From patchwork Tue Sep 15 10:46:36 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Scull X-Patchwork-Id: 11776159 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 6C7BE6CA for ; Tue, 15 Sep 2020 11:04:21 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 04CC221D24 for ; Tue, 15 Sep 2020 11:04:20 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="tuKzNwZ+"; dkim=fail reason="signature verification failed" (2048-bit key) header.d=google.com header.i=@google.com header.b="Yrxhb/Ib" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 04CC221D24 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:To:From:Subject:References:Mime-Version:Message-Id: In-Reply-To:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=C1NtfH+/nruCDSxuH9T1nby8uj2++aq1cL1TBmOrWus=; b=tuKzNwZ+5hnhOKr4o9pxhnIjH BE7qOFl8c9P8rln4pokLOQW+byiywPopfeV3qH4T6gsCwQ5xRcA5su5qUhCEfPmlRsH49RBIuIdA2 aLaFgH24qK153927kLmt5PIJFYUvDWABUZqCZ7K2botlJaKPuQ9qapdu7PLRvWuXQeUyQfb/WJ73D /b34LBz4cPnJ1OTkOlrY8AsAUmRfL6BuNxXPtKBN28TRgth4Tn3T05+Im5IL0gKTB6t+Dd8vSADhC UkQqS3iL3bWmWYaxKnDVdww6Upy1W6zqtd0mfUF0VMssByPaHjGFVFlJCSuBH6CRd0lt2b5iDQpfV LNNzLsQdA==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kI8hr-0006n2-MA; Tue, 15 Sep 2020 11:01:04 +0000 Received: from mail-qv1-xf49.google.com ([2607:f8b0:4864:20::f49]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kI8Uc-0000wf-F8 for linux-arm-kernel@lists.infradead.org; Tue, 15 Sep 2020 10:47:30 +0000 Received: by mail-qv1-xf49.google.com with SMTP id ct11so1850125qvb.16 for ; Tue, 15 Sep 2020 03:47:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=wzFd2Se+hSZFSU9MNWw+evLd20Vc2LmYdGji4Cqfwno=; b=Yrxhb/IbZqs0MnCRYBKrcrZAcxjNPwN8Eg0LpUCBEdK5DW8r+vfUFntl0dVniBVcur YEFy2X9rzGfmEpygefHHNWbkM+zC+z93+L25nUieVxaVXx/V7ni40oMsigqpPigpwABc LgSKRyUdCTNigBQk2RPThRzCDg+horsKnF5Nu6FbJUpGCIKaXUnFvBfpGf5qW1zp+dCf 5cFDDsegiDbKseWvr8CFcGvc5KzELjcMWNvG+poynIp/v4yLKX1dBJ7Mbrile2j4kvEZ X1ooBEnenEODgpU/DoecDxggRQiK8b6HoUtO4LmW4nIQbSzY7gTga9PU39xJYZ+bMDBK HuDQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=wzFd2Se+hSZFSU9MNWw+evLd20Vc2LmYdGji4Cqfwno=; b=dpS0wPfmPbkmvdw9aFv11qbAC4PLEkUWnsUxFUcUK1G2BgqsLa8I4BVHUKHt30L2Ud LFGOuykvdLyhRkvd9lq0JByK+ECRjIekh4vboQsH/1LznSRzjhFK+tUSfEECWZzfXQPF Ph3Li1pkB+HS+BD7vopj+u44FKYwMMWxzWPw/Lys6FnKubx5+M/lW4j4uOFZBvd7pIp8 fVMegK0uDraGqVbK29gClnjDmnEM/RcwK8GvALVRv4b04yFQgTmxLV0MBmVUfNkB7AE4 jmbVdpcml6K0gxJhZETiBfsyhVoVAKWZ+q6JdHRLl4fP9d+FpN5wClMjLOrVzwp2WFd/ wIDA== X-Gm-Message-State: AOAM531c6ZkgaOYLseLm/SRsG2LD72rBF2qLkqvRXMPUsO1LU99/lfxr oaZvJAr6KSk5wXLZKtDXEejva4gQbKc= X-Google-Smtp-Source: ABdhPJwdICVtPnTewBkU+0XX56pwR94BGjqfet77o0wGVIPdThjbg/6FNE62pNL2F9jnTFbS5JlbAv7eNUY= X-Received: from ascull.lon.corp.google.com ([2a00:79e0:d:109:4a0f:cfff:fe4a:6363]) (user=ascull job=sendgmr) by 2002:ad4:58e7:: with SMTP id di7mr1042793qvb.36.1600166835280; Tue, 15 Sep 2020 03:47:15 -0700 (PDT) Date: Tue, 15 Sep 2020 11:46:36 +0100 In-Reply-To: <20200915104643.2543892-1-ascull@google.com> Message-Id: <20200915104643.2543892-13-ascull@google.com> Mime-Version: 1.0 References: <20200915104643.2543892-1-ascull@google.com> X-Mailer: git-send-email 2.28.0.618.gf4bc123cb7-goog Subject: [PATCH v4 12/19] KVM: arm64: nVHE: Switch to hyp context for EL2 From: Andrew Scull To: kvmarm@lists.cs.columbia.edu X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200915_064723_092913_1D125D24 X-CRM114-Status: GOOD ( 20.79 ) X-Spam-Score: -7.7 (-------) X-Spam-Report: SpamAssassin version 3.4.4 on merlin.infradead.org summary: Content analysis details: (-7.7 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at https://www.dnswl.org/, no trust [2607:f8b0:4864:20:0:0:0:f49 listed in] [list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record -7.5 USER_IN_DEF_DKIM_WL From: address is in the default DKIM white-list 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature -0.1 DKIM_VALID_EF Message has a valid DKIM or DK signature from envelope-from domain -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain -0.0 DKIMWL_WL_MED DKIMwl.org - Medium sender X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arm-kernel@lists.infradead.org, kernel-team@android.com, suzuki.poulose@arm.com, maz@kernel.org, Sudeep Holla , james.morse@arm.com, Andrew Scull , catalin.marinas@arm.com, will@kernel.org, julien.thierry.kdev@gmail.com Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org Save and restore the host context when switching to and from hyp. This gives hyp its own context that the host will not see as a step towards a full trust boundary between the two. SP_EL0 and pointer authentication keys are currently shared between the host and hyp so don't need to be switched yet. Signed-off-by: Andrew Scull --- arch/arm64/kvm/hyp/include/hyp/switch.h | 2 + arch/arm64/kvm/hyp/nvhe/Makefile | 2 +- arch/arm64/kvm/hyp/nvhe/host.S | 68 ++++++++++++++++++------- arch/arm64/kvm/hyp/nvhe/hyp-main.c | 36 +++++++++++++ 4 files changed, 89 insertions(+), 19 deletions(-) create mode 100644 arch/arm64/kvm/hyp/nvhe/hyp-main.c diff --git a/arch/arm64/kvm/hyp/include/hyp/switch.h b/arch/arm64/kvm/hyp/include/hyp/switch.h index 821721b78ad9..4536b50ddc06 100644 --- a/arch/arm64/kvm/hyp/include/hyp/switch.h +++ b/arch/arm64/kvm/hyp/include/hyp/switch.h @@ -372,6 +372,8 @@ static inline bool esr_is_ptrauth_trap(u32 esr) ctxt_sys_reg(ctxt, key ## KEYHI_EL1) = __val; \ } while(0) +DECLARE_PER_CPU(struct kvm_cpu_context, kvm_hyp_ctxt); + static inline bool __hyp_handle_ptrauth(struct kvm_vcpu *vcpu) { struct kvm_cpu_context *ctxt; diff --git a/arch/arm64/kvm/hyp/nvhe/Makefile b/arch/arm64/kvm/hyp/nvhe/Makefile index ddf98eb07b9d..46c89e8c30bc 100644 --- a/arch/arm64/kvm/hyp/nvhe/Makefile +++ b/arch/arm64/kvm/hyp/nvhe/Makefile @@ -6,7 +6,7 @@ asflags-y := -D__KVM_NVHE_HYPERVISOR__ ccflags-y := -D__KVM_NVHE_HYPERVISOR__ -obj-y := timer-sr.o sysreg-sr.o debug-sr.o switch.o tlb.o hyp-init.o host.o +obj-y := timer-sr.o sysreg-sr.o debug-sr.o switch.o tlb.o hyp-init.o host.o hyp-main.o obj-y += ../vgic-v3-sr.o ../aarch32.o ../vgic-v2-cpuif-proxy.o ../entry.o \ ../fpsimd.o ../hyp-entry.o diff --git a/arch/arm64/kvm/hyp/nvhe/host.S b/arch/arm64/kvm/hyp/nvhe/host.S index 9ab7814e6114..d26e41773dc4 100644 --- a/arch/arm64/kvm/hyp/nvhe/host.S +++ b/arch/arm64/kvm/hyp/nvhe/host.S @@ -12,6 +12,55 @@ .text +SYM_FUNC_START(__host_exit) + stp