __init sme_encrypt_kernel(struct boot_params *bp) { } static inline void __init sme_enable(struct boot_params *bp) { } +static inline void sev_es_init_vc_handling(void) { } static inline bool sme_active(void) { return false; } static inline bool sev_active(void) { return false; } static inline bool sev_es_active(void) { return false; } diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index bb3e702a71eb..734afaee378d 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -8,8 +8,13 @@ */ #include /* For show_regs() */ -#include +#include +#include #include +#include +#include +#include +#include #include #include @@ -29,6 +34,13 @@ static struct ghcb boot_ghcb_page __bss_decrypted __aligned(PAGE_SIZE); */ static struct ghcb __initdata *boot_ghcb; +/* #VC handler runtime per-cpu data */ +struct sev_es_runtime_data { + struct ghcb ghcb_page; +}; + +static DEFINE_PER_CPU(struct sev_es_runtime_data*, runtime_data); + /* Needed in vc_early_forward_exception */ void do_early_exception(struct pt_regs *regs, int trapnr); @@ -198,6 +210,48 @@ static bool __init sev_es_setup_ghcb(void) return true; } +static void __init sev_es_alloc_runtime_data(int cpu) +{ + struct sev_es_runtime_data *data; + + data = memblock_alloc(sizeof(*data), PAGE_SIZE); + if (!data) + panic("Can't allocate SEV-ES runtime data"); + + per_cpu(runtime_data, cpu) = data; +} + +static void __init sev_es_init_ghcb(int cpu) +{ + struct sev_es_runtime_data *data; + int err; + + data = per_cpu(runtime_data, cpu); + + err = early_set_memory_decrypted((unsigned long)&data->ghcb_page, + sizeof(data->ghcb_page)); + if (err) + panic("Can not map GHCBs unencrypted"); + + memset(&data->ghcb_page, 0, sizeof(data->ghcb_page)); +} + +void __init sev_es_init_vc_handling(void) +{ + int cpu; + + BUILD_BUG_ON((offsetof(struct sev_es_runtime_data, ghcb_page) % PAGE_SIZE) != 0); + + if (!sev_es_active()) + return; + + /* Initialize per-cpu GHCB pages */ + for_each_possible_cpu(cpu) { + sev_es_alloc_runtime_data(cpu); + sev_es_init_ghcb(cpu); + } +} + static void __init vc_early_forward_exception(struct es_em_ctxt *ctxt) { int trapnr = ctxt->fi.vector; diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index b038695f36c5..907ac2b378a8 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -1081,6 +1081,9 @@ void __init trap_init(void) /* Init cpu_entry_area before IST entries are set up */ setup_cpu_entry_areas(); + /* Init GHCB memory pages when running as an SEV-ES guest */ + sev_es_init_vc_handling(); + idt_setup_traps(); /* From patchwork Tue Jul 14 12:08:45 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662601 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id ABB9913B4 for ; Tue, 14 Jul 2020 12:14:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9BBF62236F for ; Tue, 14 Jul 2020 12:14:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728255AbgGNMOQ (ORCPT ); Tue, 14 Jul 2020 08:14:16 -0400 Received: from 8bytes.org ([81.169.241.247]:53652 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728385AbgGNMLA (ORCPT ); Tue, 14 Jul 2020 08:11:00 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 6604AF8E; Tue, 14 Jul 2020 14:10:56 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 43/75] x86/sev-es: Allocate and Map stacks for #VC handler Date: Tue, 14 Jul 2020 14:08:45 +0200 Message-Id: <20200714120917.11253-44-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Allocate and map an IST stack and a fall-back stack for the #VC handler. The memory for the stacks is allocated only when SEV-ES is active. The #VC handler needs to use an IST stack because it could be raised from kernel space with unsafe stack, e.g. in the SYSCALL entry path. Since the #VC exception can be nested, the #VC handler switches back to the interrupted stack when entered from kernel space. If switching back is not possible the fall-back stack will be used. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/cpu_entry_area.h | 33 +++++++++++++++++---------- arch/x86/kernel/dumpstack_64.c | 8 +++++-- arch/x86/kernel/sev-es.c | 33 +++++++++++++++++++++++++++ 3 files changed, 60 insertions(+), 14 deletions(-) diff --git a/arch/x86/include/asm/cpu_entry_area.h b/arch/x86/include/asm/cpu_entry_area.h index 8902fdb7de13..f87e4c0c16f4 100644 --- a/arch/x86/include/asm/cpu_entry_area.h +++ b/arch/x86/include/asm/cpu_entry_area.h @@ -11,25 +11,29 @@ #ifdef CONFIG_X86_64 /* Macro to enforce the same ordering and stack sizes */ -#define ESTACKS_MEMBERS(guardsize) \ - char DF_stack_guard[guardsize]; \ - char DF_stack[EXCEPTION_STKSZ]; \ - char NMI_stack_guard[guardsize]; \ - char NMI_stack[EXCEPTION_STKSZ]; \ - char DB_stack_guard[guardsize]; \ - char DB_stack[EXCEPTION_STKSZ]; \ - char MCE_stack_guard[guardsize]; \ - char MCE_stack[EXCEPTION_STKSZ]; \ - char IST_top_guard[guardsize]; \ +#define ESTACKS_MEMBERS(guardsize, optional_stack_size) \ + char DF_stack_guard[guardsize]; \ + char DF_stack[EXCEPTION_STKSZ]; \ + char NMI_stack_guard[guardsize]; \ + char NMI_stack[EXCEPTION_STKSZ]; \ + char DB_stack_guard[guardsize]; \ + char DB_stack[EXCEPTION_STKSZ]; \ + char MCE_stack_guard[guardsize]; \ + char MCE_stack[EXCEPTION_STKSZ]; \ + char VC_stack_guard[guardsize]; \ + char VC_stack[optional_stack_size]; \ + char VC2_stack_guard[guardsize]; \ + char VC2_stack[optional_stack_size]; \ + char IST_top_guard[guardsize]; \ /* The exception stacks' physical storage. No guard pages required */ struct exception_stacks { - ESTACKS_MEMBERS(0) + ESTACKS_MEMBERS(0, 0) }; /* The effective cpu entry area mapping with guard pages. */ struct cea_exception_stacks { - ESTACKS_MEMBERS(PAGE_SIZE) + ESTACKS_MEMBERS(PAGE_SIZE, EXCEPTION_STKSZ) }; /* @@ -40,6 +44,8 @@ enum exception_stack_ordering { ESTACK_NMI, ESTACK_DB, ESTACK_MCE, + ESTACK_VC, + ESTACK_VC2, N_EXCEPTION_STACKS }; @@ -139,4 +145,7 @@ static inline struct entry_stack *cpu_entry_stack(int cpu) #define __this_cpu_ist_top_va(name) \ CEA_ESTACK_TOP(__this_cpu_read(cea_exception_stacks), name) +#define __this_cpu_ist_bot_va(name) \ + CEA_ESTACK_BOT(__this_cpu_read(cea_exception_stacks), name) + #endif diff --git a/arch/x86/kernel/dumpstack_64.c b/arch/x86/kernel/dumpstack_64.c index 4a94d38cd141..c49cf594714b 100644 --- a/arch/x86/kernel/dumpstack_64.c +++ b/arch/x86/kernel/dumpstack_64.c @@ -24,11 +24,13 @@ static const char * const exception_stack_names[] = { [ ESTACK_NMI ] = "NMI", [ ESTACK_DB ] = "#DB", [ ESTACK_MCE ] = "#MC", + [ ESTACK_VC ] = "#VC", + [ ESTACK_VC2 ] = "#VC2", }; const char *stack_type_name(enum stack_type type) { - BUILD_BUG_ON(N_EXCEPTION_STACKS != 4); + BUILD_BUG_ON(N_EXCEPTION_STACKS != 6); if (type == STACK_TYPE_IRQ) return "IRQ"; @@ -79,6 +81,8 @@ struct estack_pages estack_pages[CEA_ESTACK_PAGES] ____cacheline_aligned = { EPAGERANGE(NMI), EPAGERANGE(DB), EPAGERANGE(MCE), + EPAGERANGE(VC), + EPAGERANGE(VC2), }; static bool in_exception_stack(unsigned long *stack, struct stack_info *info) @@ -88,7 +92,7 @@ static bool in_exception_stack(unsigned long *stack, struct stack_info *info) struct pt_regs *regs; unsigned int k; - BUILD_BUG_ON(N_EXCEPTION_STACKS != 4); + BUILD_BUG_ON(N_EXCEPTION_STACKS != 6); begin = (unsigned long)__this_cpu_read(cea_exception_stacks); /* diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index 734afaee378d..64002d86a237 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -17,6 +17,7 @@ #include #include +#include #include #include #include @@ -37,10 +38,41 @@ static struct ghcb __initdata *boot_ghcb; /* #VC handler runtime per-cpu data */ struct sev_es_runtime_data { struct ghcb ghcb_page; + + /* Physical storage for the per-cpu IST stack of the #VC handler */ + char ist_stack[EXCEPTION_STKSZ] __aligned(PAGE_SIZE); + + /* + * Physical storage for the per-cpu fall-back stack of the #VC handler. + * The fall-back stack is used when it is not safe to switch back to the + * interrupted stack in the #VC entry code. + */ + char fallback_stack[EXCEPTION_STKSZ] __aligned(PAGE_SIZE); }; static DEFINE_PER_CPU(struct sev_es_runtime_data*, runtime_data); +static void __init sev_es_setup_vc_stacks(int cpu) +{ + struct sev_es_runtime_data *data; + struct cpu_entry_area *cea; + unsigned long vaddr; + phys_addr_t pa; + + data = per_cpu(runtime_data, cpu); + cea = get_cpu_entry_area(cpu); + + /* Map #VC IST stack */ + vaddr = CEA_ESTACK_BOT(&cea->estacks, VC); + pa = __pa(data->ist_stack); + cea_set_pte((void *)vaddr, pa, PAGE_KERNEL); + + /* Map VC fall-back stack */ + vaddr = CEA_ESTACK_BOT(&cea->estacks, VC2); + pa = __pa(data->fallback_stack); + cea_set_pte((void *)vaddr, pa, PAGE_KERNEL); +} + /* Needed in vc_early_forward_exception */ void do_early_exception(struct pt_regs *regs, int trapnr); @@ -249,6 +281,7 @@ void __init sev_es_init_vc_handling(void) for_each_possible_cpu(cpu) { sev_es_alloc_runtime_data(cpu); sev_es_init_ghcb(cpu); + sev_es_setup_vc_stacks(cpu); } } From patchwork Tue Jul 14 12:08:46 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662599 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 36FFA618 for ; Tue, 14 Jul 2020 12:14:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 27EF1223C6 for ; Tue, 14 Jul 2020 12:14:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728548AbgGNMOR (ORCPT ); Tue, 14 Jul 2020 08:14:17 -0400 Received: from 8bytes.org ([81.169.241.247]:52918 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728376AbgGNMLA (ORCPT ); Tue, 14 Jul 2020 08:11:00 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id E55FFF8C; Tue, 14 Jul 2020 14:10:56 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 44/75] x86/sev-es: Allocate and setup IST entry for #VC Date: Tue, 14 Jul 2020 14:08:46 +0200 Message-Id: <20200714120917.11253-45-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Allocate IST entry number 4 for the #VC handler and setup it up in the per-cpu TSS. This will setup the TSS for all CPUs before they even start, so that the boot-code for secondary CPUs can handle #VC exceptions. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/page_64_types.h | 1 + arch/x86/kernel/sev-es.c | 5 +++++ 2 files changed, 6 insertions(+) diff --git a/arch/x86/include/asm/page_64_types.h b/arch/x86/include/asm/page_64_types.h index 288b065955b7..d0c6c10c18a0 100644 --- a/arch/x86/include/asm/page_64_types.h +++ b/arch/x86/include/asm/page_64_types.h @@ -28,6 +28,7 @@ #define IST_INDEX_NMI 1 #define IST_INDEX_DB 2 #define IST_INDEX_MCE 3 +#define IST_INDEX_VC 4 /* * Set __PAGE_OFFSET to the most negative possible address + diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index 64002d86a237..d415368f16ec 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -56,11 +56,13 @@ static void __init sev_es_setup_vc_stacks(int cpu) { struct sev_es_runtime_data *data; struct cpu_entry_area *cea; + struct tss_struct *tss; unsigned long vaddr; phys_addr_t pa; data = per_cpu(runtime_data, cpu); cea = get_cpu_entry_area(cpu); + tss = per_cpu_ptr(&cpu_tss_rw, cpu); /* Map #VC IST stack */ vaddr = CEA_ESTACK_BOT(&cea->estacks, VC); @@ -71,6 +73,9 @@ static void __init sev_es_setup_vc_stacks(int cpu) vaddr = CEA_ESTACK_BOT(&cea->estacks, VC2); pa = __pa(data->fallback_stack); cea_set_pte((void *)vaddr, pa, PAGE_KERNEL); + + /* Set IST entry in TSS */ + tss->x86_tss.ist[IST_INDEX_VC] = CEA_ESTACK_TOP(&cea->estacks, VC); } /* Needed in vc_early_forward_exception */ From patchwork Tue Jul 14 12:08:47 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662595 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 2CA74618 for ; Tue, 14 Jul 2020 12:14:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1DD372236F for ; Tue, 14 Jul 2020 12:14:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728263AbgGNMOJ (ORCPT ); Tue, 14 Jul 2020 08:14:09 -0400 Received: from 8bytes.org ([81.169.241.247]:53718 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728399AbgGNMLB (ORCPT ); Tue, 14 Jul 2020 08:11:01 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 728A9F91; Tue, 14 Jul 2020 14:10:57 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 45/75] x86/sev-es: Adjust #VC IST Stack on entering NMI handler Date: Tue, 14 Jul 2020 14:08:47 +0200 Message-Id: <20200714120917.11253-46-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel When an NMI hits in the #VC handler entry code before it switched to another stack, any subsequent #VC exception in the NMI code-path will overwrite the interrupted #VC handlers stack. Make sure this doesn't happen by explicitly adjusting the #VC IST entry in the NMI handler for the time in can cause #VC exceptions. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/sev-es.h | 8 +++++ arch/x86/kernel/nmi.c | 6 ++++ arch/x86/kernel/sev-es.c | 61 +++++++++++++++++++++++++++++++++++ arch/x86/kernel/traps.c | 2 ++ 4 files changed, 77 insertions(+) diff --git a/arch/x86/include/asm/sev-es.h b/arch/x86/include/asm/sev-es.h index 824e9e6b067c..330140a189be 100644 --- a/arch/x86/include/asm/sev-es.h +++ b/arch/x86/include/asm/sev-es.h @@ -77,4 +77,12 @@ static inline u64 lower_bits(u64 val, unsigned int bits) extern void vc_no_ghcb(void); extern bool handle_vc_boot_ghcb(struct pt_regs *regs); +#ifdef CONFIG_AMD_MEM_ENCRYPT +extern void sev_es_ist_enter(struct pt_regs *regs); +extern void sev_es_ist_exit(void); +#else +static inline void sev_es_ist_enter(struct pt_regs *regs) { } +static inline void sev_es_ist_exit(void) { } +#endif + #endif diff --git a/arch/x86/kernel/nmi.c b/arch/x86/kernel/nmi.c index d7c5e44b26f7..d94a5bb0bebc 100644 --- a/arch/x86/kernel/nmi.c +++ b/arch/x86/kernel/nmi.c @@ -33,6 +33,7 @@ #include #include #include +#include #define CREATE_TRACE_POINTS #include @@ -489,6 +490,9 @@ DEFINE_IDTENTRY_RAW(exc_nmi) this_cpu_write(nmi_cr2, read_cr2()); nmi_restart: + /* Needs to happen before DR7 is accessed */ + sev_es_ist_enter(regs); + this_cpu_write(nmi_dr7, local_db_save()); nmi_enter(); @@ -502,6 +506,8 @@ DEFINE_IDTENTRY_RAW(exc_nmi) local_db_restore(this_cpu_read(nmi_dr7)); + sev_es_ist_exit(); + if (unlikely(this_cpu_read(nmi_cr2) != read_cr2())) write_cr2(this_cpu_read(nmi_cr2)); if (this_cpu_dec_return(nmi_state)) diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index d415368f16ec..2a7cc72db1d5 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -78,6 +78,67 @@ static void __init sev_es_setup_vc_stacks(int cpu) tss->x86_tss.ist[IST_INDEX_VC] = CEA_ESTACK_TOP(&cea->estacks, VC); } +static bool on_vc_stack(unsigned long sp) +{ + return ((sp >= __this_cpu_ist_bot_va(VC)) && (sp < __this_cpu_ist_top_va(VC))); +} + +/* + * This function handles the case when an NMI or an NMI-like exception + * like #DB is raised in the #VC exception handler entry code. In this + * case the IST entry for VC must be adjusted, so that any subsequent VC + * exception will not overwrite the stack contents of the interrupted VC + * handler. + * + * The IST entry is adjusted unconditionally so that it can be also be + * unconditionally back-adjusted in sev_es_nmi_exit(). Otherwise a + * nested nmi_exit() call (#VC->NMI->#DB) may back-adjust the IST entry + * too early. + */ +void noinstr sev_es_ist_enter(struct pt_regs *regs) +{ + unsigned long old_ist, new_ist; + unsigned long *p; + + if (!sev_es_active()) + return; + + /* Read old IST entry */ + old_ist = __this_cpu_read(cpu_tss_rw.x86_tss.ist[IST_INDEX_VC]); + + /* Make room on the IST stack */ + if (on_vc_stack(regs->sp)) + new_ist = ALIGN_DOWN(regs->sp, 8) - sizeof(old_ist); + else + new_ist = old_ist - sizeof(old_ist); + + /* Store old IST entry */ + p = (unsigned long *)new_ist; + *p = old_ist; + + /* Set new IST entry */ + this_cpu_write(cpu_tss_rw.x86_tss.ist[IST_INDEX_VC], new_ist); +} + +void noinstr sev_es_ist_exit(void) +{ + unsigned long ist; + unsigned long *p; + + if (!sev_es_active()) + return; + + /* Read IST entry */ + ist = __this_cpu_read(cpu_tss_rw.x86_tss.ist[IST_INDEX_VC]); + + if (WARN_ON(ist == __this_cpu_ist_top_va(VC))) + return; + + /* Read back old IST entry and write it to the TSS */ + p = (unsigned long *)ist; + this_cpu_write(cpu_tss_rw.x86_tss.ist[IST_INDEX_VC], *p); +} + /* Needed in vc_early_forward_exception */ void do_early_exception(struct pt_regs *regs, int trapnr); diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index 907ac2b378a8..59d17e541df9 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -59,6 +59,7 @@ #include #include #include +#include #ifdef CONFIG_X86_64 #include @@ -733,6 +734,7 @@ static bool is_sysenter_singlestep(struct pt_regs *regs) static __always_inline void debug_enter(unsigned long *dr6, unsigned long *dr7) { + /* * Disable breakpoints during exception handling; recursive exceptions * are exceedingly 'fun'. From patchwork Tue Jul 14 12:08:48 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662591 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 15D52618 for ; Tue, 14 Jul 2020 12:13:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 06D3F2236F for ; Tue, 14 Jul 2020 12:13:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728492AbgGNMN4 (ORCPT ); Tue, 14 Jul 2020 08:13:56 -0400 Received: from 8bytes.org ([81.169.241.247]:52886 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728406AbgGNMLC (ORCPT ); Tue, 14 Jul 2020 08:11:02 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 716D8FB4; Tue, 14 Jul 2020 14:10:58 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 46/75] x86/dumpstack/64: Add noinstr version of get_stack_info() Date: Tue, 14 Jul 2020 14:08:48 +0200 Message-Id: <20200714120917.11253-47-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel The get_stack_info functionality is needed in the entry code for the #VC exception handler. Provide a version of it in the .text.noinstr section which can be called safely from there. