diff --git a/fs/aio.c b/fs/aio.c
index 9f807a5..40517f3 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -978,7 +978,8 @@
 
 	tail = info->tail;
 	event = aio_ring_event(info, tail, KM_IRQ0);
-	tail = (tail + 1) % info->nr;
+	if (++tail >= info->nr)
+		tail = 0;
 
 	event->obj = (u64)(unsigned long)iocb->ki_obj.user;
 	event->data = iocb->ki_user_data;