block: call blk_exit_queue() before freeing q->stats
authorMing Lei <ming.lei@redhat.com>
Tue, 21 Dec 2021 04:04:36 +0000 (12:04 +0800)
committerJens Axboe <axboe@kernel.dk>
Tue, 21 Dec 2021 04:07:51 +0000 (21:07 -0700)
blk_stat_disable_accounting() is added in commit 68497092bde9
("block: make queue stat accounting a reference"), and called in
kyber_exit_sched().

So we have to free q->stats after elevator is unloaded from
blk_exit_queue() in blk_release_queue(). Otherwise kernel panic
is caused.

Fixes: 68497092bde9 ("block: make queue stat accounting a reference")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20211221040436.1333880-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
block/blk-sysfs.c

index 3e63573..e20eadf 100644 (file)
@@ -791,11 +791,11 @@ static void blk_release_queue(struct kobject *kobj)
                blk_stat_remove_callback(q, q->poll_cb);
        blk_stat_free_callback(q->poll_cb);
 
+       blk_exit_queue(q);
+
        blk_free_queue_stats(q->stats);
        kfree(q->poll_stat);
 
-       blk_exit_queue(q);
-
        blk_queue_free_zone_bitmaps(q);
 
        if (queue_is_mq(q))