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/stacktrace.h | 2 ++ arch/x86/kernel/dumpstack.c | 7 +++--- arch/x86/kernel/dumpstack_64.c | 39 ++++++++++++++++++------------- arch/x86/mm/cpu_entry_area.c | 3 ++- 4 files changed, 31 insertions(+), 20 deletions(-) diff --git a/arch/x86/include/asm/stacktrace.h b/arch/x86/include/asm/stacktrace.h index 5ae5a68e469d..49600643faba 100644 --- a/arch/x86/include/asm/stacktrace.h +++ b/arch/x86/include/asm/stacktrace.h @@ -35,6 +35,8 @@ bool in_entry_stack(unsigned long *stack, struct stack_info *info); int get_stack_info(unsigned long *stack, struct task_struct *task, struct stack_info *info, unsigned long *visit_mask); +bool get_stack_info_noinstr(unsigned long *stack, struct task_struct *task, + struct stack_info *info); const char *stack_type_name(enum stack_type type); diff --git a/arch/x86/kernel/dumpstack.c b/arch/x86/kernel/dumpstack.c index b037cfa7c0c5..df9757699485 100644 --- a/arch/x86/kernel/dumpstack.c +++ b/arch/x86/kernel/dumpstack.c @@ -29,8 +29,8 @@ static int die_counter; static struct pt_regs exec_summary_regs; -bool in_task_stack(unsigned long *stack, struct task_struct *task, - struct stack_info *info) +bool noinstr in_task_stack(unsigned long *stack, struct task_struct *task, + struct stack_info *info) { unsigned long *begin = task_stack_page(task); unsigned long *end = task_stack_page(task) + THREAD_SIZE; @@ -46,7 +46,8 @@ bool in_task_stack(unsigned long *stack, struct task_struct *task, return true; } -bool in_entry_stack(unsigned long *stack, struct stack_info *info) +/* Called from get_stack_info_noinstr - so must be noinstr too */ +bool noinstr in_entry_stack(unsigned long *stack, struct stack_info *info) { struct entry_stack *ss = cpu_entry_stack(smp_processor_id()); diff --git a/arch/x86/kernel/dumpstack_64.c b/arch/x86/kernel/dumpstack_64.c index c49cf594714b..5a85730eb0ca 100644 --- a/arch/x86/kernel/dumpstack_64.c +++ b/arch/x86/kernel/dumpstack_64.c @@ -85,7 +85,7 @@ struct estack_pages estack_pages[CEA_ESTACK_PAGES] ____cacheline_aligned = { EPAGERANGE(VC2), }; -static bool in_exception_stack(unsigned long *stack, struct stack_info *info) +static bool __always_inline in_exception_stack(unsigned long *stack, struct stack_info *info) { unsigned long begin, end, stk = (unsigned long)stack; const struct estack_pages *ep; @@ -126,7 +126,7 @@ static bool in_exception_stack(unsigned long *stack, struct stack_info *info) return true; } -static bool in_irq_stack(unsigned long *stack, struct stack_info *info) +static bool __always_inline in_irq_stack(unsigned long *stack, struct stack_info *info) { unsigned long *end = (unsigned long *)this_cpu_read(hardirq_stack_ptr); unsigned long *begin = end - (IRQ_STACK_SIZE / sizeof(long)); @@ -151,32 +151,38 @@ static bool in_irq_stack(unsigned long *stack, struct stack_info *info) return true; } -int get_stack_info(unsigned long *stack, struct task_struct *task, - struct stack_info *info, unsigned long *visit_mask) +bool noinstr get_stack_info_noinstr(unsigned long *stack, struct task_struct *task, + struct stack_info *info) { - if (!stack) - goto unknown; - - task = task ? : current; - if (in_task_stack(stack, task, info)) - goto recursion_check; + return true; if (task != current) - goto unknown; + return false; if (in_exception_stack(stack, info)) - goto recursion_check; + return true; if (in_irq_stack(stack, info)) - goto recursion_check; + return true; if (in_entry_stack(stack, info)) - goto recursion_check; + return true; - goto unknown; + return false; +} + +int get_stack_info(unsigned long *stack, struct task_struct *task, + struct stack_info *info, unsigned long *visit_mask) +{ + task = task ? : current; + + if (!stack) + goto unknown; + + if (!get_stack_info_noinstr(stack, task, info)) + goto unknown; -recursion_check: /* * Make sure we don't iterate through any given stack more than once. * If it comes up a second time then there's something wrong going on: @@ -196,4 +202,5 @@ int get_stack_info(unsigned long *stack, struct task_struct *task, unknown: info->type = STACK_TYPE_UNKNOWN; return -EINVAL; + } diff --git a/arch/x86/mm/cpu_entry_area.c b/arch/x86/mm/cpu_entry_area.c index 770b613790b3..f5e1e60c9095 100644 --- a/arch/x86/mm/cpu_entry_area.c +++ b/arch/x86/mm/cpu_entry_area.c @@ -21,7 +21,8 @@ DEFINE_PER_CPU(struct cea_exception_stacks*, cea_exception_stacks); DECLARE_PER_CPU_PAGE_ALIGNED(struct doublefault_stack, doublefault_stack); #endif -struct cpu_entry_area *get_cpu_entry_area(int cpu) +/* Is called from entry code, so must be noinstr */ +noinstr struct cpu_entry_area *get_cpu_entry_area(int cpu) { unsigned long va = CPU_ENTRY_AREA_PER_CPU + cpu * CPU_ENTRY_AREA_SIZE; BUILD_BUG_ON(sizeof(struct cpu_entry_area) % PAGE_SIZE != 0); From patchwork Tue Jul 14 12:08:49 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662593 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 5B29913B4 for ; Tue, 14 Jul 2020 12:14:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 43D112236F for ; Tue, 14 Jul 2020 12:14:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728895AbgGNMN5 (ORCPT ); Tue, 14 Jul 2020 08:13:57 -0400 Received: from 8bytes.org ([81.169.241.247]:53376 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728413AbgGNMLC (ORCPT ); Tue, 14 Jul 2020 08:11:02 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id EFDB4F95; Tue, 14 Jul 2020 14:10:58 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 47/75] x86/entry/64: Add entry code for #VC handler Date: Tue, 14 Jul 2020 14:08:49 +0200 Message-Id: <20200714120917.11253-48-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel The #VC handler needs special entry code because: 1. It runs on an IST stack 2. It needs to be able to handle nested #VC exceptions To make this work the entry code is implemented to pretend it doesn't use an IST stack. When entered from user-mode or early SYSCALL entry path it switches to the task stack, if entered from kernel-mode it tries to switch back to the previous stack in the IRET frame. The stack found in the IRET frame is validated first, and if it is not safe to use it for the #VC handler, the code will switch to a fall-back stack (the #VC2 IST stack). From there it can cause nested exceptions again. Signed-off-by: Joerg Roedel --- arch/x86/entry/entry_64.S | 78 +++++++++++++++++++++++++++++++++ arch/x86/include/asm/idtentry.h | 44 +++++++++++++++++++ arch/x86/include/asm/proto.h | 1 + arch/x86/include/asm/traps.h | 1 + arch/x86/kernel/traps.c | 51 +++++++++++++++++++++ 5 files changed, 175 insertions(+) diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index d2a00c97e53f..4168d9cd95c0 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -100,6 +100,8 @@ SYM_CODE_START(entry_SYSCALL_64) SWITCH_TO_KERNEL_CR3 scratch_reg=%rsp movq PER_CPU_VAR(cpu_current_top_of_stack), %rsp +SYM_INNER_LABEL(entry_SYSCALL_64_safe_stack, SYM_L_GLOBAL) + /* Construct struct pt_regs on stack */ pushq $__USER_DS /* pt_regs->ss */ pushq PER_CPU_VAR(cpu_tss_rw + TSS_sp2) /* pt_regs->sp */ @@ -448,6 +450,82 @@ _ASM_NOKPROBE(\asmsym) SYM_CODE_END(\asmsym) .endm +/** + * idtentry_vc - Macro to generate entry stub for #VC + * @vector: Vector number + * @asmsym: ASM symbol for the entry point + * @cfunc: C function to be called + * + * The macro emits code to set up the kernel context for #VC. The #VC handler + * runs on an IST stack and needs to be able to cause nested #VC exceptions. + * + * To make this work the #VC entry code tries its best to pretend it doesn't use + * an IST stack by switching to the task stack if coming from user-space (which + * includes early SYSCALL entry path) or back to the stack in the IRET frame if + * entered from kernel-mode. + * + * If entered from kernel-mode the return stack is validated first, and if it is + * not safe to use (e.g. because it points to the entry stack) the #VC handler + * will switch to a fall-back stack (VC2) and call a special handler function. + * + * The macro is only used for one vector, but it is planned to extend it in the + * future for the #HV exception. + */ +.macro idtentry_vc vector asmsym cfunc +SYM_CODE_START(\asmsym) + UNWIND_HINT_IRET_REGS + ASM_CLAC + + /* + * If the entry is from userspace, switch stacks and treat it as + * a normal entry. + */ + testb $3, CS-ORIG_RAX(%rsp) + jnz .Lfrom_usermode_switch_stack_\@ + + /* + * paranoid_entry returns SWAPGS flag for paranoid_exit in EBX. + * EBX == 0 -> SWAPGS, EBX == 1 -> no SWAPGS + */ + call paranoid_entry + + UNWIND_HINT_REGS + + /* + * Switch off the IST stack to make it free for nested exceptions. The + * vc_switch_off_ist() function will switch back to the interrupted + * stack if it is safe to do so. If not it switches to the VC fall-back + * stack. + */ + movq %rsp, %rdi /* pt_regs pointer */ + call vc_switch_off_ist + movq %rax, %rsp /* Switch to new stack */ + + UNWIND_HINT_REGS + + /* Update pt_regs */ + movq ORIG_RAX(%rsp), %rsi /* get error code into 2nd argument*/ + movq $-1, ORIG_RAX(%rsp) /* no syscall to restart */ + + movq %rsp, %rdi /* pt_regs pointer */ + + call \cfunc + + /* + * No need to switch back to the IST stack. The current stack is either + * identical to the stack in the IRET frame or the VC fall-back stack, + * so it is definitly mapped even with PTI enabled. + */ + jmp paranoid_exit + + /* Switch to the regular task stack */ +.Lfrom_usermode_switch_stack_\@: + idtentry_body safe_stack_\cfunc, has_error_code=1 + +_ASM_NOKPROBE(\asmsym) +SYM_CODE_END(\asmsym) +.endm + /* * Double fault entry. Straight paranoid. No checks from which context * this comes because for the espfix induced #DF this would do the wrong diff --git a/arch/x86/include/asm/idtentry.h b/arch/x86/include/asm/idtentry.h index eeac6dc2adaa..c38494b2bb54 100644 --- a/arch/x86/include/asm/idtentry.h +++ b/arch/x86/include/asm/idtentry.h @@ -312,6 +312,18 @@ static __always_inline void __##func(struct pt_regs *regs) DECLARE_IDTENTRY_RAW(vector, func); \ __visible void noist_##func(struct pt_regs *regs) +/** + * DECLARE_IDTENTRY_VC - Declare functions for the VC entry point + * @vector: Vector number (ignored for C) + * @func: Function name of the entry point + * + * Maps to DECLARE_IDTENTRY_RAW_ERRORCODE, but declares also the + * safe_stack C handler. + */ +#define DECLARE_IDTENTRY_VC(vector, func) \ + DECLARE_IDTENTRY_RAW_ERRORCODE(vector, func); \ + __visible noinstr void safe_stack_##func(struct pt_regs *regs, unsigned long error_code) + /** * DEFINE_IDTENTRY_IST - Emit code for IST entry points * @func: Function name of the entry point @@ -351,6 +363,35 @@ static __always_inline void __##func(struct pt_regs *regs) #define DEFINE_IDTENTRY_DF(func) \ DEFINE_IDTENTRY_RAW_ERRORCODE(func) +/** + * DEFINE_IDTENTRY_VC_SAFE_STACK - Emit code for VMM communication handler + which runs on a safe stack. + * @func: Function name of the entry point + * + * Maps to DEFINE_IDTENTRY_RAW_ERRORCODE + */ +#define DEFINE_IDTENTRY_VC_SAFE_STACK(func) \ + DEFINE_IDTENTRY_RAW_ERRORCODE(safe_stack_##func) + +/** + * DEFINE_IDTENTRY_VC_IST - Emit code for VMM communication handler + which runs on the VC fall-back stack + * @func: Function name of the entry point + * + * Maps to DEFINE_IDTENTRY_RAW_ERRORCODE + */ +#define DEFINE_IDTENTRY_VC_IST(func) \ + DEFINE_IDTENTRY_RAW_ERRORCODE(ist_##func) + +/** + * DEFINE_IDTENTRY_VC - Emit code for VMM communication handler + * @func: Function name of the entry point + * + * Maps to DEFINE_IDTENTRY_RAW_ERRORCODE + */ +#define DEFINE_IDTENTRY_VC(func) \ + DEFINE_IDTENTRY_RAW_ERRORCODE(func) + #else /* CONFIG_X86_64 */ /** @@ -437,6 +478,9 @@ __visible noinstr void func(struct pt_regs *regs, \ # define DECLARE_IDTENTRY_XENCB(vector, func) \ DECLARE_IDTENTRY(vector, func) +# define DECLARE_IDTENTRY_VC(vector, func) \ + idtentry_vc vector asm_##func func + #else # define DECLARE_IDTENTRY_MCE(vector, func) \ DECLARE_IDTENTRY(vector, func) diff --git a/arch/x86/include/asm/proto.h b/arch/x86/include/asm/proto.h index 6e81788a30c1..40f1f0cb73d7 100644 --- a/arch/x86/include/asm/proto.h +++ b/arch/x86/include/asm/proto.h @@ -10,6 +10,7 @@ void syscall_init(void); #ifdef CONFIG_X86_64 void entry_SYSCALL_64(void); +void entry_SYSCALL_64_safe_stack(void); long do_arch_prctl_64(struct task_struct *task, int option, unsigned long arg2); #endif diff --git a/arch/x86/include/asm/traps.h b/arch/x86/include/asm/traps.h index 6a308355ea29..1b86bb3abc56 100644 --- a/arch/x86/include/asm/traps.h +++ b/arch/x86/include/asm/traps.h @@ -15,6 +15,7 @@ asmlinkage __visible notrace struct pt_regs *sync_regs(struct pt_regs *eregs); asmlinkage __visible notrace struct bad_iret_stack *fixup_bad_iret(struct bad_iret_stack *s); void __init trap_init(void); +asmlinkage __visible noinstr struct pt_regs *vc_switch_off_ist(struct pt_regs *eregs); #endif #ifdef CONFIG_X86_F00F_BUG diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index 59d17e541df9..c43b12f3f339 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -43,6 +43,7 @@ #include #include #include +#include #include #include #include @@ -676,6 +677,56 @@ asmlinkage __visible noinstr struct pt_regs *sync_regs(struct pt_regs *eregs) return regs; } +#ifdef CONFIG_AMD_MEM_ENCRYPT +asmlinkage __visible noinstr struct pt_regs *vc_switch_off_ist(struct pt_regs *eregs) +{ + unsigned long sp, *stack; + struct stack_info info; + struct pt_regs *regs; + + /* + * In the SYSCALL entry path the RSP value comes from user-space - don't + * trust it and switch to the current kernel stack + */ + if (eregs->ip >= (unsigned long)entry_SYSCALL_64 && + eregs->ip < (unsigned long)entry_SYSCALL_64_safe_stack) { + sp = this_cpu_read(cpu_current_top_of_stack); + goto sync; + } + + /* + * From here on the the RSP value is trusted - more RSP sanity checks + * need to happen above. + * + * Check whether entry happened from a safe stack. + */ + sp = eregs->sp; + stack = (unsigned long *)sp; + get_stack_info_noinstr(stack, current, &info); + + /* + * Don't sync to entry stack or other unknown stacks - use the fall-back + * stack instead. + */ + if (info.type == STACK_TYPE_UNKNOWN || info.type == STACK_TYPE_ENTRY || + info.type >= STACK_TYPE_EXCEPTION_LAST) + sp = __this_cpu_ist_top_va(VC2); + +sync: + /* + * Found a safe stack - switch to it as if the entry didn't happen via + * IST stack. The code below only copies pt_regs, the real switch happens + * in assembly code. + */ + sp = ALIGN_DOWN(sp, 8) - sizeof(*regs); + + regs = (struct pt_regs *)sp; + *regs = *eregs; + + return regs; +} +#endif + struct bad_iret_stack { void *error_entry_ret; struct pt_regs regs; From patchwork Tue Jul 14 12:08:50 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662589 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4F0AE618 for ; Tue, 14 Jul 2020 12:13:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3ADD922370 for ; Tue, 14 Jul 2020 12:13:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728444AbgGNMNt (ORCPT ); Tue, 14 Jul 2020 08:13:49 -0400 Received: from 8bytes.org ([81.169.241.247]:53652 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728421AbgGNMLD (ORCPT ); Tue, 