1 files changed, 27 insertions, 4 deletions

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index ee2ee83f3c48..61bb2cb51215 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -1502,6 +1502,27 @@ static void svm_set_irq(struct kvm_vcpu *vcpu, int irq)
         svm_inject_irq(svm, irq);
 }
 
+static void update_cr8_intercept(struct kvm_vcpu *vcpu)
+{
+        struct vcpu_svm *svm = to_svm(vcpu);
+        struct vmcb *vmcb = svm->vmcb;
+        int max_irr, tpr;
+
+        if (!irqchip_in_kernel(vcpu->kvm) || vcpu->arch.apic->vapic_addr)
+                return;
+
+        vmcb->control.intercept_cr_write &= ~INTERCEPT_CR8_MASK;
+
+        max_irr = kvm_lapic_find_highest_irr(vcpu);
+        if (max_irr == -1)
+                return;
+
+        tpr = kvm_lapic_get_cr8(vcpu) << 4;
+
+        if (tpr >= (max_irr & 0xf0))
+                vmcb->control.intercept_cr_write |= INTERCEPT_CR8_MASK;
+}
+
 static void svm_intr_assist(struct kvm_vcpu *vcpu)
 {
         struct vcpu_svm *svm = to_svm(vcpu);
@@ -1514,14 +1535,14 @@ static void svm_intr_assist(struct kvm_vcpu *vcpu)
                               SVM_EVTINJ_VEC_MASK;
                 vmcb->control.exit_int_info = 0;
                 svm_inject_irq(svm, intr_vector);
-                return;
+                goto out;
         }
 
         if (vmcb->control.int_ctl & V_IRQ_MASK)
-                return;
+                goto out;
 
         if (!kvm_cpu_has_interrupt(vcpu))
-                return;
+                goto out;
 
         if (!(vmcb->save.rflags & X86_EFLAGS_IF) ||
             (vmcb->control.int_state & SVM_INTERRUPT_SHADOW_MASK) ||
@@ -1529,12 +1550,14 @@ static void svm_intr_assist(struct kvm_vcpu *vcpu)
                 /* unable to deliver irq, set pending irq */
                 vmcb->control.intercept |= (1ULL << INTERCEPT_VINTR);
                 svm_inject_irq(svm, 0x0);
-                return;
+                goto out;
         }
         /* Okay, we can deliver the interrupt: grab it and update PIC state. */
         intr_vector = kvm_cpu_get_interrupt(vcpu);
         svm_inject_irq(svm, intr_vector);
         kvm_timer_intr_post(vcpu, intr_vector);
+out:
+        update_cr8_intercept(vcpu);
 }
 
 static void kvm_reput_irq(struct vcpu_svm *svm)