[PATCH 07/37] iommu: Add a page fault handler

Hi Jonathan,

Thanks for reviewing

On 08/03/18 15:40, Jonathan Cameron wrote:

quoted

+/**
+ * iommu_fault_queue_unregister() - Unregister an IOMMU driver from the fault
+ * queue.
+ * @flush_notifier: same parameter as iommu_fault_queue_register
+ */
+void iommu_fault_queue_unregister(struct notifier_block *flush_notifier)
+{
+	down_write(&iommu_fault_queue_sem);
+	if (refcount_dec_and_test(&iommu_fault_queue_refs)) {
+		destroy_workqueue(iommu_fault_queue);
+		iommu_fault_queue = NULL;
+	}
+	up_write(&iommu_fault_queue_sem);
+
+	if (flush_notifier)
+		blocking_notifier_chain_unregister(&iommu_fault_queue_flush_notifiers,
+						   flush_notifier);

I would expect the ordering in queue_unregister to be the reverse of queue
register (to make it obvious there are no races).

That would put this last block at the start before potentially destroying
the work queue.  If I'm missing something then perhaps a comment to
explain why the ordering is not the obvious one?

Sure, I'll fix the order, I don't think there was any good reason for it

Thanks,
Jean