14 Jul 2020 08:11:03 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 78A37FB9; Tue, 14 Jul 2020 14:10:59 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , Tom Lendacky , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 48/75] x86/sev-es: Add Runtime #VC Exception Handler Date: Tue, 14 Jul 2020 14:08:50 +0200 Message-Id: <20200714120917.11253-49-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Tom Lendacky Add the handlers for #VC exceptions invoked at runtime. Signed-off-by: Tom Lendacky Signed-off-by: Joerg Roedel --- arch/x86/include/asm/idtentry.h | 5 + arch/x86/kernel/idt.c | 11 +- arch/x86/kernel/sev-es.c | 231 +++++++++++++++++++++++++++++++- 3 files changed, 239 insertions(+), 8 deletions(-) diff --git a/arch/x86/include/asm/idtentry.h b/arch/x86/include/asm/idtentry.h index c38494b2bb54..1e25c7b5d5e2 100644 --- a/arch/x86/include/asm/idtentry.h +++ b/arch/x86/include/asm/idtentry.h @@ -614,6 +614,11 @@ DECLARE_IDTENTRY_RAW(X86_TRAP_DB, xenpv_exc_debug); /* #DF */ DECLARE_IDTENTRY_DF(X86_TRAP_DF, exc_double_fault); +/* #VC */ +#ifdef CONFIG_AMD_MEM_ENCRYPT +DECLARE_IDTENTRY_VC(X86_TRAP_VC, exc_vmm_communication); +#endif + #ifdef CONFIG_XEN_PV DECLARE_IDTENTRY_XENCB(X86_TRAP_OTHER, exc_xen_hypervisor_callback); #endif diff --git a/arch/x86/kernel/idt.c b/arch/x86/kernel/idt.c index d3f0c8133300..f5242c6b5a43 100644 --- a/arch/x86/kernel/idt.c +++ b/arch/x86/kernel/idt.c @@ -229,11 +229,14 @@ static const __initconst struct idt_data early_pf_idts[] = { * cpu_init() when the TSS has been initialized. */ static const __initconst struct idt_data ist_idts[] = { - ISTG(X86_TRAP_DB, asm_exc_debug, IST_INDEX_DB), - ISTG(X86_TRAP_NMI, asm_exc_nmi, IST_INDEX_NMI), - ISTG(X86_TRAP_DF, asm_exc_double_fault, IST_INDEX_DF), + ISTG(X86_TRAP_DB, asm_exc_debug, IST_INDEX_DB), + ISTG(X86_TRAP_NMI, asm_exc_nmi, IST_INDEX_NMI), + ISTG(X86_TRAP_DF, asm_exc_double_fault, IST_INDEX_DF), #ifdef CONFIG_X86_MCE - ISTG(X86_TRAP_MC, asm_exc_machine_check, IST_INDEX_MCE), + ISTG(X86_TRAP_MC, asm_exc_machine_check, IST_INDEX_MCE), +#endif +#ifdef CONFIG_AMD_MEM_ENCRYPT + ISTG(X86_TRAP_VC, asm_exc_vmm_communication, IST_INDEX_VC), #endif }; diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index 2a7cc72db1d5..156914d8e103 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -7,9 +7,12 @@ * Author: Joerg Roedel */ +#define pr_fmt(fmt) "SEV-ES: " fmt + #include /* For show_regs() */ #include #include +#include #include #include #include @@ -22,8 +25,7 @@ #include #include #include -#include -#include +#include #include /* For early boot hypervisor communication in SEV-ES enabled guests */ @@ -48,10 +50,42 @@ struct sev_es_runtime_data { * interrupted stack in the #VC entry code. */ char fallback_stack[EXCEPTION_STKSZ] __aligned(PAGE_SIZE); + + /* + * Reserve one page per CPU as backup storage for the unencrypted GHCB. + * It is needed when an NMI happens while the #VC handler uses the real + * GHCB, and the NMI handler itself is causing another #VC exception. In + * that case the GHCB content of the first handler needs to be backed up + * and restored. + */ + struct ghcb backup_ghcb; + + /* + * Mark the per-cpu GHCBs as in-use to detect nested #VC exceptions. + * There is no need for it to be atomic, because nothing is written to + * the GHCB between the read and the write of ghcb_active. So it is safe + * to use it when a nested #VC exception happens before the write. + * + * This is necessary for example in the #VC->NMI->#VC case when the NMI + * happens while the first #VC handler uses the GHCB. When the NMI code + * raises a second #VC handler it might overwrite the contents of the + * GHCB written by the first handler. To avoid this the content of the + * GHCB is saved and restored when the GHCB is detected to be in use + * already. + */ + bool ghcb_active; + bool backup_ghcb_active; +}; + +struct ghcb_state { + struct ghcb *ghcb; }; static DEFINE_PER_CPU(struct sev_es_runtime_data*, runtime_data); +/* Needed in vc_early_forward_exception */ +void do_early_exception(struct pt_regs *regs, int trapnr); + static void __init sev_es_setup_vc_stacks(int cpu) { struct sev_es_runtime_data *data; @@ -139,8 +173,52 @@ void noinstr sev_es_ist_exit(void) this_cpu_write(cpu_tss_rw.x86_tss.ist[IST_INDEX_VC], *p); } -/* Needed in vc_early_forward_exception */ -void do_early_exception(struct pt_regs *regs, int trapnr); +static __always_inline struct ghcb *sev_es_get_ghcb(struct ghcb_state *state) +{ + struct sev_es_runtime_data *data; + struct ghcb *ghcb; + + data = this_cpu_read(runtime_data); + ghcb = &data->ghcb_page; + + if (unlikely(data->ghcb_active)) { + /* GHCB is already in use - save its contents */ + + if (unlikely(data->backup_ghcb_active)) + return NULL; + + /* Mark backup_ghcb active before writing to it */ + data->backup_ghcb_active = true; + + state->ghcb = &data->backup_ghcb; + + /* Backup GHCB content */ + *state->ghcb = *ghcb; + } else { + state->ghcb = NULL; + data->ghcb_active = true; + } + + return ghcb; +} + +static __always_inline void sev_es_put_ghcb(struct ghcb_state *state) +{ + struct sev_es_runtime_data *data; + struct ghcb *ghcb; + + data = this_cpu_read(runtime_data); + ghcb = &data->ghcb_page; + + if (state->ghcb) { + /* Restore GHCB from Backup */ + *ghcb = *state->ghcb; + data->backup_ghcb_active = false; + state->ghcb = NULL; + } else { + data->ghcb_active = false; + } +} static inline u64 sev_es_rd_ghcb_msr(void) { @@ -332,6 +410,9 @@ static void __init sev_es_init_ghcb(int cpu) panic("Can not map GHCBs unencrypted"); memset(&data->ghcb_page, 0, sizeof(data->ghcb_page)); + + data->ghcb_active = false; + data->backup_ghcb_active = false; } void __init sev_es_init_vc_handling(void) @@ -379,6 +460,148 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt, return result; } +static __always_inline void vc_forward_exception(struct es_em_ctxt *ctxt) +{ + long error_code = ctxt->fi.error_code; + int trapnr = ctxt->fi.vector; + + ctxt->regs->orig_ax = ctxt->fi.error_code; + + switch (trapnr) { + case X86_TRAP_GP: + exc_general_protection(ctxt->regs, error_code); + break; + case X86_TRAP_UD: + exc_invalid_op(ctxt->regs); + break; + default: + pr_emerg("Unsupported exception in #VC instruction emulation - can't continue\n"); + BUG(); + } +} + +static __always_inline bool on_vc_fallback_stack(struct pt_regs *regs) +{ + unsigned long sp = (unsigned long)regs; + + return (sp >= __this_cpu_ist_bot_va(VC2) && sp < __this_cpu_ist_top_va(VC2)); +} + +DEFINE_IDTENTRY_VC_SAFE_STACK(exc_vmm_communication) +{ + struct sev_es_runtime_data *data = this_cpu_read(runtime_data); + struct ghcb_state state; + struct es_em_ctxt ctxt; + enum es_result result; + struct ghcb *ghcb; + + lockdep_assert_irqs_disabled(); + instrumentation_begin(); + + /* + * This is invoked through an interrupt gate, so IRQs are disabled. The + * code below might walk page-tables for user or kernel addresses, so + * keep the IRQs disabled to protect us against concurrent TLB flushes. + */ + + ghcb = sev_es_get_ghcb(&state); + if (!ghcb) { + /* + * Mark GHCBs inactive so that panic() is able to print the + * message. + */ + data->ghcb_active = false; + data->backup_ghcb_active = false; + + panic("Unable to handle #VC exception! GHCB and Backup GHCB are already in use"); + } + + vc_ghcb_invalidate(ghcb); + result = vc_init_em_ctxt(&ctxt, regs, error_code); + + if (result == ES_OK) + result = vc_handle_exitcode(&ctxt, ghcb, error_code); + + sev_es_put_ghcb(&state); + + /* Done - now check the result */ + switch (result) { + case ES_OK: + vc_finish_insn(&ctxt); + break; + case ES_UNSUPPORTED: + pr_err_ratelimited("Unsupported exit-code 0x%02lx in early #VC exception (IP: 0x%lx)\n", + error_code, regs->ip); + goto fail; + case ES_VMM_ERROR: + pr_err_ratelimited("Failure in communication with VMM (exit-code 0x%02lx IP: 0x%lx)\n", + error_code, regs->ip); + goto fail; + case ES_DECODE_FAILED: + pr_err_ratelimited("Failed to decode instruction (exit-code 0x%02lx IP: 0x%lx)\n", + error_code, regs->ip); + goto fail; + case ES_EXCEPTION: + vc_forward_exception(&ctxt); + break; + case ES_RETRY: + /* Nothing to do */ + break; + default: + pr_emerg("Unknown result in %s():%d\n", __func__, result); + /* + * Emulating the instruction which caused the #VC exception + * failed - can't continue so print debug information + */ + BUG(); + } + +out: + instrumentation_end(); + + return; + +fail: + if (user_mode(regs)) { + /* + * Do not kill the machine if user-space triggered the + * exception. Send SIGBUS instead and let user-space deal with + * it. + */ + force_sig_fault(SIGBUS, BUS_OBJERR, (void __user *)0); + } else { + pr_emerg("PANIC: Unhandled #VC exception in kernel space (result=%d)\n", + result); + + /* Show some debug info */ + show_regs(regs); + + /* Ask hypervisor to sev_es_terminate */ + sev_es_terminate(GHCB_SEV_ES_REASON_GENERAL_REQUEST); + + /* If that fails and we get here - just panic */ + panic("Returned from Terminate-Request to Hypervisor\n"); + } + + goto out; +} + +/* This handler runs on the #VC fall-back stack. It can cause further #VC exceptions */ +DEFINE_IDTENTRY_VC_IST(exc_vmm_communication) +{ + instrumentation_begin(); + panic("Can't handle #VC exception from unsupported context\n"); + instrumentation_end(); +} + +DEFINE_IDTENTRY_VC(exc_vmm_communication) +{ + if (likely(!on_vc_fallback_stack(regs))) + safe_stack_exc_vmm_communication(regs, error_code); + else + ist_exc_vmm_communication(regs, error_code); +} + bool __init handle_vc_boot_ghcb(struct pt_regs *regs) { unsigned long exit_code = regs->orig_ax; From patchwork Tue Jul 14 12:08:51 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662587 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B2084618 for ; Tue, 14 Jul 2020 12:13:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A406A22404 for ; Tue, 14 Jul 2020 12:13:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728454AbgGNMLG (ORCPT ); Tue, 14 Jul 2020 08:11:06 -0400 Received: from 8bytes.org ([81.169.241.247]:54106 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728436AbgGNMLE (ORCPT ); Tue, 14 Jul 2020 08:11:04 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 05942FBB; Tue, 14 Jul 2020 14:10:59 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 49/75] x86/sev-es: Wire up existing #VC exit-code handlers Date: Tue, 14 Jul 2020 14:08:51 +0200 Message-Id: <20200714120917.11253-50-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Re-use the handlers for CPUID and IOIO caused #VC exceptions in the early boot handler. Signed-off-by: Joerg Roedel --- arch/x86/kernel/sev-es-shared.c | 7 +++---- arch/x86/kernel/sev-es.c | 6 ++++++ 2 files changed, 9 insertions(+), 4 deletions(-) diff --git a/arch/x86/kernel/sev-es-shared.c b/arch/x86/kernel/sev-es-shared.c index 4153b1b1048f..59884926fae5 100644 --- a/arch/x86/kernel/sev-es-shared.c +++ b/arch/x86/kernel/sev-es-shared.c @@ -325,8 +325,7 @@ static enum es_result vc_ioio_exitinfo(struct es_em_ctxt *ctxt, u64 *exitinfo) return ES_OK; } -static enum es_result __maybe_unused -vc_handle_ioio(struct ghcb *ghcb, struct es_em_ctxt *ctxt) +static enum es_result vc_handle_ioio(struct ghcb *ghcb, struct es_em_ctxt *ctxt) { struct pt_regs *regs = ctxt->regs; u64 exit_info_1, exit_info_2; @@ -434,8 +433,8 @@ vc_handle_ioio(struct ghcb *ghcb, struct es_em_ctxt *ctxt) return ret; } -static enum es_result __maybe_unused vc_handle_cpuid(struct ghcb *ghcb, - struct es_em_ctxt *ctxt) +static enum es_result vc_handle_cpuid(struct ghcb *ghcb, + struct es_em_ctxt *ctxt) { struct pt_regs *regs = ctxt->regs; u32 cr4 = native_read_cr4(); diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index 156914d8e103..e04a1868905b 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -450,6 +450,12 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt, enum es_result result; switch (exit_code) { + case SVM_EXIT_CPUID: + result = vc_handle_cpuid(ghcb, ctxt); + break; + case SVM_EXIT_IOIO: + result = vc_handle_ioio(ghcb, ctxt); + break; default: /* * Unexpected #VC exception From patchwork Tue Jul 14 12:08:52 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662535 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 9D08E618 for ; Tue, 14 Jul 2020 12:11:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8F539222E9 for ; Tue, 14 Jul 2020 12:11:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728470AbgGNMLH (ORCPT ); Tue, 14 Jul 2020 08:11:07 -0400 Received: from 8bytes.org ([81.169.241.247]:54160 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728442AbgGNMLF (ORCPT ); Tue, 14 Jul 2020 08:11:05 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 84AE5FBD; Tue, 14 Jul 2020 14:11:00 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 50/75] x86/sev-es: Handle instruction fetches from user-space Date: Tue, 14 Jul 2020 14:08:52 +0200 Message-Id: <20200714120917.11253-51-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel When a #VC exception is triggered by user-space the instruction decoder needs to read the instruction bytes from user addresses. Enhance vc_decode_insn() to safely fetch kernel and user instructions. Signed-off-by: Joerg Roedel --- arch/x86/kernel/sev-es.c | 31 ++++++++++++++++++++++--------- 1 file changed, 22 insertions(+), 9 deletions(-) diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index e04a1868905b..08b66fd5ae9a 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -247,17 +247,30 @@ static enum es_result vc_decode_insn(struct es_em_ctxt *ctxt) enum es_result ret; int res; - res = vc_fetch_insn_kernel(ctxt, buffer); - if (unlikely(res == -EFAULT)) { - ctxt->fi.vector = X86_TRAP_PF; - ctxt->fi.error_code = 0; - ctxt->fi.cr2 = ctxt->regs->ip; - return ES_EXCEPTION; + if (user_mode(ctxt->regs)) { + res = insn_fetch_from_user(ctxt->regs, buffer); + if (!res) { + ctxt->fi.vector = X86_TRAP_PF; + ctxt->fi.error_code = X86_PF_INSTR | X86_PF_USER; + ctxt->fi.cr2 = ctxt->regs->ip; + return ES_EXCEPTION; + } + + if (!insn_decode(&ctxt->insn, ctxt->regs, buffer, res)) + return ES_DECODE_FAILED; + } else { + res = vc_fetch_insn_kernel(ctxt, buffer); + if (res) { + ctxt->fi.vector = X86_TRAP_PF; + ctxt->fi.error_code = X86_PF_INSTR; + ctxt->fi.cr2 = ctxt->regs->ip; + return ES_EXCEPTION; + } + + insn_init(&ctxt->insn, buffer, MAX_INSN_SIZE - res, 1); + insn_get_length(&ctxt->insn); } - insn_init(&ctxt->insn, buffer, MAX_INSN_SIZE - res, 1); - insn_get_length(&ctxt->insn); - ret = ctxt->insn.immediate.got ? ES_OK : ES_DECODE_FAILED; return ret; From patchwork Tue Jul 14 12:08:53 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662537 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 98EDE618 for ; Tue, 14 Jul 2020 12:11:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 86A6D2231B for ; Tue, 14 Jul 2020 12:11:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728491AbgGNMLJ (ORCPT ); Tue, 14 Jul 2020 08:11:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60704 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728478AbgGNMLH (ORCPT ); Tue, 14 Jul 2020 08:11:07 -0400 Received: from theia.8bytes.org (8bytes.org [IPv6:2a01:238:4383:600:38bc:a715:4b6d:a889]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3C945C061755; Tue, 14 Jul 2020 05:11:07 -0700 (PDT) Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 1C125FBF; Tue, 14 Jul 2020 14:11:01 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , Tom Lendacky , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 51/75] x86/sev-es: Handle MMIO events Date: Tue, 14 Jul 2020 14:08:53 +0200 Message-Id: <20200714120917.11253-52-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Tom Lendacky Add handler for VC exceptions caused by MMIO intercepts. These intercepts come along as nested page faults on pages with reserved bits set. Signed-off-by: Tom Lendacky [ jroedel@suse.de: Adapt to VC handling framework ] Co-developed-by: Joerg Roedel Signed-off-by: Joerg Roedel --- arch/x86/include/uapi/asm/svm.h | 5 + arch/x86/kernel/sev-es.c | 219 ++++++++++++++++++++++++++++++++ 2 files changed, 224 insertions(+) diff --git a/arch/x86/include/uapi/asm/svm.h b/arch/x86/include/uapi/asm/svm.h index c68d1618c9b0..8f36ae021a7f 100644 --- a/arch/x86/include/uapi/asm/svm.h +++ b/arch/x86/include/uapi/asm/svm.h @@ -81,6 +81,11 @@ #define SVM_EXIT_AVIC_INCOMPLETE_IPI 0x401 #define SVM_EXIT_AVIC_UNACCELERATED_ACCESS 0x402 +/* SEV-ES software-defined VMGEXIT events */ +#define SVM_VMGEXIT_MMIO_READ 0x80000001 +#define SVM_VMGEXIT_MMIO_WRITE 0x80000002 +#define SVM_VMGEXIT_UNSUPPORTED_EVENT 0x8000ffff + #define SVM_EXIT_ERR -1 #define SVM_EXIT_REASONS \ diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index 08b66fd5ae9a..44995c3ad17e 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -374,6 +374,36 @@ static enum es_result vc_read_mem(struct es_em_ctxt *ctxt, return ES_EXCEPTION; } +static bool vc_slow_virt_to_phys(struct ghcb *ghcb, struct es_em_ctxt *ctxt, + unsigned long vaddr, phys_addr_t *paddr) +{ + unsigned long va = (unsigned long)vaddr; + unsigned int level; + phys_addr_t pa; + pgd_t *pgd; + pte_t *pte; + + pgd = pgd_offset(current->active_mm, va); + pte = lookup_address_in_pgd(pgd, va, &level); + if (!pte) { + ctxt->fi.vector = X86_TRAP_PF; + ctxt->fi.cr2 = vaddr; + ctxt->fi.error_code = 0; + + if (user_mode(ctxt->regs)) + ctxt->fi.error_code |= X86_PF_USER; + + return false; + } + + pa = (phys_addr_t)pte_pfn(*pte) << PAGE_SHIFT; + pa |= va & ~page_level_mask(level); + + *paddr = pa; + + return true; +} + /* Include code shared with pre-decompression boot stage */ #include "sev-es-shared.c" @@ -456,6 +486,192 @@ static void __init vc_early_forward_exception(struct es_em_ctxt *ctxt) do_early_exception(ctxt->regs, trapnr); } +static long *vc_insn_get_reg(struct es_em_ctxt *ctxt) +{ + long *reg_array; + int offset; + + reg_array = (long *)ctxt->regs; + offset = insn_get_modrm_reg_off(&ctxt->insn, ctxt->regs); + + if (offset < 0) + return NULL; + + offset /= sizeof(long); + + return reg_array + offset; +} + +static enum es_result vc_do_mmio(struct ghcb *ghcb, struct es_em_ctxt *ctxt, + unsigned int bytes, bool read) +{ + u64 exit_code, exit_info_1, exit_info_2; + unsigned long ghcb_pa = __pa(ghcb); + phys_addr_t paddr; + void __user *ref; + + ref = insn_get_addr_ref(&ctxt->insn, ctxt->regs); + if (ref == (void __user *)-1L) + return ES_UNSUPPORTED; + + exit_code = read ? SVM_VMGEXIT_MMIO_READ : SVM_VMGEXIT_MMIO_WRITE; + + if (!vc_slow_virt_to_phys(ghcb, ctxt, (unsigned long)ref, &paddr)) { + if (!read) + ctxt->fi.error_code |= X86_PF_WRITE; + + return ES_EXCEPTION; + } + + exit_info_1 = paddr; + exit_info_2 = bytes; /* Can never be greater than 8 */ + + ghcb->save.sw_scratch = ghcb_pa + offsetof(struct ghcb, shared_buffer); + + return sev_es_ghcb_hv_call(ghcb, ctxt, exit_code, exit_info_1, exit_info_2); +} + +static enum es_result vc_handle_mmio_twobyte_ops(struct ghcb *ghcb, + struct es_em_ctxt *ctxt) +{ + struct insn *insn = &ctxt->insn; + unsigned int bytes = 0; + enum es_result ret; + int sign_byte; + long *reg_data; + + switch (insn->opcode.bytes[1]) { + /* MMIO Read w/ zero-extension */ + case 0xb6: + bytes = 1; + fallthrough; + case 0xb7: + if (!bytes) + bytes = 2; + + ret = vc_do_mmio(ghcb, ctxt, bytes, true); + if (ret) + break; + + /* Zero extend based on operand size */ + reg_data = vc_insn_get_reg(ctxt); + if (!reg_data) + return ES_DECODE_FAILED; + + memset(reg_data, 0, insn->opnd_bytes); + + memcpy(reg_data, ghcb->shared_buffer, bytes); + break; + + /* MMIO Read w/ sign-extension */ + case 0xbe: + bytes = 1; + fallthrough; + case 0xbf: + if (!bytes) + bytes = 2; + + ret = vc_do_mmio(ghcb, ctxt, bytes, true); + if (ret) + break; + + /* Sign extend based on operand size */ + reg_data = vc_insn_get_reg(ctxt); + if (!reg_data) + return ES_DECODE_FAILED; + + if (bytes == 1) { + u8 *val = (u8 *)ghcb->shared_buffer; + + sign_byte = (*val & 0x80) ? 0xff : 0x00; + } else { + u16 *val = (u16 *)ghcb->shared_buffer; + + sign_byte = (*val & 0x8000) ? 0xff : 0x00; + } + memset(reg_data, sign_byte, insn->opnd_bytes); + + memcpy(reg_data, ghcb->shared_buffer, bytes); + break; + + default: + ret = ES_UNSUPPORTED; + } + + return ret; +} + +static enum es_result vc_handle_mmio(struct ghcb *ghcb, + struct es_em_ctxt *ctxt) +{ + struct insn *insn = &ctxt->insn; + unsigned int bytes = 0; + enum es_result ret; + long *reg_data; + + switch (insn->opcode.bytes[0]) { + /* MMIO Write */ + case 0x88: + bytes = 1; + fallthrough; + case 0x89: + if (!bytes) + bytes = insn->opnd_bytes; + + reg_data = vc_insn_get_reg(ctxt); + if (!reg_data) + return ES_DECODE_FAILED; + + memcpy(ghcb->shared_buffer, reg_data, bytes); + + ret = vc_do_mmio(ghcb, ctxt, bytes, false); + break; + + case 0xc6: + bytes = 1; + fallthrough; + case 0xc7: + if (!bytes) + bytes = insn->opnd_bytes; + + memcpy(ghcb->shared_buffer, insn->immediate1.bytes, bytes); + + ret = vc_do_mmio(ghcb, ctxt, bytes, false); + break; + + /* MMIO Read */ + case 0x8a: + bytes = 1; + fallthrough; + case 0x8b: + if (!bytes) + bytes = insn->opnd_bytes; + + ret = vc_do_mmio(ghcb, ctxt, bytes, true); + if (ret) + break; + + reg_data = vc_insn_get_reg(ctxt); + if (!reg_data) + return ES_DECODE_FAILED; + + if (bytes == 4) + *reg_data = 0; /* Zero-extend for 32-bit operation */ + + memcpy(reg_data, ghcb->shared_buffer, bytes); + break; + + /* Two-Byte Opcodes */ + case 0x0f: + ret = vc_handle_mmio_twobyte_ops(ghcb, ctxt); + break; + default: + ret = ES_UNSUPPORTED; + } + + return ret; +} + static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt, struct ghcb *ghcb, unsigned long exit_code) @@ -469,6 +685,9 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt, case SVM_EXIT_IOIO: result = vc_handle_ioio(ghcb, ctxt); break; + case SVM_EXIT_NPF: + result = vc_handle_mmio(ghcb, ctxt); + break; default: /* * Unexpected #VC exception From patchwork Tue Jul 14 12:08:54 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662585 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 83F2813B4 for ; Tue, 14 Jul 2020 12:13:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 74D1E2236F for ; Tue, 14 Jul 2020 12:13:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728873AbgGNMNi (ORCPT ); Tue, 14 Jul 2020 08:13:38 -0400 Received: from 8bytes.org ([81.169.241.247]:52886 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728444AbgGNMLH (ORCPT ); Tue, 14 Jul 2020 08:11:07 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 9B050FC0; Tue, 14 Jul 2020 14:11:01 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 52/75] x86/sev-es: Handle MMIO String Instructions Date: Tue, 14 Jul 2020 14:08:54 +0200 Message-Id: <20200714120917.11253-53-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Add handling for emulation the MOVS instruction on MMIO regions, as done by the memcpy_toio() and memcpy_fromio() functions. Signed-off-by: Joerg Roedel --- arch/x86/kernel/sev-es.c | 77 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 77 insertions(+) diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index 44995c3ad17e..bbd839a9d9a1 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -601,6 +601,73 @@ static enum es_result vc_handle_mmio_twobyte_ops(struct ghcb *ghcb, return ret; } +/* + * The MOVS instruction has two memory operands, which raises the + * problem that it is not known whether the access to the source or the + * destination caused the #VC exception (and hence whether an MMIO read + * or write operation needs to be emulated). + * + * Instead of playing games with walking page-tables and trying to guess + * whether the source or destination is an MMIO range, split the move + * into two operations, a read and a write with only one memory operand. + * This will cause a nested #VC exception on the MMIO address which can + * then be handled. + * + * This implementation has the benefit that it also supports MOVS where + * source _and_ destination are MMIO regions. + * + * It will slow MOVS on MMIO down a lot, but in SEV-ES guests it is a + * rare operation. If it turns out to be a performance problem the split + * operations can be moved to memcpy_fromio() and memcpy_toio(). + */ +static enum es_result vc_handle_mmio_movs(struct es_em_ctxt *ctxt, + unsigned int bytes) +{ + unsigned long ds_base, es_base; + unsigned char *src, *dst; + unsigned char buffer[8]; + enum es_result ret; + bool rep; + int off; + + ds_base = insn_get_seg_base(ctxt->regs, INAT_SEG_REG_DS); + es_base = insn_get_seg_base(ctxt->regs, INAT_SEG_REG_ES); + + if (ds_base == -1L || es_base == -1L) { + ctxt->fi.vector = X86_TRAP_GP; + ctxt->fi.error_code = 0; + return ES_EXCEPTION; + } + + src = ds_base + (unsigned char *)ctxt->regs->si; + dst = es_base + (unsigned char *)ctxt->regs->di; + + ret = vc_read_mem(ctxt, src, buffer, bytes); + if (ret != ES_OK) + return ret; + + ret = vc_write_mem(ctxt, dst, buffer, bytes); + if (ret != ES_OK) + return ret; + + if (ctxt->regs->flags & X86_EFLAGS_DF) + off = -bytes; + else + off = bytes; + + ctxt->regs->si += off; + ctxt->regs->di += off; + + rep = insn_has_rep_prefix(&ctxt->insn); + if (rep) + ctxt->regs->cx -= 1; + + if (!rep || ctxt->regs->cx == 0) + return ES_OK; + else + return ES_RETRY; +} + static enum es_result vc_handle_mmio(struct ghcb *ghcb, struct es_em_ctxt *ctxt) { @@ -661,6 +728,16 @@ static enum es_result vc_handle_mmio(struct ghcb *ghcb, memcpy(reg_data, ghcb->shared_buffer, bytes); break; + /* MOVS instruction */ + case 0xa4: + bytes = 1; + fallthrough; + case 0xa5: + if (!bytes) + bytes = insn->opnd_bytes; + + ret = vc_handle_mmio_movs(ctxt, bytes); + break; /* Two-Byte Opcodes */ case 0x0f: ret = vc_handle_mmio_twobyte_ops(ghcb, ctxt); From patchwork Tue Jul 14 12:08:55 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662583 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 38C8C13B4 for ; Tue, 14 Jul 2020 12:13:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1F60B223C6 for ; Tue, 14 Jul 2020 12:13:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728878AbgGNMNb (ORCPT ); Tue, 14 Jul 2020 08:13:31 -0400 Received: from 8bytes.org ([81.169.241.247]:53376 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728467AbgGNMLI (ORCPT ); Tue, 14 Jul 2020 08:11:08 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 3E292FC1; Tue, 14 Jul 2020 14:11:02 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , Tom Lendacky , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 53/75] x86/sev-es: Handle MSR events Date: Tue, 14 Jul 2020 14:08:55 +0200 Message-Id: <20200714120917.11253-54-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Tom Lendacky Implement a handler for #VC exceptions caused by RDMSR/WRMSR instructions. Signed-off-by: Tom Lendacky [ jroedel@suse.de: Adapt to #VC handling infrastructure ] Co-developed-by: Joerg Roedel Signed-off-by: Joerg Roedel --- arch/x86/kernel/sev-es.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index bbd839a9d9a1..cbe158091f18 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -407,6 +407,31 @@ static bool vc_slow_virt_to_phys(struct ghcb *ghcb, struct es_em_ctxt *ctxt, /* Include code shared with pre-decompression boot stage */ #include "sev-es-shared.c" +static enum es_result vc_handle_msr(struct ghcb *ghcb, struct es_em_ctxt *ctxt) +{ + struct pt_regs *regs = ctxt->regs; + enum es_result ret; + u64 exit_info_1; + + /* Is it a WRMSR? */ + exit_info_1 = (ctxt->insn.opcode.bytes[1] == 0x30) ? 1 : 0; + + ghcb_set_rcx(ghcb, regs->cx); + if (exit_info_1) { + ghcb_set_rax(ghcb, regs->ax); + ghcb_set_rdx(ghcb, regs->dx); + } + + ret = sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_MSR, exit_info_1, 0); + + if ((ret == ES_OK) && (!exit_info_1)) { + regs->ax = ghcb->save.rax; + regs->dx = ghcb->save.rdx; + } + + return ret; +} + /* * This function runs on the first #VC exception after the kernel * switched to virtual addresses. @@ -762,6 +787,9 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt, case SVM_EXIT_IOIO: result = vc_handle_ioio(ghcb, ctxt); break; + case SVM_EXIT_MSR: + result = vc_handle_msr(ghcb, ctxt); + break; case SVM_EXIT_NPF: result = vc_handle_mmio(ghcb, ctxt); break; From patchwork Tue Jul 14 12:08:56 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662581 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E8F4A13B4 for ; Tue, 14 Jul 2020 12:13:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DAD3D2236F for ; Tue, 14 Jul 2020 12:13:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728850AbgGNMNZ (ORCPT ); Tue, 14 Jul 2020 08:13:25 -0400 Received: from 8bytes.org ([81.169.241.247]:52886 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728480AbgGNMLI (ORCPT ); Tue, 14 Jul 2020 08:11:08 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id DDB69FC2; Tue, 14 Jul 2020 14:11:02 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , Tom Lendacky , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 54/75] x86/sev-es: Handle DR7 read/write events Date: Tue, 14 Jul 2020 14:08:56 +0200 Message-Id: <20200714120917.11253-55-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Tom Lendacky Add code to handle #VC exceptions on DR7 register reads and writes. This is needed early because show_regs() reads DR7 to print it out. Under SEV-ES there is currently no support for saving/restoring the DRx registers, but software expects to be able to write to the DR7 register. For now, cache the value written to DR7 and return it on read attempts, but do not touch the real hardware DR7. Signed-off-by: Tom Lendacky [ jroedel@suse.de: - Adapt to #VC handling framework - Support early usage ] Co-developed-by: Joerg Roedel Signed-off-by: Joerg Roedel --- arch/x86/kernel/sev-es.c | 85 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 85 insertions(+) diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index cbe158091f18..09738d6fe55e 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -28,6 +28,8 @@ #include #include +#define DR7_RESET_VALUE 0x400 + /* For early boot hypervisor communication in SEV-ES enabled guests */ static struct ghcb boot_ghcb_page __bss_decrypted __aligned(PAGE_SIZE); @@ -75,6 +77,13 @@ struct sev_es_runtime_data { */ bool ghcb_active; bool backup_ghcb_active; + + /* + * Cached DR7 value - write it on DR7 writes and return it on reads. + * That value will never make it to the real hardware DR7 as debugging + * is currently unsupported in SEV-ES guests. + */ + unsigned long dr7; }; struct ghcb_state { @@ -527,6 +536,21 @@ static long *vc_insn_get_reg(struct es_em_ctxt *ctxt) return reg_array + offset; } +static long *vc_insn_get_rm(struct es_em_ctxt *ctxt) +{ + long *reg_array; + int offset; + + reg_array = (long *)ctxt->regs; + offset = insn_get_modrm_rm_off(&ctxt->insn, ctxt->regs); + + if (offset < 0) + return NULL; + + offset /= sizeof(long); + + return reg_array + offset; +} static enum es_result vc_do_mmio(struct ghcb *ghcb, struct es_em_ctxt *ctxt, unsigned int bytes, bool read) { @@ -774,6 +798,61 @@ static enum es_result vc_handle_mmio(struct ghcb *ghcb, return ret; } +static enum es_result vc_handle_dr7_write(struct ghcb *ghcb, + struct es_em_ctxt *ctxt) +{ + struct sev_es_runtime_data *data = this_cpu_read(runtime_data); + long val, *reg = vc_insn_get_rm(ctxt); + enum es_result ret; + + if (!reg) + return ES_DECODE_FAILED; + + val = *reg; + + /* Upper 32 bits must be written as zeroes */ + if (val >> 32) { + ctxt->fi.vector = X86_TRAP_GP; + ctxt->fi.error_code = 0; + return ES_EXCEPTION; + } + + /* Clear out other reserved bits and set bit 10 */ + val = (val & 0xffff23ffL) | BIT(10); + + /* Early non-zero writes to DR7 are not supported */ + if (!data && (val & ~DR7_RESET_VALUE)) + return ES_UNSUPPORTED; + + /* Using a value of 0 for ExitInfo1 means RAX holds the value */ + ghcb_set_rax(ghcb, val); + ret = sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_WRITE_DR7, 0, 0); + if (ret != ES_OK) + return ret; + + if (data) + data->dr7 = val; + + return ES_OK; +} + +static enum es_result vc_handle_dr7_read(struct ghcb *ghcb, + struct es_em_ctxt *ctxt) +{ + struct sev_es_runtime_data *data = this_cpu_read(runtime_data); + long *reg = vc_insn_get_rm(ctxt); + + if (!reg) + return ES_DECODE_FAILED; + + if (data) + *reg = data->dr7; + else + *reg = DR7_RESET_VALUE; + + return ES_OK; +} + static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt, struct ghcb *ghcb, unsigned long exit_code) @@ -781,6 +860,12 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt, enum es_result result; switch (exit_code) { + case SVM_EXIT_READ_DR7: + result = vc_handle_dr7_read(ghcb, ctxt); + break; + case SVM_EXIT_WRITE_DR7: + result = vc_handle_dr7_write(ghcb, ctxt); + break; case SVM_EXIT_CPUID: result = vc_handle_cpuid(ghcb, ctxt); break; From patchwork Tue Jul 14 12:08:57 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662541 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 87D8614DD for ; Tue, 14 Jul 2020 12:11:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6F7F7223BE for ; Tue, 14 Jul 2020 12:11:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728525AbgGNMLM (ORCPT ); Tue, 14 Jul 2020 08:11:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60712 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728502AbgGNMLL (ORCPT ); Tue, 14 Jul 2020 08:11:11 -0400 Received: from theia.8bytes.org (8bytes.org [IPv6:2a01:238:4383:600:38bc:a715:4b6d:a889]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BE26CC061755; Tue, 14 Jul 2020 05:11:10 -0700 (PDT) Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 696DFFC3; Tue, 14 Jul 2020 14:11:03 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , Tom Lendacky , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 55/75] x86/sev-es: Handle WBINVD Events Date: Tue, 14 Jul 2020 14:08:57 +0200 Message-Id: <20200714120917.11253-56-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Tom Lendacky Implement a handler for #VC exceptions caused by WBINVD instructions. Signed-off-by: Tom Lendacky [ jroedel@suse.de: Adapt to #VC handling framework ] Co-developed-by: Joerg Roedel Signed-off-by: Joerg Roedel --- arch/x86/kernel/sev-es.