+struct task_struct *fault_handler;
+
+void vas_wakeup_fault_handler(int virq, void *arg)
+{
+	struct vas_instance *vinst = arg;
+
+	atomic_inc(&vinst->pending_fault);
+	wake_up(&vinst->fault_wq);
+}
+
+/*
+ * Fault handler thread for each VAS instance and process fault CRBs.
+ */
+static int fault_handler_func(void *arg)
+{
+	struct vas_instance *vinst = (struct vas_instance *)arg;
+
+	do {
+		if (signal_pending(current))
+			flush_signals(current);
+
+		wait_event_interruptible(vinst->fault_wq,
+					atomic_read(&vinst->pending_fault) ||
+					kthread_should_stop());
+
+		if (kthread_should_stop())
+			break;
+
+		atomic_dec(&vinst->pending_fault);
+	} while (!kthread_should_stop());
+
+	return 0;
+}

Pleae use threaded interrupts instead of reinventing them badly.