[PART1 V5 12/13] svm: Do not intercept CR8 when enable AVIC

From: Suravee Suthikulpanit
Date: Wed May 04 2016 - 15:11:32 EST


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@xxxxxxx>
---
arch/x86/kvm/svm.c | 16 ++++++++++++----
1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index d35fd61e..721e514 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 (!kvm_vcpu_apicv_active(&svm->vcpu))
+ set_cr_intercept(svm, INTERCEPT_CR8_WRITE);

set_dr_intercepts(svm);

@@ -4077,11 +4078,17 @@ static void svm_set_irq(struct kvm_vcpu *vcpu)
SVM_EVTINJ_VALID | SVM_EVTINJ_TYPE_INTR;
}

+static inline bool svm_in_nested_interrupt_shadow(struct kvm_vcpu *vcpu)
+{
+ return is_guest_mode(vcpu) && (vcpu->arch.hflags & HF_VINTR_MASK);
+}
+
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 (svm_in_nested_interrupt_shadow(vcpu) ||
+ kvm_vcpu_apicv_active(vcpu))
return;

clr_cr_intercept(svm, INTERCEPT_CR8_WRITE);
@@ -4254,7 +4261,7 @@ static inline void sync_cr8_to_lapic(struct kvm_vcpu *vcpu)
{
struct vcpu_svm *svm = to_svm(vcpu);

- if (is_guest_mode(vcpu) && (vcpu->arch.hflags & HF_VINTR_MASK))
+ if (svm_in_nested_interrupt_shadow(vcpu))
return;

if (!is_cr_intercept(svm, INTERCEPT_CR8_WRITE)) {
@@ -4268,7 +4275,8 @@ static inline void sync_lapic_to_cr8(struct kvm_vcpu *vcpu)
struct vcpu_svm *svm = to_svm(vcpu);
u64 cr8;

- if (is_guest_mode(vcpu) && (vcpu->arch.hflags & HF_VINTR_MASK))
+ if (svm_in_nested_interrupt_shadow(vcpu) ||
+ kvm_vcpu_apicv_active(vcpu))
return;

cr8 = kvm_get_cr8(vcpu);
--
1.9.1