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 BC2A2C433EF for ; Tue, 1 Mar 2022 14:37:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235391AbiCAOiV (ORCPT ); Tue, 1 Mar 2022 09:38:21 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32904 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235358AbiCAOiD (ORCPT ); Tue, 1 Mar 2022 09:38:03 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 5AEAA52E56 for ; Tue, 1 Mar 2022 06:37:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1646145441; 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=j8z/etQ1X1wP3zp1s59RBUFr/gRZ4/Oh3FWIdTLhn2E=; b=Mwp1AXR7UpGKQ2lgDk2V+ctjlQFZCiLzKoPAu3Cd5yrlBDCHGDI4h6Cd4J3NruTn6e4FVa j670HZriUOpf7Efad8BE5JqbGUW5svY9QRBkexrWbIui+irkyEVjbgQ2rhgIgFCCK6TPu2 SXIcwtVB4ZX7PGHfnTQk2pwO+ltxhcQ= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-623-bEX0gBMWNpqdenSo7mFRjQ-1; Tue, 01 Mar 2022 09:37:18 -0500 X-MC-Unique: bEX0gBMWNpqdenSo7mFRjQ-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id A25B2835DE4; Tue, 1 Mar 2022 14:37:16 +0000 (UTC) Received: from localhost.localdomain (unknown [10.40.195.190]) by smtp.corp.redhat.com (Postfix) with ESMTP id 9B41D842C9; Tue, 1 Mar 2022 14:37:12 +0000 (UTC) From: Maxim Levitsky To: kvm@vger.kernel.org Cc: Ingo Molnar , Dave Hansen , Sean Christopherson , Borislav Petkov , "H. Peter Anvin" , Thomas Gleixner , Jim Mattson , x86@kernel.org, Vitaly Kuznetsov , Joerg Roedel , linux-kernel@vger.kernel.org, Paolo Bonzini , Wanpeng Li , Maxim Levitsky Subject: [PATCH v3 2/7] KVM: x86: nSVM: implement nested LBR virtualization Date: Tue, 1 Mar 2022 16:36:45 +0200 Message-Id: <20220301143650.143749-3-mlevitsk@redhat.com> In-Reply-To: <20220301143650.143749-1-mlevitsk@redhat.com> References: <20220301143650.143749-1-mlevitsk@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 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 | 21 +++++++++++++++++++-- arch/x86/kvm/svm/svm.c | 8 ++++++++ arch/x86/kvm/svm/svm.h | 1 + 3 files changed, 28 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c index d026f89ee94e6..12e856bfce408 100644 --- a/arch/x86/kvm/svm/nested.c +++ b/arch/x86/kvm/svm/nested.c @@ -565,8 +565,19 @@ static void nested_vmcb02_prepare_save(struct vcpu_svm *svm, struct vmcb *vmcb12 vmcb_mark_dirty(svm->vmcb, VMCB_DR); } - if (unlikely(svm->vmcb01.ptr->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(vmcb12, svm->vmcb); + svm->vmcb->save.dbgctl &= LBR_CTL_ENABLE_MASK; + svm_update_lbrv(&svm->vcpu); + + } else if (unlikely(svm->vmcb01.ptr->control.virt_ext & LBR_CTL_ENABLE_MASK)) { svm_copy_lbrs(svm->vmcb01.ptr, svm->vmcb); + } } static void nested_vmcb02_prepare_control(struct vcpu_svm *svm) @@ -626,6 +637,9 @@ static void nested_vmcb02_prepare_control(struct vcpu_svm *svm) svm->vmcb->control.virt_ext = svm->vmcb01.ptr->control.virt_ext & LBR_CTL_ENABLE_MASK; + if (svm->lbrv_enabled) + svm->vmcb->control.virt_ext |= + (svm->nested.ctl.virt_ext & LBR_CTL_ENABLE_MASK); nested_svm_transition_tlb_flush(vcpu); @@ -889,7 +903,10 @@ int nested_svm_vmexit(struct vcpu_svm *svm) svm_switch_vmcb(svm, &svm->vmcb01); - if (unlikely(svm->vmcb->control.virt_ext & LBR_CTL_ENABLE_MASK)) { + if (unlikely(svm->lbrv_enabled && (svm->nested.ctl.virt_ext & LBR_CTL_ENABLE_MASK))) { + svm_copy_lbrs(svm->nested.vmcb02.ptr, vmcb12); + svm_update_lbrv(vcpu); + } else if (unlikely(svm->vmcb->control.virt_ext & LBR_CTL_ENABLE_MASK)) { svm_copy_lbrs(svm->nested.vmcb02.ptr, svm->vmcb); svm_update_lbrv(vcpu); } diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index aa6c04d15d2a7..8d87f84f93f30 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -888,6 +888,10 @@ 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; @@ -3998,6 +4002,7 @@ 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_recalc_instruction_intercepts(vcpu, svm); @@ -4748,6 +4753,9 @@ static __init void svm_set_cpu_caps(void) if (tsc_scaling) kvm_cpu_cap_set(X86_FEATURE_TSCRATEMSR); + 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 2d0487968cba4..86dc1f997e01d 100644 --- a/arch/x86/kvm/svm/svm.h +++ b/arch/x86/kvm/svm/svm.h @@ -232,6 +232,7 @@ struct vcpu_svm { /* cached guest cpuid flags for faster access */ bool nrips_enabled : 1; bool tsc_scaling_enabled : 1; + bool lbrv_enabled : 1; u32 ldr_reg; u32 dfr_reg; -- 2.26.3