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| author | Mike Snitzer <snitzer@redhat.com> | 2015-05-28 21:12:52 +0200 |
|---|---|---|
| committer | Mike Snitzer <snitzer@redhat.com> | 2015-05-29 17:07:36 +0200 |
| commit | e5d8de32cc02a259e1a237ab57cba00f2930fa6a (patch) | |
| tree | 5c0230f71e12c9349e9c755f722bf837456b0802 /drivers/md/dm.c | |
| parent | dm: requeue from blk-mq dm_mq_queue_rq() using BLK_MQ_RQ_QUEUE_BUSY (diff) | |
| download | linux-e5d8de32cc02a259e1a237ab57cba00f2930fa6a.tar.xz linux-e5d8de32cc02a259e1a237ab57cba00f2930fa6a.zip | |
dm: fix false warning in free_rq_clone() for unmapped requests
When stacking request-based dm device on non blk-mq device and
device-mapper target could not map the request (error target is used,
multipath target with all paths down, etc), the WARN_ON_ONCE() in
free_rq_clone() will trigger when it shouldn't.
The warning was added by commit aa6df8d ("dm: fix free_rq_clone() NULL
pointer when requeueing unmapped request"). But free_rq_clone() with
clone->q == NULL is valid usage for the case where
dm_kill_unmapped_request() initiates request cleanup.
Fix this false warning by just removing the WARN_ON -- it only generated
false positives and was never useful in catching the intended case
(completing clone request not being mapped e.g. clone->q being NULL).
Fixes: aa6df8d ("dm: fix free_rq_clone() NULL pointer when requeueing unmapped request")
Reported-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reported-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Diffstat (limited to 'drivers/md/dm.c')
| -rw-r--r-- | drivers/md/dm.c | 8 |
1 files changed, 3 insertions, 5 deletions
diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 1badfb250a18..e24069aaeb18 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1082,13 +1082,11 @@ static void rq_completed(struct mapped_device *md, int rw, bool run_queue) dm_put(md); } -static void free_rq_clone(struct request *clone, bool must_be_mapped) +static void free_rq_clone(struct request *clone) { struct dm_rq_target_io *tio = clone->end_io_data; struct mapped_device *md = tio->md; - WARN_ON_ONCE(must_be_mapped && !clone->q); - blk_rq_unprep_clone(clone); if (md->type == DM_TYPE_MQ_REQUEST_BASED) @@ -1132,7 +1130,7 @@ static void dm_end_request(struct request *clone, int error) rq->sense_len = clone->sense_len; } - free_rq_clone(clone, true); + free_rq_clone(clone); if (!rq->q->mq_ops) blk_end_request_all(rq, error); else @@ -1151,7 +1149,7 @@ static void dm_unprep_request(struct request *rq) } if (clone) - free_rq_clone(clone, false); + free_rq_clone(clone); } /* |