[PATCH 2/9] dm: Fix a race condition related to stopping and starting queues

[Johannes Thumshirn]

On Mon, Sep 26, 2016 at 11:26:50AM -0700, 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 <bart.vanassche at sandisk.com>
> Cc: Mike Snitzer <snitzer at redhat.com>
> ---

Looks good,
Reviewed-by: Johannes Thumshirn <jthumshirn at suse.de>

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Johannes Thumshirn                                          Storage
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