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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9FB8AC433EF for ; Tue, 22 Mar 2022 17:41:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239819AbiCVRmm (ORCPT ); Tue, 22 Mar 2022 13:42:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53868 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239818AbiCVRmf (ORCPT ); Tue, 22 Mar 2022 13:42:35 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 35D608D683 for ; Tue, 22 Mar 2022 10:41:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1647970865; 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=3Gx3OZjbJEGNju3jC5LiJovVmBrlwEsjowZeisGHWak=; b=GcIzhVGTi9xLT51e8v0Q6V5s25SXVYnsmf4eySoUdYQnvtLHD2vIfBw8igLFoz+6mO9pT9 jo/GHufrrErDW2BwRzecqpm7VpN0P2mkT3/tbRacwvuSlztI/UHF2Jm+88qmqTovi+daby dW7QjrKFrGLuzCJRYHZ7NPIKsWiB/VA= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-652-mWOVEwG2OJOvvkATRwQiuQ-1; Tue, 22 Mar 2022 13:41:02 -0400 X-MC-Unique: mWOVEwG2OJOvvkATRwQiuQ-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id A04A8833959; Tue, 22 Mar 2022 17:41:01 +0000 (UTC) Received: from localhost.localdomain (unknown [10.40.194.231]) by smtp.corp.redhat.com (Postfix) with ESMTP id 714A1C07F4B; Tue, 22 Mar 2022 17:40:58 +0000 (UTC) From: Maxim Levitsky To: kvm@vger.kernel.org Cc: Ingo Molnar , Borislav Petkov , Sean Christopherson , Vitaly Kuznetsov , Paolo Bonzini , "H. Peter Anvin" , Joerg Roedel , linux-kernel@vger.kernel.org, Thomas Gleixner , Jim Mattson , x86@kernel.org, Dave Hansen , Wanpeng Li , Maxim Levitsky Subject: [PATCH v4 2/6] KVM: x86: nSVM: implement nested LBR virtualization Date: Tue, 22 Mar 2022 19:40:46 +0200 Message-Id: <20220322174050.241850-3-mlevitsk@redhat.com> In-Reply-To: <20220322174050.241850-1-mlevitsk@redhat.com> References: <20220322174050.241850-1-mlevitsk@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.85 on 10.11.54.8 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This was tested with kvm-unit-test that was developed for this purpose. Signed-off-by: Maxim Levitsky --- arch/x86/kvm/svm/nested.c | 19 +++++++++++++++++-- arch/x86/kvm/svm/svm.c | 7 +++++++ arch/x86/kvm/svm/svm.h | 1 + 3 files changed, 25 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c index 98647f5dec93..c1baa3a68ce6 100644 --- a/arch/x86/kvm/svm/nested.c +++ b/arch/x86/kvm/svm/nested.c @@ -588,8 +588,17 @@ static void nested_vmcb02_prepare_save(struct vcpu_svm *svm, struct vmcb *vmcb12 vmcb_mark_dirty(vmcb02, VMCB_DR); } - if (unlikely(vmcb01->control.virt_ext & LBR_CTL_ENABLE_MASK)) + if (unlikely(svm->lbrv_enabled && (svm->nested.ctl.virt_ext & LBR_CTL_ENABLE_MASK))) { + /* Copy LBR related registers from vmcb12, + * but make sure that we only pick LBR enable bit from the guest. + */ + svm_copy_lbrs(vmcb02, vmcb12); + vmcb02->save.dbgctl &= LBR_CTL_ENABLE_MASK; + svm_update_lbrv(&svm->vcpu); + + } else if (unlikely(vmcb01->control.virt_ext & LBR_CTL_ENABLE_MASK)) { svm_copy_lbrs(vmcb02, vmcb01); + } } static void nested_vmcb02_prepare_control(struct vcpu_svm *svm) @@ -651,6 +660,9 @@ static void nested_vmcb02_prepare_control(struct vcpu_svm *svm) vmcb02->control.virt_ext = vmcb01->control.virt_ext & LBR_CTL_ENABLE_MASK; + if (svm->lbrv_enabled) + vmcb02->control.virt_ext |= + (svm->nested.ctl.virt_ext & LBR_CTL_ENABLE_MASK); if (!nested_vmcb_needs_vls_intercept(svm)) vmcb02->control.virt_ext |= VIRTUAL_VMLOAD_VMSAVE_ENABLE_MASK; @@ -919,7 +931,10 @@ int nested_svm_vmexit(struct vcpu_svm *svm) svm_switch_vmcb(svm, &svm->vmcb01); - if (unlikely(vmcb01->control.virt_ext & LBR_CTL_ENABLE_MASK)) { + if (unlikely(svm->lbrv_enabled && (svm->nested.ctl.virt_ext & LBR_CTL_ENABLE_MASK))) { + svm_copy_lbrs(vmcb12, vmcb02); + svm_update_lbrv(vcpu); + } else if (unlikely(vmcb01->control.virt_ext & LBR_CTL_ENABLE_MASK)) { svm_copy_lbrs(vmcb01, vmcb02); svm_update_lbrv(vcpu); } diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index b3ba3bf2d95e..ec9a1dabdcc3 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -878,6 +878,10 @@ void svm_update_lbrv(struct kvm_vcpu *vcpu) bool current_enable_lbrv = !!(svm->vmcb->control.virt_ext & LBR_CTL_ENABLE_MASK); + if (unlikely(is_guest_mode(vcpu) && svm->lbrv_enabled)) + if (unlikely(svm->nested.ctl.virt_ext & LBR_CTL_ENABLE_MASK)) + enable_lbrv = true; + if (enable_lbrv == current_enable_lbrv) return; @@ -4012,6 +4016,7 @@ static void svm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu) guest_cpuid_has(vcpu, X86_FEATURE_NRIPS); svm->tsc_scaling_enabled = tsc_scaling && guest_cpuid_has(vcpu, X86_FEATURE_TSCRATEMSR); + svm->lbrv_enabled = lbrv && guest_cpuid_has(vcpu, X86_FEATURE_LBRV); svm->v_vmload_vmsave_enabled = vls && guest_cpuid_has(vcpu, X86_FEATURE_V_VMSAVE_VMLOAD); @@ -4765,6 +4770,8 @@ static __init void svm_set_cpu_caps(void) if (vls) kvm_cpu_cap_set(X86_FEATURE_V_VMSAVE_VMLOAD); + if (lbrv) + kvm_cpu_cap_set(X86_FEATURE_LBRV); /* Nested VM can receive #VMEXIT instead of triggering #GP */ kvm_cpu_cap_set(X86_FEATURE_SVME_ADDR_CHK); diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h index 75373cb24a39..aaf46b1fbf76 100644 --- a/arch/x86/kvm/svm/svm.h +++ b/arch/x86/kvm/svm/svm.h @@ -236,6 +236,7 @@ struct vcpu_svm { bool nrips_enabled : 1; bool tsc_scaling_enabled : 1; bool v_vmload_vmsave_enabled : 1; + bool lbrv_enabled : 1; u32 ldr_reg; u32 dfr_reg; -- 2.26.3