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=-13.3 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, UNWANTED_LANGUAGE_BODY 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 C45E1C433F5 for ; Fri, 3 Sep 2021 10:21:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ADBA060200 for ; Fri, 3 Sep 2021 10:21:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349059AbhICKWY (ORCPT ); Fri, 3 Sep 2021 06:22:24 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:33419 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1349099AbhICKWT (ORCPT ); Fri, 3 Sep 2021 06:22:19 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1630664479; 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=zMp847RRFjTaLRpSBQ+UrPlhlb53S4+7AKOB2HhMWGs=; b=FnbazSFsQQVD0f/DgN/WK9Gtc6W6XTp630W3kzmmzGi19jvvKGgQPWivFUqhOQzNEmUeuX je1yMfLktREYFZWzWzJ0ktyKt8OwxmemiLJ1NrZDg8iCnBclxhXa0COpMWRa/a6mPIER3U n7wfT1rkDsDS0J3Uh+8pQvDsCUH1hGI= 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-120-73BoPP0gMM-fuSAT5W9dOQ-1; Fri, 03 Sep 2021 06:21:18 -0400 X-MC-Unique: 73BoPP0gMM-fuSAT5W9dOQ-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 0F138501E0; Fri, 3 Sep 2021 10:21:17 +0000 (UTC) Received: from localhost.localdomain (unknown [10.39.193.161]) by smtp.corp.redhat.com (Postfix) with ESMTP id 8A2E15D9C6; Fri, 3 Sep 2021 10:21:13 +0000 (UTC) From: Emanuele Giuseppe Esposito To: kvm@vger.kernel.org Cc: Paolo Bonzini , Maxim Levitsky , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86@kernel.org, "H. Peter Anvin" , linux-kernel@vger.kernel.org, Emanuele Giuseppe Esposito Subject: [RFC PATCH 2/3] nSVM: introduce smv->nested.save to cache save area fields Date: Fri, 3 Sep 2021 12:20:38 +0200 Message-Id: <20210903102039.55422-3-eesposit@redhat.com> In-Reply-To: <20210903102039.55422-1-eesposit@redhat.com> References: <20210903102039.55422-1-eesposit@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is useful in next patch, to avoid having temporary copies of vmcb12 registers and passing them manually. Right now, instead of blindly copying everything, we just copy EFER, CR0, CR3, CR4, DR6 and DR7. If more fields will need to be added, it will be more obvious to see that they must be added in copy_vmcb_save_area, otherwise the checks will fail. Signed-off-by: Emanuele Giuseppe Esposito --- arch/x86/kvm/svm/nested.c | 24 ++++++++++++++++++++++++ arch/x86/kvm/svm/svm.c | 1 + arch/x86/kvm/svm/svm.h | 3 +++ 3 files changed, 28 insertions(+) diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c index d2fe65e2a7a4..2491c77203c7 100644 --- a/arch/x86/kvm/svm/nested.c +++ b/arch/x86/kvm/svm/nested.c @@ -194,6 +194,22 @@ static void copy_vmcb_control_area(struct vmcb_control_area *dst, dst->pause_filter_thresh = from->pause_filter_thresh; } +static void copy_vmcb_save_area(struct vmcb_save_area *dst, + struct vmcb_save_area *from) +{ + /* + * Copy only necessary fields, as we need them + * to avoid TOC/TOU races. + */ + dst->efer = from->efer; + dst->cr0 = from->cr0; + dst->cr3 = from->cr3; + dst->cr4 = from->cr4; + + dst->dr6 = from->dr6; + dst->dr7 = from->dr7; +} + static bool nested_svm_vmrun_msrpm(struct vcpu_svm *svm) { /* @@ -313,6 +329,12 @@ void nested_load_control_from_vmcb12(struct vcpu_svm *svm, svm->nested.ctl.iopm_base_pa &= ~0x0fffULL; } +void nested_load_save_from_vmcb12(struct vcpu_svm *svm, + struct vmcb_save_area *save) +{ + copy_vmcb_save_area(&svm->nested.save, save); +} + /* * Synchronize fields that are written by the processor, so that * they can be copied back into the vmcb12. @@ -647,6 +669,7 @@ int nested_svm_vmrun(struct kvm_vcpu *vcpu) return -EINVAL; nested_load_control_from_vmcb12(svm, &vmcb12->control); + nested_load_save_from_vmcb12(svm, &vmcb12->save); if (!nested_vmcb_valid_sregs(vcpu, &vmcb12->save) || !nested_vmcb_check_controls(vcpu, &svm->nested.ctl)) { @@ -1385,6 +1408,7 @@ static int svm_set_nested_state(struct kvm_vcpu *vcpu, svm_copy_vmrun_state(&svm->vmcb01.ptr->save, save); nested_load_control_from_vmcb12(svm, ctl); + nested_load_save_from_vmcb12(svm, save); svm_switch_vmcb(svm, &svm->nested.vmcb02); nested_vmcb02_prepare_control(svm); diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 69639f9624f5..169b930322ef 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -4386,6 +4386,7 @@ static int svm_leave_smm(struct kvm_vcpu *vcpu, const char *smstate) vmcb12 = map.hva; nested_load_control_from_vmcb12(svm, &vmcb12->control); + nested_load_save_from_vmcb12(svm, &vmcb12->save); ret = enter_svm_guest_mode(vcpu, vmcb12_gpa, vmcb12); kvm_vcpu_unmap(vcpu, &map, true); diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h index bd0fe94c2920..6d12814cf64c 100644 --- a/arch/x86/kvm/svm/svm.h +++ b/arch/x86/kvm/svm/svm.h @@ -119,6 +119,7 @@ struct svm_nested_state { /* cache for control fields of the guest */ struct vmcb_control_area ctl; + struct vmcb_save_area save; bool initialized; }; @@ -484,6 +485,8 @@ int nested_svm_check_exception(struct vcpu_svm *svm, unsigned nr, int nested_svm_exit_special(struct vcpu_svm *svm); void nested_load_control_from_vmcb12(struct vcpu_svm *svm, struct vmcb_control_area *control); +void nested_load_save_from_vmcb12(struct vcpu_svm *svm, + struct vmcb_save_area *save); void nested_sync_control_from_vmcb02(struct vcpu_svm *svm); void nested_vmcb02_compute_g_pat(struct vcpu_svm *svm); void svm_switch_vmcb(struct vcpu_svm *svm, struct kvm_vmcb_info *target_vmcb); -- 2.27.0