From: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
To: <pbonzini@redhat.com>, <rkrcmar@redhat.com>, <joro@8bytes.org>,
        <bp@alien8.de>, <gleb@kernel.org>, <alex.williamson@redhat.com>
CC: <kvm@vger.kernel.org>, <linux-kernel@vger.kernel.org>, <wei@redhat.com>,
        <sherry.hurwitz@amd.com>,
        Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>,
        Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Subject: [PART1 RFC v4 10/11] svm: Do not intercept CR8 when enable AVIC
Date: Thu, 7 Apr 2016 03:20:31 -0500
Message-ID: <1460017232-17429-11-git-send-email-Suravee.Suthikulpanit@amd.com>
In-Reply-To: <1460017232-17429-1-git-send-email-Suravee.Suthikulpanit@amd.com>
References: <1460017232-17429-1-git-send-email-Suravee.Suthikulpanit@amd.com>
MIME-Version: 1.0
Content-Type: text/plain
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 07 Apr 2016 08:22:07.8149
 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-Transport-CrossTenantHeadersStamped: SN1PR12MB0445
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org
Content-Length: 1906
Lines: 55

When enable AVIC:
    * Do not intercept CR8 since this should be handled by AVIC HW.
    * Also, we don't need to sync cr8/V_TPR and APIC backing page.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
---
 arch/x86/kvm/svm.c | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 74b0751..bccf6cb 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -1092,7 +1092,8 @@ static void init_vmcb(struct vcpu_svm *svm)
 	set_cr_intercept(svm, INTERCEPT_CR0_WRITE);
 	set_cr_intercept(svm, INTERCEPT_CR3_WRITE);
 	set_cr_intercept(svm, INTERCEPT_CR4_WRITE);
-	set_cr_intercept(svm, INTERCEPT_CR8_WRITE);
+	if (!svm_vcpu_avic_enabled(svm))
+		set_cr_intercept(svm, INTERCEPT_CR8_WRITE);
 
 	set_dr_intercepts(svm);
 
@@ -4069,7 +4070,8 @@ static void update_cr8_intercept(struct kvm_vcpu *vcpu, int tpr, int irr)
 {
 	struct vcpu_svm *svm = to_svm(vcpu);
 
-	if (is_guest_mode(vcpu) && (vcpu->arch.hflags & HF_VINTR_MASK))
+	if ((is_guest_mode(vcpu) && (vcpu->arch.hflags & HF_VINTR_MASK)) ||
+	     svm_vcpu_avic_enabled(svm))
 		return;
 
 	clr_cr_intercept(svm, INTERCEPT_CR8_WRITE);
@@ -4255,14 +4257,15 @@ static inline void sync_cr8_to_lapic(struct kvm_vcpu *vcpu)
 static inline void sync_lapic_to_cr8(struct kvm_vcpu *vcpu)
 {
 	struct vcpu_svm *svm = to_svm(vcpu);
-	u64 cr8;
+	struct kvm_lapic *apic = vcpu->arch.apic;
 
-	if (is_guest_mode(vcpu) && (vcpu->arch.hflags & HF_VINTR_MASK))
+	if (is_guest_mode(vcpu) && (vcpu->arch.hflags & HF_VINTR_MASK) &&
+	    svm_vcpu_avic_enabled(svm))
 		return;
 
-	cr8 = kvm_get_cr8(vcpu);
 	svm->vmcb->control.int_ctl &= ~V_TPR_MASK;
-	svm->vmcb->control.int_ctl |= cr8 & V_TPR_MASK;
+	svm->vmcb->control.int_ctl |= (kvm_apic_get_reg(apic,
+				       APIC_TASKPRI) >> 4) & V_TPR_MASK;
 }
 
 static void svm_complete_interrupts(struct vcpu_svm *svm)
-- 
1.9.1