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index 09738d6fe55e..aa117004fc2e 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -853,6 +853,12 @@ static enum es_result vc_handle_dr7_read(struct ghcb *ghcb, return ES_OK; } +static enum es_result vc_handle_wbinvd(struct ghcb *ghcb, + struct es_em_ctxt *ctxt) +{ + return sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_WBINVD, 0, 0); +} + static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt, struct ghcb *ghcb, unsigned long exit_code) @@ -875,6 +881,9 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt, case SVM_EXIT_MSR: result = vc_handle_msr(ghcb, ctxt); break; + case SVM_EXIT_WBINVD: + result = vc_handle_wbinvd(ghcb, ctxt); + break; case SVM_EXIT_NPF: result = vc_handle_mmio(ghcb, ctxt); break; From patchwork Tue Jul 14 12:08:58 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662539 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E148E13B4 for ; Tue, 14 Jul 2020 12:11:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D3B33222E9 for ; Tue, 14 Jul 2020 12:11:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728509AbgGNMLL (ORCPT ); Tue, 14 Jul 2020 08:11:11 -0400 Received: from 8bytes.org ([81.169.241.247]:53376 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728494AbgGNMLK (ORCPT ); Tue, 14 Jul 2020 08:11:10 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 0199BFC6; Tue, 14 Jul 2020 14:11:03 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , Tom Lendacky , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 56/75] x86/sev-es: Handle RDTSC(P) Events Date: Tue, 14 Jul 2020 14:08:58 +0200 Message-Id: <20200714120917.11253-57-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Tom Lendacky Implement a handler for #VC exceptions caused by RDTSC and RDTSCP instructions. Also make it available in the pre-decompression stage because the KASLR code used RDTSC/RDTSCP to gather entropy and some hypervisors intercept these instructions. Signed-off-by: Tom Lendacky [ jroedel@suse.de: - Adapt to #VC handling infrastructure - Make it available early ] Co-developed-by: Joerg Roedel Signed-off-by: Joerg Roedel --- arch/x86/boot/compressed/sev-es.c | 4 ++++ arch/x86/kernel/sev-es-shared.c | 23 +++++++++++++++++++++++ arch/x86/kernel/sev-es.c | 4 ++++ 3 files changed, 31 insertions(+) diff --git a/arch/x86/boot/compressed/sev-es.c b/arch/x86/boot/compressed/sev-es.c index 851d7af29d79..1ce144e0ddc3 100644 --- a/arch/x86/boot/compressed/sev-es.c +++ b/arch/x86/boot/compressed/sev-es.c @@ -181,6 +181,10 @@ void do_boot_stage2_vc(struct pt_regs *regs, unsigned long exit_code) goto finish; switch (exit_code) { + case SVM_EXIT_RDTSC: + case SVM_EXIT_RDTSCP: + result = vc_handle_rdtsc(boot_ghcb, &ctxt, exit_code); + break; case SVM_EXIT_IOIO: result = vc_handle_ioio(boot_ghcb, &ctxt); break; diff --git a/arch/x86/kernel/sev-es-shared.c b/arch/x86/kernel/sev-es-shared.c index 59884926fae5..608f76d0d088 100644 --- a/arch/x86/kernel/sev-es-shared.c +++ b/arch/x86/kernel/sev-es-shared.c @@ -467,3 +467,26 @@ static enum es_result vc_handle_cpuid(struct ghcb *ghcb, return ES_OK; } + +static enum es_result vc_handle_rdtsc(struct ghcb *ghcb, + struct es_em_ctxt *ctxt, + unsigned long exit_code) +{ + bool rdtscp = (exit_code == SVM_EXIT_RDTSCP); + enum es_result ret; + + ret = sev_es_ghcb_hv_call(ghcb, ctxt, exit_code, 0, 0); + if (ret != ES_OK) + return ret; + + if (!(ghcb_is_valid_rax(ghcb) && ghcb_is_valid_rdx(ghcb) && + (!rdtscp || ghcb_is_valid_rcx(ghcb)))) + return ES_VMM_ERROR; + + ctxt->regs->ax = ghcb->save.rax; + ctxt->regs->dx = ghcb->save.rdx; + if (rdtscp) + ctxt->regs->cx = ghcb->save.rcx; + + return ES_OK; +} diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index aa117004fc2e..0e69d498f008 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -872,6 +872,10 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt, case SVM_EXIT_WRITE_DR7: result = vc_handle_dr7_write(ghcb, ctxt); break; + case SVM_EXIT_RDTSC: + case SVM_EXIT_RDTSCP: + result = vc_handle_rdtsc(ghcb, ctxt, exit_code); + break; case SVM_EXIT_CPUID: result = vc_handle_cpuid(ghcb, ctxt); break; From patchwork Tue Jul 14 12:08:59 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662579 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 42828618 for ; Tue, 14 Jul 2020 12:13:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2A46B2242E for ; Tue, 14 Jul 2020 12:13:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728845AbgGNMNP (ORCPT ); Tue, 14 Jul 2020 08:13:15 -0400 Received: from 8bytes.org ([81.169.241.247]:52886 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728500AbgGNMLL (ORCPT ); Tue, 14 Jul 2020 08:11:11 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 934E7FC8; Tue, 14 Jul 2020 14:11:04 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , Tom Lendacky , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 57/75] x86/sev-es: Handle RDPMC Events Date: Tue, 14 Jul 2020 14:08:59 +0200 Message-Id: <20200714120917.11253-58-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Tom Lendacky Implement a handler for #VC exceptions caused by RDPMC instructions. Signed-off-by: Tom Lendacky [ jroedel@suse.de: Adapt to #VC handling infrastructure ] Co-developed-by: Joerg Roedel Signed-off-by: Joerg Roedel --- arch/x86/kernel/sev-es.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index 0e69d498f008..6258bc8074fd 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -859,6 +859,25 @@ static enum es_result vc_handle_wbinvd(struct ghcb *ghcb, return sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_WBINVD, 0, 0); } +static enum es_result vc_handle_rdpmc(struct ghcb *ghcb, struct es_em_ctxt *ctxt) +{ + enum es_result ret; + + ghcb_set_rcx(ghcb, ctxt->regs->cx); + + ret = sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_RDPMC, 0, 0); + if (ret != ES_OK) + return ret; + + if (!(ghcb_is_valid_rax(ghcb) && ghcb_is_valid_rdx(ghcb))) + return ES_VMM_ERROR; + + ctxt->regs->ax = ghcb->save.rax; + ctxt->regs->dx = ghcb->save.rdx; + + return ES_OK; +} + static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt, struct ghcb *ghcb, unsigned long exit_code) @@ -876,6 +895,9 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt, case SVM_EXIT_RDTSCP: result = vc_handle_rdtsc(ghcb, ctxt, exit_code); break; + case SVM_EXIT_RDPMC: + result = vc_handle_rdpmc(ghcb, ctxt); + break; case SVM_EXIT_CPUID: result = vc_handle_cpuid(ghcb, ctxt); break; From patchwork Tue Jul 14 12:09:00 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662575 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id CBDDD618 for ; Tue, 14 Jul 2020 12:12:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B3082223C6 for ; Tue, 14 Jul 2020 12:12:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728527AbgGNMMv (ORCPT ); Tue, 14 Jul 2020 08:12:51 -0400 Received: from 8bytes.org ([81.169.241.247]:53376 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728515AbgGNMLM (ORCPT ); Tue, 14 Jul 2020 08:11:12 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 255EFFCE; Tue, 14 Jul 2020 14:11:05 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , Tom Lendacky , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 58/75] x86/sev-es: Handle INVD Events Date: Tue, 14 Jul 2020 14:09:00 +0200 Message-Id: <20200714120917.11253-59-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Tom Lendacky Implement a handler for #VC exceptions caused by INVD instructions. Since Linux should never use INVD, just mark it as unsupported. Signed-off-by: Tom Lendacky [ jroedel@suse.de: Adapt to #VC handling infrastructure ] Co-developed-by: Joerg Roedel Signed-off-by: Joerg Roedel --- arch/x86/kernel/sev-es.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index 6258bc8074fd..30d6161deada 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -898,6 +898,10 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt, case SVM_EXIT_RDPMC: result = vc_handle_rdpmc(ghcb, ctxt); break; + case SVM_EXIT_INVD: + pr_err_ratelimited("#VC exception for INVD??? Seriously???\n"); + result = ES_UNSUPPORTED; + break; case SVM_EXIT_CPUID: result = vc_handle_cpuid(ghcb, ctxt); break; From patchwork Tue Jul 14 12:09:01 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662577 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 6A0C413B4 for ; Tue, 14 Jul 2020 12:13:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5B132222D9 for ; Tue, 14 Jul 2020 12:13:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728619AbgGNMMt (ORCPT ); Tue, 14 Jul 2020 08:12:49 -0400 Received: from 8bytes.org ([81.169.241.247]:54446 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728527AbgGNMLN (ORCPT ); Tue, 14 Jul 2020 08:11:13 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id A6713FD1; Tue, 14 Jul 2020 14:11:05 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , Tom Lendacky , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 59/75] x86/sev-es: Handle MONITOR/MONITORX Events Date: Tue, 14 Jul 2020 14:09:01 +0200 Message-Id: <20200714120917.11253-60-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Tom Lendacky Implement a handler for #VC exceptions caused by MONITOR and MONITORX instructions. Signed-off-by: Tom Lendacky [ jroedel@suse.de: Adapt to #VC handling infrastructure ] Co-developed-by: Joerg Roedel Signed-off-by: Joerg Roedel --- arch/x86/kernel/sev-es.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index 30d6161deada..c0977bdc400e 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -878,6 +878,16 @@ static enum es_result vc_handle_rdpmc(struct ghcb *ghcb, struct es_em_ctxt *ctxt return ES_OK; } +static enum es_result vc_handle_monitor(struct ghcb *ghcb, + struct es_em_ctxt *ctxt) +{ + /* + * Treat it as a NOP and do not leak a physical address to the + * hypervisor + */ + return ES_OK; +} + static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt, struct ghcb *ghcb, unsigned long exit_code) @@ -914,6 +924,9 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt, case SVM_EXIT_WBINVD: result = vc_handle_wbinvd(ghcb, ctxt); break; + case SVM_EXIT_MONITOR: + result = vc_handle_monitor(ghcb, ctxt); + break; case SVM_EXIT_NPF: result = vc_handle_mmio(ghcb, ctxt); break; From patchwork Tue Jul 14 12:09:02 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662573 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 3A9F913B4 for ; Tue, 14 Jul 2020 12:12:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 20410222D9 for ; Tue, 14 Jul 2020 12:12:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728816AbgGNMMu (ORCPT ); Tue, 14 Jul 2020 08:12:50 -0400 Received: from 8bytes.org ([81.169.241.247]:52886 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728530AbgGNMLN (ORCPT ); Tue, 14 Jul 2020 08:11:13 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 33239FD7; Tue, 14 Jul 2020 14:11:06 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , Tom Lendacky , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 60/75] x86/sev-es: Handle MWAIT/MWAITX Events Date: Tue, 14 Jul 2020 14:09:02 +0200 Message-Id: <20200714120917.11253-61-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Tom Lendacky Implement a handler for #VC exceptions caused by MWAIT and MWAITX instructions. Signed-off-by: Tom Lendacky [ jroedel@suse.de: Adapt to #VC handling infrastructure ] Co-developed-by: Joerg Roedel Signed-off-by: Joerg Roedel --- arch/x86/kernel/sev-es.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index c0977bdc400e..541f8994eb21 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -888,6 +888,13 @@ static enum es_result vc_handle_monitor(struct ghcb *ghcb, return ES_OK; } +static enum es_result vc_handle_mwait(struct ghcb *ghcb, + struct es_em_ctxt *ctxt) +{ + /* Treat the same as MONITOR/MONITORX */ + return ES_OK; +} + static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt, struct ghcb *ghcb, unsigned long exit_code) @@ -927,6 +934,9 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt, case SVM_EXIT_MONITOR: result = vc_handle_monitor(ghcb, ctxt); break; + case SVM_EXIT_MWAIT: + result = vc_handle_mwait(ghcb, ctxt); + break; case SVM_EXIT_NPF: result = vc_handle_mmio(ghcb, ctxt); break; From patchwork Tue Jul 14 12:09:03 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662565 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id D2649618 for ; Tue, 14 Jul 2020 12:12:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BAD19222B6 for ; Tue, 14 Jul 2020 12:12:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728565AbgGNMLS (ORCPT ); Tue, 14 Jul 2020 08:11:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60730 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728541AbgGNMLQ (ORCPT ); Tue, 14 Jul 2020 08:11:16 -0400 Received: from theia.8bytes.org (8bytes.org [IPv6:2a01:238:4383:600:38bc:a715:4b6d:a889]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 40E4DC061755; Tue, 14 Jul 2020 05:11:16 -0700 (PDT) Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id BBDEEFD9; Tue, 14 Jul 2020 14:11:06 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , Tom Lendacky , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 61/75] x86/sev-es: Handle VMMCALL Events Date: Tue, 14 Jul 2020 14:09:03 +0200 Message-Id: <20200714120917.11253-62-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Tom Lendacky Implement a handler for #VC exceptions caused by VMMCALL instructions. This patch is only a starting point, VMMCALL emulation under SEV-ES needs further hypervisor-specific changes to provide additional state. Signed-off-by: Tom Lendacky [ jroedel@suse.de: Adapt to #VC handling infrastructure ] Co-developed-by: Joerg Roedel Signed-off-by: Joerg Roedel --- arch/x86/kernel/sev-es.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index 541f8994eb21..013dcdfeb613 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -895,6 +895,26 @@ static enum es_result vc_handle_mwait(struct ghcb *ghcb, return ES_OK; } +static enum es_result vc_handle_vmmcall(struct ghcb *ghcb, + struct es_em_ctxt *ctxt) +{ + enum es_result ret; + + ghcb_set_rax(ghcb, ctxt->regs->ax); + ghcb_set_cpl(ghcb, user_mode(ctxt->regs) ? 3 : 0); + + ret = sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_VMMCALL, 0, 0); + if (ret != ES_OK) + return ret; + + if (!ghcb_is_valid_rax(ghcb)) + return ES_VMM_ERROR; + + ctxt->regs->ax = ghcb->save.rax; + + return ES_OK; +} + static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt, struct ghcb *ghcb, unsigned long exit_code) @@ -928,6 +948,9 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt, case SVM_EXIT_MSR: result = vc_handle_msr(ghcb, ctxt); break; + case SVM_EXIT_VMMCALL: + result = vc_handle_vmmcall(ghcb, ctxt); + break; case SVM_EXIT_WBINVD: result = vc_handle_wbinvd(ghcb, ctxt); break; From patchwork Tue Jul 14 12:09:04 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662571 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 256EA13B4 for ; Tue, 14 Jul 2020 12:12:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0BDF1222D9 for ; Tue, 14 Jul 2020 12:12:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728800AbgGNMMn (ORCPT ); Tue, 14 Jul 2020 08:12:43 -0400 Received: from 8bytes.org ([81.169.241.247]:52886 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728513AbgGNMLP (ORCPT ); Tue, 14 Jul 2020 08:11:15 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 4263CFDC; Tue, 14 Jul 2020 14:11:07 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 62/75] x86/sev-es: Handle #AC Events Date: Tue, 14 Jul 2020 14:09:04 +0200 Message-Id: <20200714120917.11253-63-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Implement a handler for #VC exceptions caused by #AC exceptions. The #AC exception is just forwarded to do_alignment_check() and not pushed down to the hypervisor, as requested by the SEV-ES GHCB Standardization Specification. Signed-off-by: Joerg Roedel --- arch/x86/kernel/sev-es.