diff --git a/block/blk-core.c b/block/blk-core.c
index 7b63c9b..996ed90 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -1062,6 +1062,9 @@
 
 	elv_completed_request(q, req);
 
+	/* this is a bio leak */
+	WARN_ON(req->bio != NULL);
+
 	/*
 	 * Request may not have originated from ll_rw_blk. if not,
 	 * it didn't come out of our reserved rq pools