[PATCH v2 3/3] block: fix leak of q->rq_wb
From: Omar Sandoval <osandov@osandov.com>
Date: 2017-03-28 23:13:17
Subsystem:
block layer, the rest · Maintainers:
Jens Axboe, Linus Torvalds
From: Omar Sandoval <redacted>
CONFIG_DEBUG_TEST_DRIVER_REMOVE found a possible leak of q->rq_wb when a
request queue is reregistered. This has been a problem since wbt was
introduced, but the WARN_ON(!list_empty(&stats->callbacks)) in the
blk-stat rework exposed it. Fix it by cleaning up wbt when we unregister
the queue.
Fixes: 87760e5eef35 ("block: hook up writeback throttling")
Signed-off-by: Omar Sandoval <redacted>
---
block/blk-sysfs.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index 833fb7f9ce9d..45854266e398 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c@@ -795,7 +795,6 @@ static void blk_release_queue(struct kobject *kobj) struct request_queue *q = container_of(kobj, struct request_queue, kobj); - wbt_exit(q); if (test_bit(QUEUE_FLAG_POLL_STATS, &q->queue_flags)) blk_stat_remove_callback(q, q->poll_cb); blk_stat_free_callback(q->poll_cb);
@@ -938,6 +937,9 @@ void blk_unregister_queue(struct gendisk *disk) queue_flag_clear_unlocked(QUEUE_FLAG_REGISTERED, q); + wbt_exit(q); + + if (q->mq_ops) blk_mq_unregister_dev(disk_to_dev(disk), q);
--
2.12.1