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index 013dcdfeb613..8f275e5d1ce7 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -915,6 +915,19 @@ static enum es_result vc_handle_vmmcall(struct ghcb *ghcb, return ES_OK; } +static enum es_result vc_handle_trap_ac(struct ghcb *ghcb, + struct es_em_ctxt *ctxt) +{ + /* + * Calling ecx_alignment_check() directly does not work, because it + * enables IRQs and the GHCB is active. Forward the exception and call + * it later from vc_forward_exception(). + */ + ctxt->fi.vector = X86_TRAP_AC; + ctxt->fi.error_code = 0; + return ES_EXCEPTION; +} + static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt, struct ghcb *ghcb, unsigned long exit_code) @@ -928,6 +941,9 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt, case SVM_EXIT_WRITE_DR7: result = vc_handle_dr7_write(ghcb, ctxt); break; + case SVM_EXIT_EXCP_BASE + X86_TRAP_AC: + result = vc_handle_trap_ac(ghcb, ctxt); + break; case SVM_EXIT_RDTSC: case SVM_EXIT_RDTSCP: result = vc_handle_rdtsc(ghcb, ctxt, exit_code); @@ -987,6 +1003,9 @@ static __always_inline void vc_forward_exception(struct es_em_ctxt *ctxt) case X86_TRAP_UD: exc_invalid_op(ctxt->regs); break; + case X86_TRAP_AC: + exc_alignment_check(ctxt->regs, error_code); + break; default: pr_emerg("Unsupported exception in #VC instruction emulation - can't continue\n"); BUG(); From patchwork Tue Jul 14 12:09:05 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662543 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 394BC13B4 for ; Tue, 14 Jul 2020 12:11:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 279CC223AE for ; Tue, 14 Jul 2020 12:11:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728588AbgGNMLT (ORCPT ); Tue, 14 Jul 2020 08:11:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60734 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728553AbgGNMLR (ORCPT ); Tue, 14 Jul 2020 08:11:17 -0400 Received: from theia.8bytes.org (8bytes.org [IPv6:2a01:238:4383:600:38bc:a715:4b6d:a889]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 85CF8C061755; Tue, 14 Jul 2020 05:11:17 -0700 (PDT) Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id C5E67FDD; Tue, 14 Jul 2020 14:11:07 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 63/75] x86/sev-es: Handle #DB Events Date: Tue, 14 Jul 2020 14:09:05 +0200 Message-Id: <20200714120917.11253-64-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Handle #VC exceptions caused by #DB exceptions in the guest. Those must be handled outside of instrumentation_begin()/end() so that the handler will not be raised recursivly. Handle them by calling the kernels debug exception handler. Signed-off-by: Joerg Roedel --- arch/x86/kernel/sev-es.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index 8f275e5d1ce7..b0f08d9669f1 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -928,6 +928,14 @@ static enum es_result vc_handle_trap_ac(struct ghcb *ghcb, return ES_EXCEPTION; } +static __always_inline void vc_handle_trap_db(struct pt_regs *regs) +{ + if (user_mode(regs)) + noist_exc_debug(regs); + else + exc_debug(regs); +} + static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt, struct ghcb *ghcb, unsigned long exit_code) @@ -1028,6 +1036,16 @@ DEFINE_IDTENTRY_VC_SAFE_STACK(exc_vmm_communication) struct ghcb *ghcb; lockdep_assert_irqs_disabled(); + + /* + * #DB is special and needs to be handled outside of the intrumentation_begin()/end(). + * Otherwise the #VC handler could be raised recursivly. + */ + if (error_code == SVM_EXIT_EXCP_BASE + X86_TRAP_DB) { + vc_handle_trap_db(regs); + return; + } + instrumentation_begin(); /* From patchwork Tue Jul 14 12:09:06 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662567 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 14BB7618 for ; Tue, 14 Jul 2020 12:12:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 075142245B for ; Tue, 14 Jul 2020 12:12:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728732AbgGNMMb (ORCPT ); Tue, 14 Jul 2020 08:12:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60738 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728575AbgGNMLS (ORCPT ); Tue, 14 Jul 2020 08:11:18 -0400 Received: from theia.8bytes.org (8bytes.org [IPv6:2a01:238:4383:600:38bc:a715:4b6d:a889]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 53AC6C061755; Tue, 14 Jul 2020 05:11:18 -0700 (PDT) Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 61DA3FDE; Tue, 14 Jul 2020 14:11:08 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 64/75] x86/paravirt: Allow hypervisor specific VMMCALL handling under SEV-ES Date: Tue, 14 Jul 2020 14:09:06 +0200 Message-Id: <20200714120917.11253-65-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Add two new paravirt callbacks to provide hypervisor specific processor state in the GHCB and to copy state from the hypervisor back to the processor. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/x86_init.h | 16 +++++++++++++++- arch/x86/kernel/sev-es.c | 12 ++++++++++++ 2 files changed, 27 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/x86_init.h b/arch/x86/include/asm/x86_init.h index 6807153c0410..0304e2931cd3 100644 --- a/arch/x86/include/asm/x86_init.h +++ b/arch/x86/include/asm/x86_init.h @@ -4,8 +4,10 @@ #include +struct ghcb; struct mpc_bus; struct mpc_cpu; +struct pt_regs; struct mpc_table; struct cpuinfo_x86; @@ -236,10 +238,22 @@ struct x86_legacy_features { /** * struct x86_hyper_runtime - x86 hypervisor specific runtime callbacks * - * @pin_vcpu: pin current vcpu to specified physical cpu (run rarely) + * @pin_vcpu: pin current vcpu to specified physical + * cpu (run rarely) + * @sev_es_hcall_prepare: Load additional hypervisor-specific + * state into the GHCB when doing a VMMCALL under + * SEV-ES. Called from the #VC exception handler. + * @sev_es_hcall_finish: Copies state from the GHCB back into the + * processor (or pt_regs). Also runs checks on the + * state returned from the hypervisor after a + * VMMCALL under SEV-ES. Needs to return 'false' + * if the checks fail. Called from the #VC + * exception handler. */ struct x86_hyper_runtime { void (*pin_vcpu)(int cpu); + void (*sev_es_hcall_prepare)(struct ghcb *ghcb, struct pt_regs *regs); + bool (*sev_es_hcall_finish)(struct ghcb *ghcb, struct pt_regs *regs); }; /** diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index b0f08d9669f1..76104c71fc85 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -903,6 +903,9 @@ static enum es_result vc_handle_vmmcall(struct ghcb *ghcb, ghcb_set_rax(ghcb, ctxt->regs->ax); ghcb_set_cpl(ghcb, user_mode(ctxt->regs) ? 3 : 0); + if (x86_platform.hyper.sev_es_hcall_prepare) + x86_platform.hyper.sev_es_hcall_prepare(ghcb, ctxt->regs); + ret = sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_VMMCALL, 0, 0); if (ret != ES_OK) return ret; @@ -912,6 +915,15 @@ static enum es_result vc_handle_vmmcall(struct ghcb *ghcb, ctxt->regs->ax = ghcb->save.rax; + /* + * Call sev_es_hcall_finish() after regs->ax is already set. + * This allows the hypervisor handler to overwrite it again if + * necessary. + */ + if (x86_platform.hyper.sev_es_hcall_finish && + !x86_platform.hyper.sev_es_hcall_finish(ghcb, ctxt->regs)) + return ES_VMM_ERROR; + return ES_OK; } From patchwork Tue Jul 14 12:09:07 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662569 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4FBF3618 for ; Tue, 14 Jul 2020 12:12:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3FCBD223C6 for ; Tue, 14 Jul 2020 12:12:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728788AbgGNMMh (ORCPT ); Tue, 14 Jul 2020 08:12:37 -0400 Received: from 8bytes.org ([81.169.241.247]:52886 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728550AbgGNMLS (ORCPT ); Tue, 14 Jul 2020 08:11:18 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id E2823FE4; Tue, 14 Jul 2020 14:11:08 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , Tom Lendacky , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 65/75] x86/kvm: Add KVM specific VMMCALL handling under SEV-ES Date: Tue, 14 Jul 2020 14:09:07 +0200 Message-Id: <20200714120917.11253-66-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Tom Lendacky Implement the callbacks to copy the processor state required by KVM to the GHCB. Signed-off-by: Tom Lendacky [ jroedel@suse.de: - Split out of a larger patch - Adapt to different callback functions ] Co-developed-by: Joerg Roedel Signed-off-by: Joerg Roedel --- arch/x86/kernel/kvm.c | 35 +++++++++++++++++++++++++++++------ 1 file changed, 29 insertions(+), 6 deletions(-) diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index df63786e7bfa..553d6b4eeaa2 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -33,6 +33,8 @@ #include #include #include +#include +#include DEFINE_STATIC_KEY_FALSE(kvm_async_pf_enabled); @@ -729,13 +731,34 @@ static void __init kvm_init_platform(void) x86_platform.apic_post_init = kvm_apic_init; } +#if defined(CONFIG_AMD_MEM_ENCRYPT) +static void kvm_sev_es_hcall_prepare(struct ghcb *ghcb, struct pt_regs *regs) +{ + /* RAX and CPL are already in the GHCB */ + ghcb_set_rbx(ghcb, regs->bx); + ghcb_set_rcx(ghcb, regs->cx); + ghcb_set_rdx(ghcb, regs->dx); + ghcb_set_rsi(ghcb, regs->si); +} + +static bool kvm_sev_es_hcall_finish(struct ghcb *ghcb, struct pt_regs *regs) +{ + /* No checking of the return state needed */ + return true; +} +#endif + const __initconst struct hypervisor_x86 x86_hyper_kvm = { - .name = "KVM", - .detect = kvm_detect, - .type = X86_HYPER_KVM, - .init.guest_late_init = kvm_guest_init, - .init.x2apic_available = kvm_para_available, - .init.init_platform = kvm_init_platform, + .name = "KVM", + .detect = kvm_detect, + .type = X86_HYPER_KVM, + .init.guest_late_init = kvm_guest_init, + .init.x2apic_available = kvm_para_available, + .init.init_platform = kvm_init_platform, +#if defined(CONFIG_AMD_MEM_ENCRYPT) + .runtime.sev_es_hcall_prepare = kvm_sev_es_hcall_prepare, + .runtime.sev_es_hcall_finish = kvm_sev_es_hcall_finish, +#endif }; static __init int activate_jump_labels(void) From patchwork Tue Jul 14 12:09:08 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662563 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E1A4813B4 for ; Tue, 14 Jul 2020 12:12:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D2608222D9 for ; Tue, 14 Jul 2020 12:12:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728571AbgGNMMO (ORCPT ); Tue, 14 Jul 2020 08:12:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60744 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728581AbgGNMLT (ORCPT ); Tue, 14 Jul 2020 08:11:19 -0400 Received: from theia.8bytes.org (8bytes.org [IPv6:2a01:238:4383:600:38bc:a715:4b6d:a889]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1AEC8C061755; Tue, 14 Jul 2020 05:11:19 -0700 (PDT) Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 8C00DFDF; Tue, 14 Jul 2020 14:11:09 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , Doug Covelli , Tom Lendacky , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 66/75] x86/vmware: Add VMware specific handling for VMMCALL under SEV-ES Date: Tue, 14 Jul 2020 14:09:08 +0200 Message-Id: <20200714120917.11253-67-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Doug Covelli Add VMware specific handling for #VC faults caused by VMMCALL instructions. Signed-off-by: Doug Covelli Signed-off-by: Tom Lendacky [ jroedel@suse.de: - Adapt to different paravirt interface ] Co-developed-by: Joerg Roedel Signed-off-by: Joerg Roedel --- arch/x86/kernel/cpu/vmware.c | 50 ++++++++++++++++++++++++++++++++---- 1 file changed, 45 insertions(+), 5 deletions(-) diff --git a/arch/x86/kernel/cpu/vmware.c b/arch/x86/kernel/cpu/vmware.c index 9b6fafa69be9..d2129d5e8373 100644 --- a/arch/x86/kernel/cpu/vmware.c +++ b/arch/x86/kernel/cpu/vmware.c @@ -33,6 +33,7 @@ #include #include #include +#include #undef pr_fmt #define pr_fmt(fmt) "vmware: " fmt @@ -476,10 +477,49 @@ static bool __init vmware_legacy_x2apic_available(void) (eax & (1 << VMWARE_CMD_LEGACY_X2APIC)) != 0; } +#ifdef CONFIG_AMD_MEM_ENCRYPT +static void vmware_sev_es_hcall_prepare(struct ghcb *ghcb, + struct pt_regs *regs) +{ + /* Copy VMWARE specific Hypercall parameters to the GHCB */ + ghcb_set_rip(ghcb, regs->ip); + ghcb_set_rbx(ghcb, regs->bx); + ghcb_set_rcx(ghcb, regs->cx); + ghcb_set_rdx(ghcb, regs->dx); + ghcb_set_rsi(ghcb, regs->si); + ghcb_set_rdi(ghcb, regs->di); + ghcb_set_rbp(ghcb, regs->bp); +} + +static bool vmware_sev_es_hcall_finish(struct ghcb *ghcb, struct pt_regs *regs) +{ + if (!(ghcb_is_valid_rbx(ghcb) && + ghcb_is_valid_rcx(ghcb) && + ghcb_is_valid_rdx(ghcb) && + ghcb_is_valid_rsi(ghcb) && + ghcb_is_valid_rdi(ghcb) && + ghcb_is_valid_rbp(ghcb))) + return false; + + regs->bx = ghcb->save.rbx; + regs->cx = ghcb->save.rcx; + regs->dx = ghcb->save.rdx; + regs->si = ghcb->save.rsi; + regs->di = ghcb->save.rdi; + regs->bp = ghcb->save.rbp; + + return true; +} +#endif + const __initconst struct hypervisor_x86 x86_hyper_vmware = { - .name = "VMware", - .detect = vmware_platform, - .type = X86_HYPER_VMWARE, - .init.init_platform = vmware_platform_setup, - .init.x2apic_available = vmware_legacy_x2apic_available, + .name = "VMware", + .detect = vmware_platform, + .type = X86_HYPER_VMWARE, + .init.init_platform = vmware_platform_setup, + .init.x2apic_available = vmware_legacy_x2apic_available, +#ifdef CONFIG_AMD_MEM_ENCRYPT + .runtime.sev_es_hcall_prepare = vmware_sev_es_hcall_prepare, + .runtime.sev_es_hcall_finish = vmware_sev_es_hcall_finish, +#endif }; From patchwork Tue Jul 14 12:09:09 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662545 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B0CE8618 for ; Tue, 14 Jul 2020 12:11:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A37312242B for ; Tue, 14 Jul 2020 12:11:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728606AbgGNMLV (ORCPT ); Tue, 14 Jul 2020 08:11:21 -0400 Received: from 8bytes.org ([81.169.241.247]:54694 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728572AbgGNMLT (ORCPT ); Tue, 14 Jul 2020 08:11:19 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 1D21FFE7; Tue, 14 Jul 2020 14:11:10 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 67/75] x86/realmode: Add SEV-ES specific trampoline entry point Date: Tue, 14 Jul 2020 14:09:09 +0200 Message-Id: <20200714120917.11253-68-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel The code at the trampoline entry point is executed in real-mode. In real-mode #VC exceptions can't be handled, so anything that might cause such an exception must be avoided. In the standard trampoline entry code this is the WBINVD instruction and the call to verify_cpu(), which are both not needed anyway when running as an SEV-ES guest. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/realmode.h | 3 +++ arch/x86/realmode/rm/header.S | 3 +++ arch/x86/realmode/rm/trampoline_64.S | 20 ++++++++++++++++++++ 3 files changed, 26 insertions(+) diff --git a/arch/x86/include/asm/realmode.h b/arch/x86/include/asm/realmode.h index b35030eeec36..6590394af309 100644 --- a/arch/x86/include/asm/realmode.h +++ b/arch/x86/include/asm/realmode.h @@ -21,6 +21,9 @@ struct real_mode_header { /* SMP trampoline */ u32 trampoline_start; u32 trampoline_header; +#ifdef CONFIG_AMD_MEM_ENCRYPT + u32 sev_es_trampoline_start; +#endif #ifdef CONFIG_X86_64 u32 trampoline_pgd; #endif diff --git a/arch/x86/realmode/rm/header.S b/arch/x86/realmode/rm/header.S index af04512c02d9..8c1db5bf5d78 100644 --- a/arch/x86/realmode/rm/header.S +++ b/arch/x86/realmode/rm/header.S @@ -20,6 +20,9 @@ SYM_DATA_START(real_mode_header) /* SMP trampoline */ .long pa_trampoline_start .long pa_trampoline_header +#ifdef CONFIG_AMD_MEM_ENCRYPT + .long pa_sev_es_trampoline_start +#endif #ifdef CONFIG_X86_64 .long pa_trampoline_pgd; #endif diff --git a/arch/x86/realmode/rm/trampoline_64.S b/arch/x86/realmode/rm/trampoline_64.S index 251758ed7443..84c5d1b33d10 100644 --- a/arch/x86/realmode/rm/trampoline_64.S +++ b/arch/x86/realmode/rm/trampoline_64.S @@ -56,6 +56,7 @@ SYM_CODE_START(trampoline_start) testl %eax, %eax # Check for return code jnz no_longmode +.Lswitch_to_protected: /* * GDT tables in non default location kernel can be beyond 16MB and * lgdt will not be able to load the address as in real mode default @@ -80,6 +81,25 @@ no_longmode: jmp no_longmode SYM_CODE_END(trampoline_start) +#ifdef CONFIG_AMD_MEM_ENCRYPT +/* SEV-ES supports non-zero IP for entry points - no alignment needed */ +SYM_CODE_START(sev_es_trampoline_start) + cli # We should be safe anyway + + LJMPW_RM(1f) +1: + mov %cs, %ax # Code and data in the same place + mov %ax, %ds + mov %ax, %es + mov %ax, %ss + + # Setup stack + movl $rm_stack_end, %esp + + jmp .Lswitch_to_protected +SYM_CODE_END(sev_es_trampoline_start) +#endif /* CONFIG_AMD_MEM_ENCRYPT */ + #include "../kernel/verify_cpu.S" .section ".text32","ax" From patchwork Tue Jul 14 12:09:10 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662561 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 17739618 for ; Tue, 14 Jul 2020 12:12:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 04D2F2236F for ; Tue, 14 Jul 2020 12:12:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728752AbgGNMMP (ORCPT ); Tue, 14 Jul 2020 08:12:15 -0400 Received: from 8bytes.org ([81.169.241.247]:52886 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728576AbgGNMLT (ORCPT ); Tue, 14 Jul 2020 08:11:19 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id A05E9FE9; Tue, 14 Jul 2020 14:11:10 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , Tom Lendacky , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 68/75] x86/realmode: Setup AP jump table Date: Tue, 14 Jul 2020 14:09:10 +0200 Message-Id: <20200714120917.11253-69-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Tom Lendacky As part of the GHCB specification, the booting of APs under SEV-ES requires an AP jump table when transitioning from one layer of code to another (e.g. when going from UEFI to the OS). As a result, each layer that parks an AP must provide the physical address of an AP jump table to the next layer via the hypervisor. Upon booting of the kernel, read the AP jump table address from the hypervisor. Under SEV-ES, APs are started using the INIT-SIPI-SIPI sequence. Before issuing the first SIPI request for an AP, the start CS and IP is programmed into the AP jump table. Upon issuing the SIPI request, the AP will awaken and jump to that start CS:IP address. Signed-off-by: Tom Lendacky [ jroedel@suse.de: - Adapted to different code base - Moved AP table setup from SIPI sending path to real-mode setup code - Fix sparse warnings ] Co-developed-by: Joerg Roedel Signed-off-by: Joerg Roedel --- arch/x86/include/asm/sev-es.h | 5 +++ arch/x86/include/uapi/asm/svm.h | 3 ++ arch/x86/kernel/sev-es.c | 68 +++++++++++++++++++++++++++++++++ arch/x86/realmode/init.c | 18 ++++++++- 4 files changed, 92 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/sev-es.h b/arch/x86/include/asm/sev-es.h index 330140a189be..25ab44f977db 100644 --- a/arch/x86/include/asm/sev-es.h +++ b/arch/x86/include/asm/sev-es.h @@ -73,6 +73,9 @@ static inline u64 lower_bits(u64 val, unsigned int bits) return (val & mask); } +struct real_mode_header; +enum stack_type; + /* Early IDT entry points for #VC handler */ extern void vc_no_ghcb(void); extern bool handle_vc_boot_ghcb(struct pt_regs *regs); @@ -80,9 +83,11 @@ extern bool handle_vc_boot_ghcb(struct pt_regs *regs); #ifdef CONFIG_AMD_MEM_ENCRYPT extern void sev_es_ist_enter(struct pt_regs *regs); extern void sev_es_ist_exit(void); +extern int sev_es_setup_ap_jump_table(struct real_mode_header *rmh); #else static inline void sev_es_ist_enter(struct pt_regs *regs) { } static inline void sev_es_ist_exit(void) { } +static inline int sev_es_setup_ap_jump_table(struct real_mode_header *rmh) { return 0; } #endif #endif diff --git a/arch/x86/include/uapi/asm/svm.h b/arch/x86/include/uapi/asm/svm.h index 8f36ae021a7f..a19ce9681ec2 100644 --- a/arch/x86/include/uapi/asm/svm.h +++ b/arch/x86/include/uapi/asm/svm.h @@ -84,6 +84,9 @@ /* SEV-ES software-defined VMGEXIT events */ #define SVM_VMGEXIT_MMIO_READ 0x80000001 #define SVM_VMGEXIT_MMIO_WRITE 0x80000002 +#define SVM_VMGEXIT_AP_JUMP_TABLE 0x80000005 +#define SVM_VMGEXIT_SET_AP_JUMP_TABLE 0 +#define SVM_VMGEXIT_GET_AP_JUMP_TABLE 1 #define SVM_VMGEXIT_UNSUPPORTED_EVENT 0x8000ffff #define SVM_EXIT_ERR -1 diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index 76104c71fc85..370cf9bf2c88 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -21,6 +21,8 @@ #include #include +#include +#include #include #include #include @@ -229,6 +231,9 @@ static __always_inline void sev_es_put_ghcb(struct ghcb_state *state) } } +/* Needed in vc_early_vc_forward_exception */ +void do_early_exception(struct pt_regs *regs, int trapnr); + static inline u64 sev_es_rd_ghcb_msr(void) { return native_read_msr(MSR_AMD64_SEV_ES_GHCB); @@ -416,6 +421,69 @@ static bool vc_slow_virt_to_phys(struct ghcb *ghcb, struct es_em_ctxt *ctxt, /* Include code shared with pre-decompression boot stage */ #include "sev-es-shared.c" +static u64 sev_es_get_jump_table_addr(void) +{ + struct ghcb_state state; + unsigned long flags; + struct ghcb *ghcb; + u64 ret; + + local_irq_save(flags); + + ghcb = sev_es_get_ghcb(&state); + + vc_ghcb_invalidate(ghcb); + ghcb_set_sw_exit_code(ghcb, SVM_VMGEXIT_AP_JUMP_TABLE); + ghcb_set_sw_exit_info_1(ghcb, SVM_VMGEXIT_GET_AP_JUMP_TABLE); + ghcb_set_sw_exit_info_2(ghcb, 0); + + sev_es_wr_ghcb_msr(__pa(ghcb)); + VMGEXIT(); + + if (!ghcb_is_valid_sw_exit_info_1(ghcb) || + !ghcb_is_valid_sw_exit_info_2(ghcb)) + ret = 0; + + ret = ghcb->save.sw_exit_info_2; + + sev_es_put_ghcb(&state); + + local_irq_restore(flags); + + return ret; +} + +int sev_es_setup_ap_jump_table(struct real_mode_header *rmh) +{ + u16 startup_cs, startup_ip; + phys_addr_t jump_table_pa; + u64 jump_table_addr; + u16 __iomem *jump_table; + + jump_table_addr = sev_es_get_jump_table_addr(); + + /* Check if AP Jump Table is non-zero and page-aligned */ + if (!jump_table_addr || jump_table_addr & ~PAGE_MASK) + return 0; + + jump_table_pa = jump_table_addr & PAGE_MASK; + + startup_cs = (u16)(rmh->trampoline_start >> 4); + startup_ip = (u16)(rmh->sev_es_trampoline_start - + rmh->trampoline_start); + + jump_table = ioremap_encrypted(jump_table_pa, PAGE_SIZE); + if (!jump_table) + return -EIO; + + writew(startup_ip, &jump_table[0]); + writew(startup_cs, &jump_table[1]); + + iounmap(jump_table); + + return 0; +} + static enum es_result vc_handle_msr(struct ghcb *ghcb, struct es_em_ctxt *ctxt) { struct pt_regs *regs = ctxt->regs; diff --git a/arch/x86/realmode/init.c b/arch/x86/realmode/init.c index 1ed1208931e0..61a52b925d15 100644 --- a/arch/x86/realmode/init.c +++ b/arch/x86/realmode/init.c @@ -9,6 +9,7 @@ #include #include #include +#include struct real_mode_header *real_mode_header; u32 *trampoline_cr4_features; @@ -38,6 +39,19 @@ void __init reserve_real_mode(void) crash_reserve_low_1M(); } +static void sme_sev_setup_real_mode(struct trampoline_header *th) +{ +#ifdef CONFIG_AMD_MEM_ENCRYPT + if (sme_active()) + th->flags |= TH_FLAGS_SME_ACTIVE; + + if (sev_es_active()) { + if (sev_es_setup_ap_jump_table(real_mode_header)) + panic("Failed to update SEV-ES AP Jump Table"); + } +#endif +} + static void __init setup_real_mode(void) { u16 real_mode_seg; @@ -104,13 +118,13 @@ static void __init setup_real_mode(void) *trampoline_cr4_features = mmu_cr4_features; trampoline_header->flags = 0; - if (sme_active()) - trampoline_header->flags |= TH_FLAGS_SME_ACTIVE; trampoline_pgd = (u64 *) __va(real_mode_header->trampoline_pgd); trampoline_pgd[0] = trampoline_pgd_entry.pgd; trampoline_pgd[511] = init_top_pgt[511].pgd; #endif + + sme_sev_setup_real_mode(trampoline_header); } /* From patchwork Tue Jul 14 12:09:11 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662557 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 329E2618 for ; Tue, 14 Jul 2020 12:12:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 232E1223C6 for ; Tue, 14 Jul 2020 12:12:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728717AbgGNMMA (ORCPT ); Tue, 14 Jul 2020 08:12:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60748 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728595AbgGNMLU (ORCPT ); Tue, 14 Jul 2020 08:11:20 -0400 Received: from theia.8bytes.org (8bytes.org [IPv6:2a01:238:4383:600:38bc:a715:4b6d:a889]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9EA51C061794; Tue, 14 Jul 2020 05:11:20 -0700 (PDT) Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 3BFD8FEA; Tue, 14 Jul 2020 14:11:11 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 69/75] x86/head/64: Setup TSS early for secondary CPUs Date: Tue, 14 Jul 2020 14:09:11 +0200 Message-Id: <20200714120917.11253-70-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel The #VC exception will trigger very early in head_64.S, when the first CPUID instruction is executed. When secondary CPUs boot, they already load the real system IDT, which has the #VC handler configured to use an IST stack. IST stacks require a TSS to be loaded, so set up the TSS early for bringing up the secondary CPUs. Use the read-write version of the per-CPU TSS struct early, until cpu_init() switches to the read-only mapping. On the boot CPU the TSS will also be loaded early, but not used as the the early boot #VC handlers do not use IST stacks. Signed-off-by: Joerg Roedel --- arch/x86/kernel/head64.c | 13 +++++++++++++ arch/x86/kernel/head_64.S | 5 +++++ 2 files changed, 18 insertions(+) diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index 23d492091f3b..f57eefb1e4ba 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -545,6 +545,19 @@ void __head early_idt_setup_early_handler(unsigned long descr_addr, unsigned lon } } +void __head early_load_tss(void) +{ + struct desc_struct *gdt = (struct desc_struct *)boot_gdt; + struct tss_struct *tss = this_cpu_ptr(&cpu_tss_rw); + tss_desc tss_desc; + + set_tssldt_descriptor(&tss_desc, (unsigned long)tss, DESC_TSS, + __KERNEL_TSS_LIMIT); + native_write_gdt_entry(gdt, GDT_ENTRY_TSS, &tss_desc, DESC_TSS); + + asm volatile("ltr %w0"::"q" (GDT_ENTRY_TSS*8)); +} + #ifdef CONFIG_AMD_MEM_ENCRYPT static void __head set_early_idt_handler(gate_desc *idt, int n, void *handler) { diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 3bd4c36d1d36..5b577d6bce7a 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -235,6 +235,11 @@ SYM_CODE_START(secondary_startup_64) */ movq initial_stack(%rip), %rsp + /* Setup a TSS for early IST handlers - needs %gs to be set up */ + pushq %rsi + call early_load_tss + popq %rsi + /* Load IDT */ lidt idt_descr(%rip) From patchwork Tue Jul 14 12:09:12 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662559 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 17EE7618 for ; Tue, 14 Jul 2020 12:12:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 089562236F for ; Tue, 14 Jul 2020 12:12:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728708AbgGNML7 (ORCPT ); Tue, 14 Jul 2020 08:11:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60750 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728603AbgGNMLV (ORCPT ); Tue, 14 Jul 2020 08:11:21 -0400 Received: from theia.8bytes.org (8bytes.org [IPv6:2a01:238:4383:600:38bc:a715:4b6d:a889]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2AB2DC08C5DB; Tue, 14 Jul 2020 05:11:21 -0700 (PDT) Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id B9D2CFED; Tue, 14 Jul 2020 14:11:11 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 70/75] x86/head/64: Don't call verify_cpu() on starting APs Date: Tue, 14 Jul 2020 14:09:12 +0200 Message-Id: <20200714120917.11253-71-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel The APs are not ready to handle exceptions when verify_cpu() is called in secondary_startup_64. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/realmode.h | 1 + arch/x86/kernel/head_64.S | 1 + arch/x86/realmode/init.c | 6 ++++++ 3 files changed, 8 insertions(+) diff --git a/arch/x86/include/asm/realmode.h b/arch/x86/include/asm/realmode.h index 6590394af309..5c97807c38a4 100644 --- a/arch/x86/include/asm/realmode.h +++ b/arch/x86/include/asm/realmode.h @@ -69,6 +69,7 @@ extern unsigned char startup_32_smp[]; extern unsigned char boot_gdt[]; #else extern unsigned char secondary_startup_64[]; +extern unsigned char secondary_startup_64_no_verify[]; #endif static inline size_t real_mode_size_needed(void) diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 5b577d6bce7a..8b43ed0592e8 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -165,6 +165,7 @@ SYM_CODE_START(secondary_startup_64) /* Sanitize CPU configuration */ call verify_cpu +SYM_INNER_LABEL(secondary_startup_64_no_verify, SYM_L_GLOBAL) /* * Retrieve the modifier (SME encryption mask if SME is active) to be * added to the initial pgdir entry that will be programmed into CR3. diff --git a/arch/x86/realmode/init.c b/arch/x86/realmode/init.c index 61a52b925d15..df701f87ddef 100644 --- a/arch/x86/realmode/init.c +++ b/arch/x86/realmode/init.c @@ -46,6 +46,12 @@ static void sme_sev_setup_real_mode(struct trampoline_header *th) th->flags |= TH_FLAGS_SME_ACTIVE; if (sev_es_active()) { + /* + * Skip the call to verify_cpu() in secondary_startup_64 as it + * will cause #VC exceptions when the AP can't handle them yet. + */ + th->start = (u64) secondary_startup_64_no_verify; + if (sev_es_setup_ap_jump_table(real_mode_header)) panic("Failed to update SEV-ES AP Jump Table"); } From patchwork Tue Jul 14 12:09:13 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662555 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 0019F618 for ; Tue, 14 Jul 2020 12:12:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DF2E9222B6 for ; Tue, 14 Jul 2020 12:11:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728691AbgGNML7 (ORCPT ); Tue, 14 Jul 2020 08:11:59 -0400 Received: from 8bytes.org ([81.169.241.247]:54694 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728594AbgGNMLV (ORCPT ); Tue, 14 Jul 2020 08:11:21 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 41641FEE; Tue, 14 Jul 2020 14:11:12 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 71/75] x86/head/64: Rename start_cpu0 Date: Tue, 14 Jul 2020 14:09:13 +0200 Message-Id: <20200714120917.11253-72-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel For SEV-ES this entry point will be used for restarting APs after they have been offlined. Remove the '0' from the name to reflect that. