On 09/26/2016 08:26 PM, Bart Van Assche wrote:

Ensure that all ongoing dm_mq_queue_rq() and dm_mq_requeue_request()
calls have stopped before setting the "queue stopped" flag. This
allows to remove the "queue stopped" test from dm_mq_queue_rq() and
dm_mq_requeue_request(). This patch fixes a race condition because
dm_mq_queue_rq() is called without holding the queue lock and hence
BLK_MQ_S_STOPPED can be set at any time while dm_mq_queue_rq() is
in progress.

Signed-off-by: Bart Van Assche <redacted>
Cc: Mike Snitzer <redacted>
---
 drivers/md/dm-rq.c | 14 +++-----------
 1 file changed, 3 insertions(+), 11 deletions(-)

Reviewed-by: Hannes Reinecke <hare@suse.com>

Cheers,

Hannes
-- 
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