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=-23.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_IN_DEF_DKIM_WL 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 CEBB3C433E1 for ; Tue, 23 Mar 2021 16:09:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9CC0E619AE for ; Tue, 23 Mar 2021 16:09:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233013AbhCWQJJ (ORCPT ); Tue, 23 Mar 2021 12:09:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42290 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233068AbhCWQIx (ORCPT ); Tue, 23 Mar 2021 12:08:53 -0400 Received: from mail-pg1-x530.google.com (mail-pg1-x530.google.com [IPv6:2607:f8b0:4864:20::530]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D4BDBC061763 for ; Tue, 23 Mar 2021 09:08:52 -0700 (PDT) Received: by mail-pg1-x530.google.com with SMTP id v186so12183933pgv.7 for ; Tue, 23 Mar 2021 09:08:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=SHe57VVrdBa1bFwRDqVR/he3mxMIJgeI52tgfT4P3Gc=; b=bpAbEHhWMOWeo1A4GPrqirZN/9Odu67rl6qzQYkPcBhF2v0cOaLOzz/5mH4x8K+wjg zDfK3y9wiLo/J1e736WNT0wTH/sdxCM6Hny902V9/vV6QQBMuu/rdJinXcMxGF4CpQBx 7OBOWoMjy+Ncu1vVunRBO9Qg1nYcDRTE4aLu748fLJhEx8ChEwmJ9GpBENIV5GcxcQuZ 9dYKQ3px22s0LxP2BrFr65YA61ormNJcdS48Omz11M/N6KMkuuGa/OLPNhf/ay5fo4J/ NJ083lVDyWryLejG3+ZiaKPYj+jOfIny839QfdrGLt3Q8UObqjiCd8CK5QYZcuMQ2wTC 3l6w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=SHe57VVrdBa1bFwRDqVR/he3mxMIJgeI52tgfT4P3Gc=; b=f18Yb87cnA5bs2IeuUQX97shBWVejd5SXXy1+q3eV8HDNM7VWzMBi0BnTyTePulGT8 BPKQ50NgSyzNnDUPHhkm5goWr512wO/NnzK6P1B0TWMQ57PPdOiiGFi06SxFvMrrCXvK C7O7vX/md13oX8sDbuCdorqz+up9DI2FC/ssBHtWdrpC6dZuV6RlyGffCpyReeZCJ/8R b2B1gdq+8v3tRuazOJOofwtZwc0NmCgl8F1MuVmTCmS0VbU6cl3H85dbcxawzPCCR//f K1cHkvZ/mM/223dUvkldvHuCGsWstVMR5DJLG2/lMfgJTuH6XxKhCdjuBMyZo27tzw0p J37A== X-Gm-Message-State: AOAM533v1jiFtTyhtTiifaLGtdbaPD57hxdvdx2dqD+At/BlG0JQpkqc 2vAYOYlQZH1yfOI43R6OASTJtSUQK9/b1g== X-Google-Smtp-Source: ABdhPJwuN7uO+rsS4FbOWNWYA10/SbOjp0fo+EXdCdz0PbJiohWrPxFdSdCMFhj1xsuG4xq0IlbwqA== X-Received: by 2002:aa7:8d04:0:b029:1ed:2328:f677 with SMTP id j4-20020aa78d040000b02901ed2328f677mr5434917pfe.26.1616515732163; Tue, 23 Mar 2021 09:08:52 -0700 (PDT) Received: from google.com (240.111.247.35.bc.googleusercontent.com. [35.247.111.240]) by smtp.gmail.com with ESMTPSA id a7sm17231034pfo.105.2021.03.23.09.08.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 23 Mar 2021 09:08:51 -0700 (PDT) Date: Tue, 23 Mar 2021 16:08:47 +0000 From: Sean Christopherson To: Cathy Avery Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, pbonzini@redhat.com, vkuznets@redhat.com, wei.huang2@amd.com Subject: Re: [PATCH] KVM: nSVM: Additions to optimizing L12 to L2 vmcb.save copies Message-ID: References: <20210317162930.28135-1-cavery@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210317162930.28135-1-cavery@redhat.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Mar 17, 2021, Cathy Avery wrote: > Extend using the vmcb12 control clean field to determine which > vmcb12.save registers were marked dirty in order to minimize > register copies by including the CR bit. > > This patch also fixes the init of last_vmcb12_gpa by using an invalid > physical address instead of 0. > > Tested: > kvm-unit-tests > kvm selftests > Fedora L1 L2 > > Signed-off-by: Cathy Avery > --- > arch/x86/kvm/svm/nested.c | 9 ++++++--- > arch/x86/kvm/svm/svm.c | 2 +- > 2 files changed, 7 insertions(+), 4 deletions(-) > > diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c > index 8523f60adb92..6f9a40e002bc 100644 > --- a/arch/x86/kvm/svm/nested.c > +++ b/arch/x86/kvm/svm/nested.c > @@ -449,9 +449,12 @@ static void nested_vmcb02_prepare_save(struct vcpu_svm *svm, struct vmcb *vmcb12 > } > > kvm_set_rflags(&svm->vcpu, vmcb12->save.rflags | X86_EFLAGS_FIXED); > - svm_set_efer(&svm->vcpu, vmcb12->save.efer); > - svm_set_cr0(&svm->vcpu, vmcb12->save.cr0); > - svm_set_cr4(&svm->vcpu, vmcb12->save.cr4); > + > + if (unlikely(new_vmcb12 || vmcb_is_dirty(vmcb12, VMCB_CR))) { > + svm_set_efer(&svm->vcpu, vmcb12->save.efer); > + svm_set_cr0(&svm->vcpu, vmcb12->save.cr0); > + svm_set_cr4(&svm->vcpu, vmcb12->save.cr4); This doesn't seem correct. Regardless of when vmcb12 was last touched, KVM still needs to set L2's state in vcpu->arch and set the correct MMU context. > + } > > svm->vcpu.arch.cr2 = vmcb12->save.cr2; > > diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c > index 271196400495..41f5cd1009ca 100644 > --- a/arch/x86/kvm/svm/svm.c > +++ b/arch/x86/kvm/svm/svm.c > @@ -1234,7 +1234,7 @@ static void init_vmcb(struct kvm_vcpu *vcpu) > svm->asid = 0; > > svm->nested.vmcb12_gpa = 0; > - svm->nested.last_vmcb12_gpa = 0; > + svm->nested.last_vmcb12_gpa = -1; INVALID_PAGE would be even better. > vcpu->arch.hflags = 0; > > if (!kvm_pause_in_guest(vcpu->kvm)) { > -- > 2.26.2 >