From patchwork Thu Feb 4 14:54:33 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paolo Bonzini X-Patchwork-Id: 12067763 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EEFC3C433E9 for ; Thu, 4 Feb 2021 16:41:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ACC8064DF5 for ; Thu, 4 Feb 2021 16:41:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237225AbhBDQlf (ORCPT ); Thu, 4 Feb 2021 11:41:35 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:36969 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236997AbhBDO4T (ORCPT ); Thu, 4 Feb 2021 09:56:19 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1612450492; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=8iBj0wuM07dI7iQONn5zv06J3XRXvw3wPfuXWUn8/9g=; b=dwzOJTdtiYjUJW0ucQz/kipc28HWwGVvznXpwIBmiy8regFnG2NiO+pjqt/Uw9u/8PAeEx nxlDGDlGaood07HDs2g4u2fvJ0ICwvbFlkAoAE6eExC5XlzDNbXvapYewoWGg5+LTt3Ny1 fZTcn2+SAicKHzH0Buc65cvq66UW+Y8= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-432-p7j8p1xbPkCObg9Myn3T9A-1; Thu, 04 Feb 2021 09:54:49 -0500 X-MC-Unique: p7j8p1xbPkCObg9Myn3T9A-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 45986107ACE4; Thu, 4 Feb 2021 14:54:35 +0000 (UTC) Received: from virtlab511.virt.lab.eng.bos.redhat.com (virtlab511.virt.lab.eng.bos.redhat.com [10.19.152.198]) by smtp.corp.redhat.com (Postfix) with ESMTP id EA49C60BE2; Thu, 4 Feb 2021 14:54:34 +0000 (UTC) From: Paolo Bonzini To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: seanjc@google.com Subject: [PATCH v2 2/2] KVM: x86: move kvm_inject_gp up from kvm_set_dr to callers Date: Thu, 4 Feb 2021 09:54:33 -0500 Message-Id: <20210204145433.243806-3-pbonzini@redhat.com> In-Reply-To: <20210204145433.243806-1-pbonzini@redhat.com> References: <20210204145433.243806-1-pbonzini@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Push the injection of #GP up to the callers, since they can just use kvm_complete_insn_gp and __kvm_set_dr pretty much returns what the callers can pass to kvm_complete_insn_gp. Therefore, rename __kvm_set_dr to kvm_set_dr and drop the kvm_set_dr wrapper. This also allows nested VMX code, which really wanted to use __kvm_set_dr, to use the right function. While at it, remove the kvm_require_dr() check from the SVM handler. The APM states: All normal exception checks take precedence over the SVM intercepts. and that includes the CR4.DE=1 #UD. Signed-off-by: Paolo Bonzini --- arch/x86/kvm/svm/svm.c | 13 +++++-------- arch/x86/kvm/vmx/vmx.c | 17 ++++++++++------- arch/x86/kvm/x86.c | 19 +++++-------------- 3 files changed, 20 insertions(+), 29 deletions(-) diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 4141caea857a..ea1bd96a9804 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -2619,6 +2619,7 @@ static int dr_interception(struct vcpu_svm *svm) { int reg, dr; unsigned long val; + int err = 0; if (svm->vcpu.guest_debug == 0) { /* @@ -2636,20 +2637,16 @@ static int dr_interception(struct vcpu_svm *svm) reg = svm->vmcb->control.exit_info_1 & SVM_EXITINFO_REG_MASK; dr = svm->vmcb->control.exit_code - SVM_EXIT_READ_DR0; - if (dr >= 16) { /* mov to DRn */ - if (!kvm_require_dr(&svm->vcpu, dr - 16)) - return 1; + dr -= 16; val = kvm_register_read(&svm->vcpu, reg); - kvm_set_dr(&svm->vcpu, dr - 