From a3996d11f3ab743e6cc4e3529ce9459c2cd27139 Mon Sep 17 00:00:00 2001 From: Nilay Shroff Date: Thu, 13 Mar 2025 17:21:50 +0530 Subject: block: protect debugfs attrs using elevator_lock instead of sysfs_lock Currently, the block debugfs attributes (tags, tags_bitmap, sched_tags, and sched_tags_bitmap) are protected using q->sysfs_lock. However, these attributes are updated in multiple scenarios: - During driver probe method - During an elevator switch/update - During an nr_hw_queues update - When writing to the sysfs attribute nr_requests All these update paths (except driver probe method, which doesn't require any protection) are already protected using q->elevator_lock. To ensure consistency and proper synchronization, replace q->sysfs_lock with q->elevator_lock for protecting these debugfs attributes. Signed-off-by: Nilay Shroff Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/20250313115235.3707600-2-nilay@linux.ibm.com [axboe: some commit message rewording/fixes] Signed-off-by: Jens Axboe --- include/linux/blkdev.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'include/linux/blkdev.h') diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index dcf8fce15e23..8d072042790e 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -566,9 +566,9 @@ struct request_queue { * nr_requests and wbt latency, this lock also protects the sysfs attrs * nr_requests and wbt_lat_usec. Additionally the nr_hw_queues update * may modify hctx tags, reserved-tags and cpumask, so this lock also - * helps protect the hctx attrs. To ensure proper locking order during - * an elevator or nr_hw_queue update, first freeze the queue, then - * acquire ->elevator_lock. + * helps protect the hctx sysfs/debugfs attrs. To ensure proper locking + * order during an elevator or nr_hw_queue update, first freeze the + * queue, then acquire ->elevator_lock. */ struct mutex elevator_lock; -- cgit v1.2.3