x0, x1, [sp, #-16]! + + get_host_ctxt x0, x1 + + ALTERNATIVE(nop, SET_PSTATE_PAN(1), ARM64_HAS_PAN, CONFIG_ARM64_PAN) + + /* Store the host regs x2 and x3 */ + stp x2, x3, [x0, #CPU_XREG_OFFSET(2)] + + /* Retrieve the host regs x0-x1 from the stack */ + ldp x2, x3, [sp], #16 // x0, x1 + + /* Store the host regs x0-x1 and x4-x17 */ + stp x2, x3, [x0, #CPU_XREG_OFFSET(0)] + stp x4, x5, [x0, #CPU_XREG_OFFSET(4)] + stp x6, x7, [x0, #CPU_XREG_OFFSET(6)] + stp x8, x9, [x0, #CPU_XREG_OFFSET(8)] + stp x10, x11, [x0, #CPU_XREG_OFFSET(10)] + stp x12, x13, [x0, #CPU_XREG_OFFSET(12)] + stp x14, x15, [x0, #CPU_XREG_OFFSET(14)] + stp x16, x17, [x0, #CPU_XREG_OFFSET(16)] + + /* Store the host regs x18-x29, lr */ + save_callee_saved_regs x0 + + /* Save the host context pointer in x29 across the function call */ + mov x29, x0 + bl handle_trap + + /* Restore host regs x0-x17 */ + ldp x0, x1, [x29, #CPU_XREG_OFFSET(0)] + ldp x2, x3, [x29, #CPU_XREG_OFFSET(2)] + ldp x4, x5, [x29, #CPU_XREG_OFFSET(4)] + ldp x6, x7, [x29, #CPU_XREG_OFFSET(6)] + ldp x8, x9, [x29, #CPU_XREG_OFFSET(8)] + ldp x10, x11, [x29, #CPU_XREG_OFFSET(10)] + ldp x12, x13, [x29, #CPU_XREG_OFFSET(12)] + ldp x14, x15, [x29, #CPU_XREG_OFFSET(14)] + ldp x16, x17, [x29, #CPU_XREG_OFFSET(16)] + + /* Restore host regs x18-x29, lr */ + restore_callee_saved_regs x29 + + /* Do not touch any register after this! */ + eret + sb +SYM_FUNC_END(__host_exit) + SYM_FUNC_START(__hyp_do_panic) mov lr, #(PSR_F_BIT | PSR_I_BIT | PSR_A_BIT | PSR_D_BIT |\ PSR_MODE_EL1h) @@ -34,7 +83,7 @@ SYM_FUNC_END(__hyp_do_panic) /* Check for a stub HVC call */ cmp x0, #HVC_STUB_HCALL_NR - b.hs 1f + b.hs __host_exit /* * Compute the idmap address of __kvm_handle_stub_hvc and @@ -50,23 +99,6 @@ SYM_FUNC_END(__hyp_do_panic) /* x5 = __pa(x5) */ sub x5, x5, x6 br x5 - -1: - /* - * Shuffle the parameters before calling the function - * pointed to in x0. Assumes parameters in x[1,2,3]. - */ - kern_hyp_va x0 - str lr, [sp, #-16]! - mov lr, x0 - mov x0, x1 - mov x1, x2 - mov x2, x3 - blr lr - ldr lr, [sp], #16 - - eret - sb .L__vect_end\@: .if ((.L__vect_end\@ - .L__vect_start\@) > 0x80) .error "host_el1_sync_vect larger than vector entry" diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-main.c b/arch/arm64/kvm/hyp/nvhe/hyp-main.c new file mode 100644 index 000000000000..570c3896f42e --- /dev/null +++ b/arch/arm64/kvm/hyp/nvhe/hyp-main.c @@ -0,0 +1,36 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2020 - Google Inc + * Author: Andrew Scull + */ + +#include + +#include +#include +#include +#include +#include + +typedef unsigned long (*hypcall_fn_t) + (unsigned long, unsigned long, unsigned long); + +void handle_trap(struct kvm_cpu_context *host_ctxt) +{ + u64 esr = read_sysreg_el2(SYS_ESR); + hypcall_fn_t func; + unsigned long ret; + + if (ESR_ELx_EC(esr) != ESR_ELx_EC_HVC64) + hyp_panic(); + + /* + * __kvm_call_hyp takes a pointer in the host address space and + * up to three arguments. + */ + func = (hypcall_fn_t)kern_hyp_va(host_ctxt->regs.regs[0]); + ret = func(host_ctxt->regs.regs[1], + host_ctxt->regs.regs[2], + host_ctxt->regs.regs[3]); + host_ctxt->regs.regs[0] = ret; +}