4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jan Kara <jack@xxxxxxx> commit 4b758df21ee7081ab41448d21d60367efaa625b3 upstream. If blkdev_get_by_path() in register_bcache() fails, we try to lookup the block device using lookup_bdev() to detect which situation we are in to properly report error. However we never drop the reference returned to us from lookup_bdev(). Fix that. Signed-off-by: Jan Kara <jack@xxxxxxx> Acked-by: Coly Li <colyli@xxxxxxx> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/md/bcache/super.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -1960,6 +1960,8 @@ static ssize_t register_bcache(struct ko else err = "device busy"; mutex_unlock(&bch_register_lock); + if (!IS_ERR(bdev)) + bdput(bdev); if (attr == &ksysfs_register_quiet) goto out; }