KVM: IRQ ACK notifier should be used with in-kernel irqchip

Also remove unnecessary parameter of unregister irq ack notifier.
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

include/linux/kvm_host.h

@@ -316,8 +316,7 @@ void kvm_set_irq(struct kvm *kvm, int irq_source_id, int irq, int level);
 void kvm_notify_acked_irq(struct kvm *kvm, unsigned gsi);
 void kvm_register_irq_ack_notifier(struct kvm *kvm,
 				   struct kvm_irq_ack_notifier *kian);
-void kvm_unregister_irq_ack_notifier(struct kvm *kvm,
-				     struct kvm_irq_ack_notifier *kian);
+void kvm_unregister_irq_ack_notifier(struct kvm_irq_ack_notifier *kian);
 int kvm_request_irq_source_id(struct kvm *kvm);
 void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id);
 

virt/kvm/irq_comm.c

@@ -58,12 +58,16 @@ void kvm_notify_acked_irq(struct kvm *kvm, unsigned gsi)
 void kvm_register_irq_ack_notifier(struct kvm *kvm,
 				   struct kvm_irq_ack_notifier *kian)
 {
+	/* Must be called with in-kernel IRQ chip, otherwise it's nonsense */
+	ASSERT(irqchip_in_kernel(kvm));
+	ASSERT(kian);
 	hlist_add_head(&kian->link, &kvm->arch.irq_ack_notifier_list);
 }
 
-void kvm_unregister_irq_ack_notifier(struct kvm *kvm,
-				     struct kvm_irq_ack_notifier *kian)
+void kvm_unregister_irq_ack_notifier(struct kvm_irq_ack_notifier *kian)
 {
+	if (!kian)
+		return;
 	hlist_del(&kian->link);
 }
 

virt/kvm/kvm_main.c

@@ -143,7 +143,7 @@ static void kvm_free_assigned_device(struct kvm *kvm,
 	if (irqchip_in_kernel(kvm) && assigned_dev->irq_requested)
 		free_irq(assigned_dev->host_irq, (void *)assigned_dev);
 
-	kvm_unregister_irq_ack_notifier(kvm, &assigned_dev->ack_notifier);
+	kvm_unregister_irq_ack_notifier(&assigned_dev->ack_notifier);
 	kvm_free_irq_source_id(kvm, assigned_dev->irq_source_id);
 
 	if (cancel_work_sync(&assigned_dev->interrupt_work))