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/cpu.h | 2 +- arch/x86/kernel/head_32.S | 4 ++-- arch/x86/kernel/head_64.S | 6 +++--- arch/x86/kernel/smpboot.c | 4 ++-- 4 files changed, 8 insertions(+), 8 deletions(-) diff --git a/arch/x86/include/asm/cpu.h b/arch/x86/include/asm/cpu.h index da78ccbd493b..1536b607971f 100644 --- a/arch/x86/include/asm/cpu.h +++ b/arch/x86/include/asm/cpu.h @@ -29,7 +29,7 @@ struct x86_cpu { #ifdef CONFIG_HOTPLUG_CPU extern int arch_register_cpu(int num); extern void arch_unregister_cpu(int); -extern void start_cpu0(void); +extern void start_cpu(void); #ifdef CONFIG_DEBUG_HOTPLUG_CPU0 extern int _debug_hotplug_cpu(int cpu, int action); #endif diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S index f66a6b90f954..aad62c677486 100644 --- a/arch/x86/kernel/head_32.S +++ b/arch/x86/kernel/head_32.S @@ -174,12 +174,12 @@ SYM_CODE_END(startup_32) * up already except stack. We just set up stack here. Then call * start_secondary(). */ -SYM_FUNC_START(start_cpu0) +SYM_FUNC_START(start_cpu) movl initial_stack, %ecx movl %ecx, %esp call *(initial_code) 1: jmp 1b -SYM_FUNC_END(start_cpu0) +SYM_FUNC_END(start_cpu) #endif /* diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 8b43ed0592e8..12d1e407461c 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -319,15 +319,15 @@ SYM_CODE_END(secondary_startup_64) #ifdef CONFIG_HOTPLUG_CPU /* - * Boot CPU0 entry point. It's called from play_dead(). Everything has been set + * CPU entry point. It's called from play_dead(). Everything has been set * up already except stack. We just set up stack here. Then call * start_secondary() via .Ljump_to_C_code. */ -SYM_CODE_START(start_cpu0) +SYM_CODE_START(start_cpu) UNWIND_HINT_EMPTY movq initial_stack(%rip), %rsp jmp .Ljump_to_C_code -SYM_CODE_END(start_cpu0) +SYM_CODE_END(start_cpu) #endif /* Both SMP bootup and ACPI suspend change these variables */ diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index ffbd9a3d78d8..5a173459759d 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -1729,7 +1729,7 @@ static inline void mwait_play_dead(void) * If NMI wants to wake up CPU0, start CPU0. */ if (wakeup_cpu0()) - start_cpu0(); + start_cpu(); } } @@ -1744,7 +1744,7 @@ void hlt_play_dead(void) * If NMI wants to wake up CPU0, start CPU0. */ if (wakeup_cpu0()) - start_cpu0(); + start_cpu(); } } From patchwork Tue Jul 14 12:09:14 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662549 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 9A817618 for ; Tue, 14 Jul 2020 12:11:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8C04C22464 for ; Tue, 14 Jul 2020 12:11:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728683AbgGNMLn (ORCPT ); Tue, 14 Jul 2020 08:11:43 -0400 Received: from 8bytes.org ([81.169.241.247]:54824 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728502AbgGNMLW (ORCPT ); Tue, 14 Jul 2020 08:11:22 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id C4FB6FF1; Tue, 14 Jul 2020 14:11:12 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 72/75] x86/sev-es: Support CPU offline/online Date: Tue, 14 Jul 2020 14:09:14 +0200 Message-Id: <20200714120917.11253-73-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Add a play_dead handler when running under SEV-ES. This is needed because the hypervisor can't deliver an SIPI request to restart the AP. Instead the kernel has to issue a VMGEXIT to halt the VCPU until the hypervisor wakes it up again. Signed-off-by: Joerg Roedel --- arch/x86/include/uapi/asm/svm.h | 1 + arch/x86/kernel/sev-es.c | 64 +++++++++++++++++++++++++++++++++ 2 files changed, 65 insertions(+) diff --git a/arch/x86/include/uapi/asm/svm.h b/arch/x86/include/uapi/asm/svm.h index a19ce9681ec2..20a05839dd9a 100644 --- a/arch/x86/include/uapi/asm/svm.h +++ b/arch/x86/include/uapi/asm/svm.h @@ -84,6 +84,7 @@ /* SEV-ES software-defined VMGEXIT events */ #define SVM_VMGEXIT_MMIO_READ 0x80000001 #define SVM_VMGEXIT_MMIO_WRITE 0x80000002 +#define SVM_VMGEXIT_AP_HLT_LOOP 0x80000004 #define SVM_VMGEXIT_AP_JUMP_TABLE 0x80000005 #define SVM_VMGEXIT_SET_AP_JUMP_TABLE 0 #define SVM_VMGEXIT_GET_AP_JUMP_TABLE 1 diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index 370cf9bf2c88..b147d97856c3 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -29,6 +29,8 @@ #include #include #include +#include +#include #define DR7_RESET_VALUE 0x400 @@ -531,6 +533,66 @@ static bool __init sev_es_setup_ghcb(void) return true; } +#ifdef CONFIG_HOTPLUG_CPU +static void sev_es_ap_hlt_loop(void) +{ + struct ghcb_state state; + struct ghcb *ghcb; + + ghcb = sev_es_get_ghcb(&state); + + while (true) { + vc_ghcb_invalidate(ghcb); + ghcb_set_sw_exit_code(ghcb, SVM_VMGEXIT_AP_HLT_LOOP); + ghcb_set_sw_exit_info_1(ghcb, 0); + ghcb_set_sw_exit_info_2(ghcb, 0); + + sev_es_wr_ghcb_msr(__pa(ghcb)); + VMGEXIT(); + + /* Wakeup signal? */ + if (ghcb_is_valid_sw_exit_info_2(ghcb) && + ghcb->save.sw_exit_info_2) + break; + } + + sev_es_put_ghcb(&state); +} + +/* + * Play_dead handler when running under SEV-ES. This is needed because + * the hypervisor can't deliver an SIPI request to restart the AP. + * Instead the kernel has to issue a VMGEXIT to halt the VCPU until the + * hypervisor wakes it up again. + */ +static void sev_es_play_dead(void) +{ + play_dead_common(); + + /* IRQs now disabled */ + + sev_es_ap_hlt_loop(); + + /* + * If we get here, the VCPU was woken up again. Jump to CPU + * startup code to get it back online. + */ + + start_cpu(); +} +#else /* CONFIG_HOTPLUG_CPU */ +#define sev_es_play_dead native_play_dead +#endif /* CONFIG_HOTPLUG_CPU */ + +#ifdef CONFIG_SMP +static void __init sev_es_setup_play_dead(void) +{ + smp_ops.play_dead = sev_es_play_dead; +} +#else +static inline void sev_es_setup_play_dead(void) { } +#endif + static void __init sev_es_alloc_runtime_data(int cpu) { struct sev_es_runtime_data *data; @@ -575,6 +637,8 @@ void __init sev_es_init_vc_handling(void) sev_es_init_ghcb(cpu); sev_es_setup_vc_stacks(cpu); } + + sev_es_setup_play_dead(); } static void __init vc_early_forward_exception(struct es_em_ctxt *ctxt) From patchwork Tue Jul 14 12:09:15 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662551 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4121713B4 for ; Tue, 14 Jul 2020 12:11:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2F88F222B6 for ; Tue, 14 Jul 2020 12:11:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728672AbgGNMLm (ORCPT ); Tue, 14 Jul 2020 08:11:42 -0400 Received: from 8bytes.org ([81.169.241.247]:54846 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728605AbgGNMLX (ORCPT ); Tue, 14 Jul 2020 08:11:23 -0400 Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 7452BFF0; Tue, 14 Jul 2020 14:11:13 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 73/75] x86/sev-es: Handle NMI State Date: Tue, 14 Jul 2020 14:09:15 +0200 Message-Id: <20200714120917.11253-74-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel When running under SEV-ES the kernel has to tell the hypervisor when to open the NMI window again after an NMI was injected. This is done with an NMI-complete message to the hypervisor. Add code to the kernels NMI handler to send this message right at the beginning of do_nmi(). This always allows nesting NMIs. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/sev-es.h | 2 ++ arch/x86/include/uapi/asm/svm.h | 1 + arch/x86/kernel/nmi.c | 6 ++++++ arch/x86/kernel/sev-es.c | 21 +++++++++++++++++++++ 4 files changed, 30 insertions(+) diff --git a/arch/x86/include/asm/sev-es.h b/arch/x86/include/asm/sev-es.h index 25ab44f977db..de4d3f63fdf8 100644 --- a/arch/x86/include/asm/sev-es.h +++ b/arch/x86/include/asm/sev-es.h @@ -84,10 +84,12 @@ extern bool handle_vc_boot_ghcb(struct pt_regs *regs); extern void sev_es_ist_enter(struct pt_regs *regs); extern void sev_es_ist_exit(void); extern int sev_es_setup_ap_jump_table(struct real_mode_header *rmh); +extern void sev_es_nmi_complete(void); #else static inline void sev_es_ist_enter(struct pt_regs *regs) { } static inline void sev_es_ist_exit(void) { } static inline int sev_es_setup_ap_jump_table(struct real_mode_header *rmh) { return 0; } +static inline void sev_es_nmi_complete(void) { } #endif #endif diff --git a/arch/x86/include/uapi/asm/svm.h b/arch/x86/include/uapi/asm/svm.h index 20a05839dd9a..0f837339db66 100644 --- a/arch/x86/include/uapi/asm/svm.h +++ b/arch/x86/include/uapi/asm/svm.h @@ -84,6 +84,7 @@ /* SEV-ES software-defined VMGEXIT events */ #define SVM_VMGEXIT_MMIO_READ 0x80000001 #define SVM_VMGEXIT_MMIO_WRITE 0x80000002 +#define SVM_VMGEXIT_NMI_COMPLETE 0x80000003 #define SVM_VMGEXIT_AP_HLT_LOOP 0x80000004 #define SVM_VMGEXIT_AP_JUMP_TABLE 0x80000005 #define SVM_VMGEXIT_SET_AP_JUMP_TABLE 0 diff --git a/arch/x86/kernel/nmi.c b/arch/x86/kernel/nmi.c index d94a5bb0bebc..2d60220bf6d5 100644 --- a/arch/x86/kernel/nmi.c +++ b/arch/x86/kernel/nmi.c @@ -479,6 +479,12 @@ static DEFINE_PER_CPU(unsigned long, nmi_dr7); DEFINE_IDTENTRY_RAW(exc_nmi) { + /* + * Re-enable NMIs right here when running as an SEV-ES guest. This might + * cause nested NMIs, but those can be handled safely. + */ + sev_es_nmi_complete(); + if (IS_ENABLED(CONFIG_SMP) && arch_cpu_is_offline(smp_processor_id())) return; diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index b147d97856c3..ff440b6e5e78 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -423,6 +423,27 @@ static bool vc_slow_virt_to_phys(struct ghcb *ghcb, struct es_em_ctxt *ctxt, /* Include code shared with pre-decompression boot stage */ #include "sev-es-shared.c" +void sev_es_nmi_complete(void) +{ + struct ghcb_state state; + struct ghcb *ghcb; + + if (!sev_es_active()) + return; + + ghcb = sev_es_get_ghcb(&state); + + vc_ghcb_invalidate(ghcb); + ghcb_set_sw_exit_code(ghcb, SVM_VMGEXIT_NMI_COMPLETE); + ghcb_set_sw_exit_info_1(ghcb, 0); + ghcb_set_sw_exit_info_2(ghcb, 0); + + sev_es_wr_ghcb_msr(__pa(ghcb)); + VMGEXIT(); + + sev_es_put_ghcb(&state); +} + static u64 sev_es_get_jump_table_addr(void) { struct ghcb_state state; From patchwork Tue Jul 14 12:09:16 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662553 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 12906618 for ; Tue, 14 Jul 2020 12:11:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 044272236F for ; Tue, 14 Jul 2020 12:11:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728662AbgGNMLm (ORCPT ); Tue, 14 Jul 2020 08:11:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60758 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728612AbgGNMLX (ORCPT ); Tue, 14 Jul 2020 08:11:23 -0400 Received: from theia.8bytes.org (8bytes.org [IPv6:2a01:238:4383:600:38bc:a715:4b6d:a889]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B88C3C08C5DD; Tue, 14 Jul 2020 05:11:22 -0700 (PDT) Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 26D7FFF3; Tue, 14 Jul 2020 14:11:14 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , Tom Lendacky , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 74/75] x86/efi: Add GHCB mappings when SEV-ES is active Date: Tue, 14 Jul 2020 14:09:16 +0200 Message-Id: <20200714120917.11253-75-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Tom Lendacky Calling down to EFI runtime services can result in the firmware performing VMGEXIT calls. The firmware is likely to use the GHCB of the OS (e.g., for setting EFI variables), so each GHCB in the system needs to be identity mapped in the EFI page tables, as unencrypted, to avoid page faults. Signed-off-by: Tom Lendacky [ jroedel@suse.de: Moved GHCB mapping loop to sev-es.c ] Signed-off-by: Joerg Roedel --- arch/x86/boot/compressed/sev-es.c | 1 + arch/x86/include/asm/sev-es.h | 2 ++ arch/x86/kernel/sev-es.c | 30 ++++++++++++++++++++++++++++++ arch/x86/platform/efi/efi_64.c | 10 ++++++++++ 4 files changed, 43 insertions(+) diff --git a/arch/x86/boot/compressed/sev-es.c b/arch/x86/boot/compressed/sev-es.c index 1ce144e0ddc3..b522c18c0588 100644 --- a/arch/x86/boot/compressed/sev-es.c +++ b/arch/x86/boot/compressed/sev-es.c @@ -12,6 +12,7 @@ */ #include "misc.h" +#include #include #include #include diff --git a/arch/x86/include/asm/sev-es.h b/arch/x86/include/asm/sev-es.h index de4d3f63fdf8..03e114c727c8 100644 --- a/arch/x86/include/asm/sev-es.h +++ b/arch/x86/include/asm/sev-es.h @@ -85,11 +85,13 @@ extern void sev_es_ist_enter(struct pt_regs *regs); extern void sev_es_ist_exit(void); extern int sev_es_setup_ap_jump_table(struct real_mode_header *rmh); extern void sev_es_nmi_complete(void); +extern int __init sev_es_efi_map_ghcbs(pgd_t *pgd); #else static inline void sev_es_ist_enter(struct pt_regs *regs) { } static inline void sev_es_ist_exit(void) { } static inline int sev_es_setup_ap_jump_table(struct real_mode_header *rmh) { return 0; } static inline void sev_es_nmi_complete(void) { } +static inline int sev_es_efi_map_ghcbs(pgd_t *pgd) { return 0; } #endif #endif diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index ff440b6e5e78..61308f9c8138 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -507,6 +507,36 @@ int sev_es_setup_ap_jump_table(struct real_mode_header *rmh) return 0; } +/* + * This is needed by the OVMF UEFI firmware which will use whatever it finds in + * the GHCB MSR as its GHCB to talk to the hypervisor. So make sure the per-cpu + * runtime GHCBs used by the kernel are also mapped in the EFI page-table. + */ +int __init sev_es_efi_map_ghcbs(pgd_t *pgd) +{ + struct sev_es_runtime_data *data; + unsigned long address, pflags; + int cpu; + u64 pfn; + + if (!sev_es_active()) + return 0; + + pflags = _PAGE_NX | _PAGE_RW; + + for_each_possible_cpu(cpu) { + data = per_cpu(runtime_data, cpu); + + address = __pa(&data->ghcb_page); + pfn = address >> PAGE_SHIFT; + + if (kernel_map_pages_in_pgd(pgd, pfn, address, 1, pflags)) + return 1; + } + + return 0; +} + static enum es_result vc_handle_msr(struct ghcb *ghcb, struct es_em_ctxt *ctxt) { struct pt_regs *regs = ctxt->regs; diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c index 8e364c4c6768..42e0628c45ca 100644 --- a/arch/x86/platform/efi/efi_64.c +++ b/arch/x86/platform/efi/efi_64.c @@ -47,6 +47,7 @@ #include #include #include +#include /* * We allocate runtime services regions top-down, starting from -4G, i.e. @@ -238,6 +239,15 @@ int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages) return 1; } + /* + * When SEV-ES is active, the GHCB as set by the kernel will be used + * by firmware. Create a 1:1 unencrypted mapping for each GHCB. + */ + if (sev_es_efi_map_ghcbs(pgd)) { + pr_err("Failed to create 1:1 mapping for the GHCBs!\n"); + return 1; + } + /* * When making calls to the firmware everything needs to be 1:1 * mapped and addressable with 32-bit pointers. Map the kernel From patchwork Tue Jul 14 12:09:17 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11662547 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 35F2C13B4 for ; Tue, 14 Jul 2020 12:11:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 27BE02245F for ; Tue, 14 Jul 2020 12:11:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728590AbgGNMLg (ORCPT ); Tue, 14 Jul 2020 08:11:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60770 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728541AbgGNMLZ (ORCPT ); Tue, 14 Jul 2020 08:11:25 -0400 Received: from theia.8bytes.org (8bytes.org [IPv6:2a01:238:4383:600:38bc:a715:4b6d:a889]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 73139C08C5DF; Tue, 14 Jul 2020 05:11:23 -0700 (PDT) Received: from cap.home.8bytes.org (p5b006776.dip0.t-ipconnect.de [91.0.103.118]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id B1749FF5; Tue, 14 Jul 2020 14:11:14 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , Martin Radev , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v4 75/75] x86/sev-es: Check required CPU features for SEV-ES Date: Tue, 14 Jul 2020 14:09:17 +0200 Message-Id: <20200714120917.11253-76-joro@8bytes.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714120917.11253-1-joro@8bytes.org> References: <20200714120917.11253-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Martin Radev Make sure the machine supports RDRAND, otherwise there is no trusted source of of randomness in the system. Signed-off-by: Martin Radev Signed-off-by: Joerg Roedel --- arch/x86/boot/compressed/sev-es.c | 3 +++ arch/x86/kernel/sev-es-shared.c | 15 +++++++++++++++ arch/x86/kernel/sev-es.c | 3 +++ 3 files changed, 21 insertions(+) diff --git a/arch/x86/boot/compressed/sev-es.c b/arch/x86/boot/compressed/sev-es.c index b522c18c0588..eb1a8b5cc753 100644 --- a/arch/x86/boot/compressed/sev-es.c +++ b/arch/x86/boot/compressed/sev-es.c @@ -145,6 +145,9 @@ void sev_es_shutdown_ghcb(void) if (!boot_ghcb) return; + if (!sev_es_check_cpu_features()) + error("SEV-ES CPU Features missing."); + /* * GHCB Page must be flushed from the cache and mapped encrypted again. * Otherwise the running kernel will see strange cache effects when diff --git a/arch/x86/kernel/sev-es-shared.c b/arch/x86/kernel/sev-es-shared.c index 608f76d0d088..56de70cb80d8 100644 --- a/arch/x86/kernel/sev-es-shared.c +++ b/arch/x86/kernel/sev-es-shared.c @@ -9,6 +9,21 @@ * and is included directly into both code-bases. */ +#ifndef __BOOT_COMPRESSED +#define error(v) pr_err(v) +#define has_cpuflag(f) boot_cpu_has(f) +#endif + +static bool __init sev_es_check_cpu_features(void) +{ + if (!has_cpuflag(X86_FEATURE_RDRAND)) { + error("RDRAND instruction not supported - no trusted source of randomness available\n"); + return false; + } + + return true; +} + static void sev_es_terminate(unsigned int reason) { u64 val = GHCB_SEV_TERMINATE; diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index 61308f9c8138..481ea00c58b6 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -682,6 +682,9 @@ void __init sev_es_init_vc_handling(void) if (!sev_es_active()) return; + if (!sev_es_check_cpu_features()) + panic("SEV-ES CPU Features missing"); + /* Initialize per-cpu GHCB pages */ for_each_possible_cpu(cpu) { sev_es_alloc_runtime_data(cpu);