From mboxrd@z Thu Jan 1 00:00:00 1970 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=-6.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 036CFC433DF for ; Wed, 8 Jul 2020 09:36:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D09E2206DF for ; Wed, 8 Jul 2020 09:36:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="GtqTc5+k" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728387AbgGHJgb (ORCPT ); Wed, 8 Jul 2020 05:36:31 -0400 Received: from us-smtp-1.mimecast.com ([207.211.31.81]:46477 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728266AbgGHJg1 (ORCPT ); Wed, 8 Jul 2020 05:36:27 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1594200984; 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=0ch8uULRQ2eBy6MnhXZkwyEhlau2JCPGdpOTRmLuBXg=; b=GtqTc5+k8VtDQiYZQRfVoLy5Mo6wIgBhSx0gq2QoucI+yTId61YUKfa0Goc3+ValcMDHjx Q7ptf++iMjOtF9zLbhjuN3dljQlg5cVBT6LVlZipmMxDu6xdwka95LoYxGyKEIpf8PsYpP 56pADDwyjPhKccikXMJQs3otSNPopTk= 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-451-t0u0OeNXNfeWi3kqKl7lSw-1; Wed, 08 Jul 2020 05:36:21 -0400 X-MC-Unique: t0u0OeNXNfeWi3kqKl7lSw-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id C62C97BB1; Wed, 8 Jul 2020 09:36:19 +0000 (UTC) Received: from vitty.brq.redhat.com (unknown [10.40.195.35]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0BA3D5C3F8; Wed, 8 Jul 2020 09:36:17 +0000 (UTC) From: Vitaly Kuznetsov To: kvm@vger.kernel.org, Paolo Bonzini Cc: Sean Christopherson , Wanpeng Li , Jim Mattson , Junaid Shahid , linux-kernel@vger.kernel.org Subject: [PATCH v2 2/3] KVM: nSVM: properly call kvm_mmu_new_pgd() upon switching to guest Date: Wed, 8 Jul 2020 11:36:10 +0200 Message-Id: <20200708093611.1453618-3-vkuznets@redhat.com> In-Reply-To: <20200708093611.1453618-1-vkuznets@redhat.com> References: <20200708093611.1453618-1-vkuznets@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Undesired triple fault gets injected to L1 guest on SVM when L2 is launched with certain CR3 values. #TF is raised by mmu_check_root() check in fast_pgd_switch() and the root cause is that when kvm_set_cr3() is called from nested_prepare_vmcb_save() with NPT enabled CR3 points to a nGPA so we can't check it with kvm_is_visible_gfn(). Calling kvm_mmu_new_pgd() with L2's CR3 idea when NPT is in use seems to be wrong, an acceptable place for it seems to be kvm_init_shadow_npt_mmu(). This also matches nVMX code. Fixes: 7c390d350f8b ("kvm: x86: Add fast CR3 switch code path") Signed-off-by: Vitaly Kuznetsov --- arch/x86/include/asm/kvm_host.h | 7 ++++++- arch/x86/kvm/mmu/mmu.c | 2 ++ arch/x86/kvm/svm/nested.c | 2 +- arch/x86/kvm/x86.c | 8 +++++--- 4 files changed, 14 insertions(+), 5 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index be5363b21540..49b62f024f51 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1459,7 +1459,12 @@ int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int idt_index, int reason, bool has_error_code, u32 error_code); int kvm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0); -int kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3); +int __kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3, bool cr3_is_nested); +static inline int kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3) +{ + return __kvm_set_cr3(vcpu, cr3, false); +} + int kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4); int kvm_set_cr8(struct kvm_vcpu *vcpu, unsigned long cr8); int kvm_set_dr(struct kvm_vcpu *vcpu, int dr, unsigned long val); diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 167d12ab957a..ebf0cb3f1ce0 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -4987,6 +4987,8 @@ void kvm_init_shadow_npt_mmu(struct kvm_vcpu *vcpu, u32 cr0, u32 cr4, u32 efer, union kvm_mmu_role new_role = kvm_calc_shadow_mmu_root_page_role(vcpu, false); + __kvm_mmu_new_pgd(vcpu, nested_cr3, new_role.base, true, true); + if (new_role.as_u64 != context->mmu_role.as_u64) shadow_mmu_init_context(vcpu, cr0, cr4, efer, new_role); } diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c index e424bce13e6c..b467917a9784 100644 --- a/arch/x86/kvm/svm/nested.c +++ b/arch/x86/kvm/svm/nested.c @@ -324,7 +324,7 @@ static void nested_prepare_vmcb_save(struct vcpu_svm *svm, struct vmcb *nested_v svm_set_efer(&svm->vcpu, nested_vmcb->save.efer); svm_set_cr0(&svm->vcpu, nested_vmcb->save.cr0); svm_set_cr4(&svm->vcpu, nested_vmcb->save.cr4); - (void)kvm_set_cr3(&svm->vcpu, nested_vmcb->save.cr3); + (void)__kvm_set_cr3(&svm->vcpu, nested_vmcb->save.cr3, npt_enabled); svm->vmcb->save.cr2 = svm->vcpu.arch.cr2 = nested_vmcb->save.cr2; kvm_rax_write(&svm->vcpu, nested_vmcb->save.rax); diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 3b92db412335..3761135eb052 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1004,7 +1004,7 @@ int kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4) } EXPORT_SYMBOL_GPL(kvm_set_cr4); -int kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3) +int __kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3, bool cr3_is_nested) { bool skip_tlb_flush = false; #ifdef CONFIG_X86_64 @@ -1031,13 +1031,15 @@ int kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3) !load_pdptrs(vcpu, vcpu->arch.walk_mmu, cr3)) return 1; - kvm_mmu_new_pgd(vcpu, cr3, skip_tlb_flush, skip_tlb_flush); + if (!cr3_is_nested) + kvm_mmu_new_pgd(vcpu, cr3, skip_tlb_flush, skip_tlb_flush); + vcpu->arch.cr3 = cr3; kvm_register_mark_available(vcpu, VCPU_EXREG_CR3); return 0; } -EXPORT_SYMBOL_GPL(kvm_set_cr3); +EXPORT_SYMBOL_GPL(__kvm_set_cr3); int kvm_set_cr8(struct kvm_vcpu *vcpu, unsigned long cr8) { -- 2.25.4