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=-8.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 69687C31E45 for ; Thu, 13 Jun 2019 17:06:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3D6642063F for ; Thu, 13 Jun 2019 17:06:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="rOHyuLkO" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2393432AbfFMRGd (ORCPT ); Thu, 13 Jun 2019 13:06:33 -0400 Received: from mail-wm1-f68.google.com ([209.85.128.68]:34866 "EHLO mail-wm1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2393300AbfFMRD6 (ORCPT ); Thu, 13 Jun 2019 13:03:58 -0400 Received: by mail-wm1-f68.google.com with SMTP id c6so10920533wml.0; Thu, 13 Jun 2019 10:03:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:to:cc:subject:date:message-id:in-reply-to:references; bh=1xszuqo4jzQZnosE9CJxZHoV5wm53oaDFI2DV1TesBo=; b=rOHyuLkOK6v3UzpN3AA29V7Kfl/OJSWuNYA4ARIOa7bDsgIZqCvZMHMqof75DDEPl+ PdffCnOtMcHt3URvKW5pgaGwD4D6cZG0YZFeGnHipps6kyc9qSt5h6qavRtMeYn+yK3I EgAe3FZyDCF1S5g2HzIU1JHbc2iuEjQiNNlkl2FKUnR5aQcFJKplNyPoxX5y2DDMyMr/ IC/2yfbc6Y5w7PNqSt7HtFXamiCP/Pq+PIF89lKxCA+GXudhn75eMnxg+/amTsLiFShZ 7kj4xxTMj3IDCraXFN0kF61G+9R+Ac2uIkgKeUTzjlvBzseq/+MKUfMTdo4TH2wo+HiM Fx7A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:date:message-id :in-reply-to:references; bh=1xszuqo4jzQZnosE9CJxZHoV5wm53oaDFI2DV1TesBo=; b=LDoQay4C+NVD/kbfaZhEI+5Cl/gezqeAHFx03+VxQRXg3pCJy5fIsoh2h3HhJAqb1V YRCMnhHa8eNFyBIJyV5PVQ+gN1zkEgIGIHym/zB+HuQChjY4/mWmcuv/lt4q+ex41jfI A/mPV8ndWL+O1gSvqkhsCeZ9y1tPTB/wocLS06wL1kLR+D/EuCLmS3HK7EzjORm1TzPX YBatRNwQ+IZaUJAjgpyrnh8Vv+y+l/OxFfRbxVRMdnalXTdtteeHXq0qBwXZj/WmrwNN fjbyho3Z92R+z75p8RNEKpcXNKR5M4+nMZAIph+K4XO2niqPULp85/o1TJXv8hPE7u9P f6zQ== X-Gm-Message-State: APjAAAVvzNeSYst0TN6G7LgZq2ca/1DSOIcuidcgi1fsktI1rGfc8PJN MEJklzhgZnJAB1GRCuBOIKspoaLq X-Google-Smtp-Source: APXvYqwl36GFEvwlwotdqp0CKotuFjzLk3OdGhjgV6j1CjwJ9zMJ3XB09480XrrTPKzrc3/f4DjW8A== X-Received: by 2002:a1c:6242:: with SMTP id w63mr4867248wmb.161.1560445436772; Thu, 13 Jun 2019 10:03:56 -0700 (PDT) Received: from 640k.localdomain ([93.56.166.5]) by smtp.gmail.com with ESMTPSA id a10sm341856wrx.17.2019.06.13.10.03.56 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 13 Jun 2019 10:03:56 -0700 (PDT) From: Paolo Bonzini To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: Sean Christopherson , vkuznets@redhat.com Subject: [PATCH 23/43] KVM: nVMX: Don't speculatively write virtual-APIC page address Date: Thu, 13 Jun 2019 19:03:09 +0200 Message-Id: <1560445409-17363-24-git-send-email-pbonzini@redhat.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1560445409-17363-1-git-send-email-pbonzini@redhat.com> References: <1560445409-17363-1-git-send-email-pbonzini@redhat.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Sean Christopherson The VIRTUAL_APIC_PAGE_ADDR in vmcs02 is guaranteed to be updated before it is consumed by hardware, either in nested_vmx_enter_non_root_mode() or via the KVM_REQ_GET_VMCS12_PAGES callback. Avoid an extra VMWRITE and only stuff a bad value into vmcs02 when mapping vmcs12's address fails. This also eliminates the need for extra comments to connect the dots between prepare_vmcs02_early() and nested_get_vmcs12_pages(). Signed-off-by: Sean Christopherson Signed-off-by: Paolo Bonzini --- arch/x86/kvm/vmx/nested.c | 21 ++++++++------------- 1 file changed, 8 insertions(+), 13 deletions(-) diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 0f4cb473bd36..d055bbc5cbde 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -2039,20 +2039,13 @@ static void prepare_vmcs02_early(struct vcpu_vmx *vmx, struct vmcs12 *vmcs12) exec_control &= ~CPU_BASED_TPR_SHADOW; exec_control |= vmcs12->cpu_based_vm_exec_control; - /* - * Write an illegal value to VIRTUAL_APIC_PAGE_ADDR. Later, if - * nested_get_vmcs12_pages can't fix it up, the illegal value - * will result in a VM entry failure. - */ - if (exec_control & CPU_BASED_TPR_SHADOW) { - vmcs_write64(VIRTUAL_APIC_PAGE_ADDR, -1ull); + if (exec_control & CPU_BASED_TPR_SHADOW) vmcs_write32(TPR_THRESHOLD, vmcs12->tpr_threshold); - } else { #ifdef CONFIG_X86_64 + else exec_control |= CPU_BASED_CR8_LOAD_EXITING | CPU_BASED_CR8_STORE_EXITING; #endif - } /* * A vmexit (to either L1 hypervisor or L0 userspace) is always needed @@ -2861,10 +2854,6 @@ static void nested_get_vmcs12_pages(struct kvm_vcpu *vcpu) if (nested_cpu_has(vmcs12, CPU_BASED_TPR_SHADOW)) { map = &vmx->nested.virtual_apic_map; - /* - * If translation failed, VM entry will fail because - * prepare_vmcs02 set VIRTUAL_APIC_PAGE_ADDR to -1ull. - */ if (!kvm_vcpu_map(vcpu, gpa_to_gfn(vmcs12->virtual_apic_page_addr), map)) { vmcs_write64(VIRTUAL_APIC_PAGE_ADDR, pfn_to_hpa(map->pfn)); } else if (nested_cpu_has(vmcs12, CPU_BASED_CR8_LOAD_EXITING) && @@ -2880,6 +2869,12 @@ static void nested_get_vmcs12_pages(struct kvm_vcpu *vcpu) */ vmcs_clear_bits(CPU_BASED_VM_EXEC_CONTROL, CPU_BASED_TPR_SHADOW); + } else { + /* + * Write an illegal value to VIRTUAL_APIC_PAGE_ADDR to + * force VM-Entry to fail. + */ + vmcs_write64(VIRTUAL_APIC_PAGE_ADDR, -1ull); } } -- 1.8.3.1