Re: [PATCH] block: don't call blk_mq_run_hw_queues() for dead or dying queues

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 3/26/19 5:07 AM, Hannes Reinecke wrote:
When a queue is dying or dead there is no point in calling
blk_mq_run_hw_queues() in blk_mq_unquiesce_queue(); in fact, doing
so might crash the machine as the queue structures are in the
process of being deleted.

Signed-off-by: Hannes Reinecke <hare@xxxxxxxx>
---
  block/blk-mq.c | 3 ++-
  1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/block/blk-mq.c b/block/blk-mq.c
index a9c181603cbd..b1eeba38bc79 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -258,7 +258,8 @@ void blk_mq_unquiesce_queue(struct request_queue *q)
  	blk_queue_flag_clear(QUEUE_FLAG_QUIESCED, q);
/* dispatch requests which are inserted during quiescing */
-	blk_mq_run_hw_queues(q, true);
+	if (!blk_queue_dying(q) && !blk_queue_dead(q))
+		blk_mq_run_hw_queues(q, true);
  }
  EXPORT_SYMBOL_GPL(blk_mq_unquiesce_queue);

Hi Hannes,

Please provide more context information. In the "dead" state the queue must be run to make sure that all requests that were queued before the "dead" state get processed. The blk_cleanup_queue() function is responsible for stopping all code that can run the queue after all requests have finished and before destruction of the data structures needed for request processing starts.

Bart.



[Index of Archives]     [Linux RAID]     [Linux SCSI]     [Linux ATA RAID]     [IDE]     [Linux Wireless]     [Linux Kernel]     [ATH6KL]     [Linux Bluetooth]     [Linux Netdev]     [Kernel Newbies]     [Security]     [Git]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Device Mapper]

  Powered by Linux