On 10/6/19 4:45 AM, Ming Lei wrote: > We will stop hw queue and wait for completion of in-flight requests > when one hctx is becoming dead in the following patch. This way may > cause dead-lock for some stacking blk-mq drivers, such as dm-rq and > loop. > > Add blk-mq flag of BLK_MQ_F_NO_MANAGED_IRQ and mark it for dm-rq and > loop, so we needn't to wait for completion of in-flight requests of > dm-rq & loop, then the potential dead-lock can be avoided. > > Cc: Bart Van Assche <bvanassche@xxxxxxx> > Cc: Hannes Reinecke <hare@xxxxxxxx> > Cc: Christoph Hellwig <hch@xxxxxx> > Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> > Cc: Keith Busch <keith.busch@xxxxxxxxx> > Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx> > --- > block/blk-mq-debugfs.c | 1 + > drivers/block/loop.c | 2 +- > drivers/md/dm-rq.c | 2 +- > include/linux/blk-mq.h | 1 + > 4 files changed, 4 insertions(+), 2 deletions(-) > I would have preferred to queue this patch after the next one; introducing a flag which doesn't do anything is a bit odd to me. But anyway: Reviewed-by: Hannes Reinecke <hare@xxxxxxxx> Cheers, Hannes -- Dr. Hannes Reinecke Teamlead Storage & Networking hare@xxxxxxx +49 911 74053 688 SUSE Software Solutions Germany GmbH, Maxfeldstr. 5, 90409 Nürnberg HRB 247165 (AG München), GF: Felix Imendörffer
