KVM: vmx: clear pending interrupts on KVM_SET_LAPIC

Pending interrupts might be in the PI descriptor when the
LAPIC is restored from an external state; we do not want
them to be injected.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/lapic.c

@@ -2204,8 +2204,7 @@ int kvm_apic_set_state(struct kvm_vcpu *vcpu, struct kvm_lapic_state *s)
 				1 : count_vectors(apic->regs + APIC_ISR);
 	apic->highest_isr_cache = -1;
 	if (vcpu->arch.apicv_active) {
-		if (kvm_x86_ops->apicv_post_state_restore)
-			kvm_x86_ops->apicv_post_state_restore(vcpu);
+		kvm_x86_ops->apicv_post_state_restore(vcpu);
 		kvm_x86_ops->hwapic_irr_update(vcpu,
 				apic_find_highest_irr(apic));
 		kvm_x86_ops->hwapic_isr_update(vcpu,

arch/x86/kvm/vmx.c

@@ -8749,6 +8749,14 @@ static void vmx_load_eoi_exitmap(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)
 	vmcs_write64(EOI_EXIT_BITMAP3, eoi_exit_bitmap[3]);
 }
 
+static void vmx_apicv_post_state_restore(struct kvm_vcpu *vcpu)
+{
+	struct vcpu_vmx *vmx = to_vmx(vcpu);
+
+	pi_clear_on(&vmx->pi_desc);
+	memset(vmx->pi_desc.pir, 0, sizeof(vmx->pi_desc.pir));
+}
+
 static void vmx_complete_atomic_exit(struct vcpu_vmx *vmx)
 {
 	u32 exit_intr_info;
@@ -11574,6 +11582,7 @@ static struct kvm_x86_ops vmx_x86_ops __ro_after_init = {
 	.get_enable_apicv = vmx_get_enable_apicv,
 	.refresh_apicv_exec_ctrl = vmx_refresh_apicv_exec_ctrl,
 	.load_eoi_exitmap = vmx_load_eoi_exitmap,
+	.apicv_post_state_restore = vmx_apicv_post_state_restore,
 	.hwapic_irr_update = vmx_hwapic_irr_update,
 	.hwapic_isr_update = vmx_hwapic_isr_update,
 	.sync_pir_to_irr = vmx_sync_pir_to_irr,