path: root/block/blk-core.c
diff options
authorJames Bottomley <James.Bottomley@HansenPartnership.com>2009-05-27 14:17:08 +0200
committerJens Axboe <jens.axboe@oracle.com>2009-05-27 14:17:08 +0200
commitba396a6c104682dfe5c8b4fbbf5974d5ac9f3687 (patch)
treeba8bf30382d1891c7f540264b6229db1bc1eb797 /block/blk-core.c
parent3b77f777b8f1c001b63e317c4ce317292ff0ff94 (diff)
block: fix oops with block tag queueing
commit e8939a50466fd963eb1ba9118c34b9ffb7ff6aa6 Author: Tejun Heo <tj@kernel.org> Date: Fri May 8 11:54:16 2009 +0900 block: implement and enforce request peek/start/fetch Added a BUG_ON(blk_queued_rq(req)) to the top of blk_finish_req(). Unfortunately, this checks whether req->queuelist is empty. This list is doing double duty both as the queue list and the tag list, so tagged requests come in here with this not empty and boom (the tag list is emptied by blk_queue_end_tag() lower down). Fix this by moving the BUG_ON to below the end tag we also seem vulnerable to this in blk_requeue_request() as well. I think all uses of blk_queued_rq() need auditing because the check is clearly wrong in the tagged case. Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Diffstat (limited to 'block/blk-core.c')
1 files changed, 4 insertions, 4 deletions
diff --git a/block/blk-core.c b/block/blk-core.c
index 7a4c40184a6..8b3b74e6918 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -956,8 +956,6 @@ EXPORT_SYMBOL(blk_make_request);
void blk_requeue_request(struct request_queue *q, struct request *rq)
- BUG_ON(blk_queued_rq(rq));
trace_block_rq_requeue(q, rq);
@@ -965,6 +963,8 @@ void blk_requeue_request(struct request_queue *q, struct request *rq)
if (blk_rq_tagged(rq))
blk_queue_end_tag(q, rq);
+ BUG_ON(blk_queued_rq(rq));
elv_requeue_request(q, rq);
@@ -2042,11 +2042,11 @@ static bool blk_update_bidi_request(struct request *rq, int error,
static void blk_finish_request(struct request *req, int error)
- BUG_ON(blk_queued_rq(req));
if (blk_rq_tagged(req))
blk_queue_end_tag(req->q, req);
+ BUG_ON(blk_queued_rq(req));
if (unlikely(laptop_mode) && blk_fs_request(req))