This is a note to let you know that I've just added the patch titled dm rq: check blk_mq_register_dev() return value in dm_mq_init_request_queue() to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: dm-rq-check-blk_mq_register_dev-return-value-in-dm_mq_init_request_queue.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 23a601248958fa4142d49294352fe8d1fdf3e509 Mon Sep 17 00:00:00 2001 From: Bart Van Assche <bart.vanassche@xxxxxxxxxxx> Date: Thu, 27 Apr 2017 10:11:19 -0700 Subject: dm rq: check blk_mq_register_dev() return value in dm_mq_init_request_queue() From: Bart Van Assche <bart.vanassche@xxxxxxxxxxx> commit 23a601248958fa4142d49294352fe8d1fdf3e509 upstream. Otherwise the request-based DM blk-mq request_queue will be put into service without being properly exported via sysfs. Signed-off-by: Bart Van Assche <bart.vanassche@xxxxxxxxxxx> Reviewed-by: Hannes Reinecke <hare@xxxxxxxx> Cc: Christoph Hellwig <hch@xxxxxx> Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/md/dm-rq.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) --- a/drivers/md/dm-rq.c +++ b/drivers/md/dm-rq.c @@ -997,10 +997,14 @@ int dm_mq_init_request_queue(struct mapp dm_init_md_queue(md); /* backfill 'mq' sysfs registration normally done in blk_register_queue */ - blk_mq_register_dev(disk_to_dev(md->disk), q); + err = blk_mq_register_dev(disk_to_dev(md->disk), q); + if (err) + goto out_cleanup_queue; return 0; +out_cleanup_queue: + blk_cleanup_queue(q); out_tag_set: blk_mq_free_tag_set(md->tag_set); out_kfree_tag_set: Patches currently in stable-queue which might be from bart.vanassche@xxxxxxxxxxx are queue-4.9/target-fileio-fix-zero-length-read-and-write-handling.patch queue-4.9/dm-rq-check-blk_mq_register_dev-return-value-in-dm_mq_init_request_queue.patch