[PART1 RFC v3 11/12] svm: Do not intercept CR8 when enable AVIC

[Suravee Suthikulpanit]

When enable AVIC:
    * Do not intercept CR8 since this should be handled by AVIC HW.
    * Also update TPR in APIC backing page when syncing CR8 before VMRUN

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpa...@amd.com>
---
 arch/x86/kvm/svm.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index ba84d57..d5418c3 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -984,6 +984,8 @@ static __init int svm_hardware_setup(void)
 
        if (avic) {
                printk(KERN_INFO "kvm: AVIC enabled\n");
+
+               svm_x86_ops.update_cr8_intercept = NULL;
        } else {
                svm_x86_ops.deliver_posted_interrupt = NULL;
        }
@@ -1097,7 +1099,8 @@ 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);
 
@@ -4080,7 +4083,8 @@ 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);
@@ -4271,9 +4275,12 @@ static inline void sync_lapic_to_cr8(struct kvm_vcpu 
*vcpu)
        if (is_guest_mode(vcpu) && (vcpu->arch.hflags & HF_VINTR_MASK))
                return;
 
-       cr8 = kvm_get_cr8(vcpu);
+       cr8 = kvm_get_cr8(vcpu) & V_TPR_MASK;
        svm->vmcb->control.int_ctl &= ~V_TPR_MASK;
-       svm->vmcb->control.int_ctl |= cr8 & V_TPR_MASK;
+       svm->vmcb->control.int_ctl |= cr8;
+
+       if (svm_vcpu_avic_enabled(svm))
+               kvm_lapic_set_reg(svm->vcpu.arch.apic, APIC_TASKPRI, (u32)cr8 
<< 4);
 }
 
 static void svm_complete_interrupts(struct vcpu_svm *svm)
-- 
1.9.1