diff options
| author | Bart Van Assche <bart.vanassche@sandisk.com> | 2016-11-11 17:05:27 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-01-06 10:40:15 +0100 |
| commit | e362c317ba76c9d397238737deef952187a21395 (patch) | |
| tree | 034b5468ac04b334b1a040cf8069e28e6503b6a3 /drivers | |
| parent | 2c017f77e13d4325d8739fc9ed7ed2c3629da845 (diff) | |
dm rq: fix a race condition in rq_completed()
commit d15bb3a6467e102e60d954aadda5fb19ce6fd8ec upstream.
It is required to hold the queue lock when calling blk_run_queue_async()
to avoid that a race between blk_run_queue_async() and
blk_cleanup_queue() is triggered.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/md/dm-rq.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/drivers/md/dm-rq.c b/drivers/md/dm-rq.c index 1d0d2adc050a..31a89c8832c0 100644 --- a/drivers/md/dm-rq.c +++ b/drivers/md/dm-rq.c @@ -226,6 +226,9 @@ static void rq_end_stats(struct mapped_device *md, struct request *orig) */ static void rq_completed(struct mapped_device *md, int rw, bool run_queue) { + struct request_queue *q = md->queue; + unsigned long flags; + atomic_dec(&md->pending[rw]); /* nudge anyone waiting on suspend queue */ @@ -238,8 +241,11 @@ static void rq_completed(struct mapped_device *md, int rw, bool run_queue) * back into ->request_fn() could deadlock attempting to grab the * queue lock again. */ - if (!md->queue->mq_ops && run_queue) - blk_run_queue_async(md->queue); + if (!q->mq_ops && run_queue) { + spin_lock_irqsave(q->queue_lock, flags); + blk_run_queue_async(q); + spin_unlock_irqrestore(q->queue_lock, flags); + } /* * dm_put() must be at the end of this function. See the comment above |