Commit 89ed5fa3 authored by Nilay Shroff's avatar Nilay Shroff Committed by Jens Axboe
Browse files

block: release q->elevator_lock in ioc_qos_write 



The ioc_qos_write method acquires q->elevator_lock to protect
updates to blk-wbt parameters. Once these updates are complete,
the lock should be released before returning from ioc_qos_write.

However, in one code path, the release of q->elevator_lock was
mistakenly omitted, potentially leading to a lock leak. This commit
fixes the issue by ensuring that q->elevator_lock is properly
released in all return paths of ioc_qos_write.

Fixes: 245618f8 ("block: protect wbt_lat_usec using q->elevator_lock")
Reported-by: default avatarkernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202503171650.cc082b66-lkp@intel.com


Signed-off-by: default avatarNilay Shroff <nilay@linux.ibm.com>
Reviewed-by: default avatarMing Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250319105518.468941-2-nilay@linux.ibm.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 989bcd62

block/blk-iocost.c

+1 −0
Original line number Diff line number Diff line
@@ -3348,6 +3348,7 @@ static ssize_t ioc_qos_write(struct kernfs_open_file *of, char *input, 
		wbt_enable_default(disk);



	blk_mq_unquiesce_queue(disk->queue);

	mutex_unlock(&disk->queue->elevator_lock);

	blk_mq_unfreeze_queue(disk->queue, memflags);



	blkg_conf_exit(&ctx);