16, val); + err = kvm_set_dr(&svm->vcpu, dr, val); } else { - if (!kvm_require_dr(&svm->vcpu, dr)) - return 1; kvm_get_dr(&svm->vcpu, dr, &val); kvm_register_write(&svm->vcpu, reg, val); } - return kvm_skip_emulated_instruction(&svm->vcpu); + return kvm_complete_insn_gp(&svm->vcpu, err); } static int cr8_write_interception(struct vcpu_svm *svm) diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 049fbbd0aa1a..13898871e5b0 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -5095,6 +5095,7 @@ static int handle_dr(struct kvm_vcpu *vcpu) { unsigned long exit_qualification; int dr, dr7, reg; + int err = 1; exit_qualification = vmx_get_exit_qual(vcpu); dr = exit_qualification & DEBUG_REG_ACCESS_NUM; @@ -5103,9 +5104,9 @@ static int handle_dr(struct kvm_vcpu *vcpu) if (!kvm_require_dr(vcpu, dr)) return 1; - /* Do not handle if the CPL > 0, will trigger GP on re-entry */ - if (!kvm_require_cpl(vcpu, 0)) - return 1; + if (kvm_x86_ops.get_cpl(vcpu) > 0) + goto out; + dr7 = vmcs_readl(GUEST_DR7); if (dr7 & DR7_GD) { /* @@ -5144,11 +5145,13 @@ static int handle_dr(struct kvm_vcpu *vcpu) kvm_get_dr(vcpu, dr, &val); kvm_register_write(vcpu, reg, val); - } else - if (kvm_set_dr(vcpu, dr, kvm_register_readl(vcpu, reg))) - return 1; + err = 0; + } else { + err = kvm_set_dr(vcpu, dr, kvm_register_readl(vcpu, reg)); + } - return kvm_skip_emulated_instruction(vcpu); +out: + return kvm_complete_insn_gp(vcpu, err); } static void vmx_sync_dirty_debug_regs(struct kvm_vcpu *vcpu) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index dcb67429b75d..baa90ae76ba5 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1143,7 +1143,7 @@ static u64 kvm_dr6_fixed(struct kvm_vcpu *vcpu) return fixed; } -static int __kvm_set_dr(struct kvm_vcpu *vcpu, int dr, unsigned long val) +int kvm_set_dr(struct kvm_vcpu *vcpu, int dr, unsigned long val) { size_t size = ARRAY_SIZE(vcpu->arch.db); @@ -1156,13 +1156,13 @@ static int __kvm_set_dr(struct kvm_vcpu *vcpu, int dr, unsigned long val) case 4: case 6: if (!kvm_dr6_valid(val)) - return -1; /* #GP */ + return 1; /* #GP */ vcpu->arch.dr6 = (val & DR6_VOLATILE) | kvm_dr6_fixed(vcpu); break; case 5: default: /* 7 */ if (!kvm_dr7_valid(val)) - return -1; /* #GP */ + return 1; /* #GP */ vcpu->arch.dr7 = (val & DR7_VOLATILE) | DR7_FIXED_1; kvm_update_dr7(vcpu); break; @@ -1170,15 +1170,6 @@ static int __kvm_set_dr(struct kvm_vcpu *vcpu, int dr, unsigned long val) return 0; } - -int kvm_set_dr(struct kvm_vcpu *vcpu, int dr, unsigned long val) -{ - if (__kvm_set_dr(vcpu, dr, val)) { - kvm_inject_gp(vcpu, 0); - return 1; - } - return 0; -} EXPORT_SYMBOL_GPL(kvm_set_dr); void kvm_get_dr(struct kvm_vcpu *vcpu, int dr, unsigned long *val) @@ -6619,7 +6610,7 @@ static int emulator_set_dr(struct x86_emulate_ctxt *ctxt, int dr, unsigned long value) { - return __kvm_set_dr(emul_to_vcpu(ctxt), dr, value); + return kvm_set_dr(emul_to_vcpu(ctxt), dr, value); } static u64 mk_cr_64(u64 curr_cr, u32 new_val) @@ -8664,7 +8655,7 @@ static void enter_smm(struct kvm_vcpu *vcpu) dt.address = dt.size = 0; static_call(kvm_x86_set_idt)(vcpu, &dt); - __kvm_set_dr(vcpu, 7, DR7_FIXED_1); + kvm_set_dr(vcpu, 7, DR7_FIXED_1); cs.selector = (vcpu->arch.smbase >> 4) & 0xffff; cs.base = vcpu->arch.smbase;