From: Ming Lei ming.lei@redhat.com
commit daaca3522a8e67c46e39ef09c1d542e866f85f3b upstream.
blkcg_init_queue() may add rq qos structures to request queue, previously blk_cleanup_queue() calls rq_qos_exit() to release them, but commit 8e141f9eb803 ("block: drain file system I/O on del_gendisk") moves rq_qos_exit() into del_gendisk(), so memory leak is caused because queues may not have disk, such as un-present scsi luns, nvme admin queue, ...
Fixes the issue by adding rq_qos_exit() to blk_cleanup_queue() back.
BTW, v5.18 won't need this patch any more since we move blkcg_init_queue()/blkcg_exit_queue() into disk allocation/release handler, and patches have been in for-5.18/block.
Cc: Christoph Hellwig hch@lst.de Cc: stable@vger.kernel.org Fixes: 8e141f9eb803 ("block: drain file system I/O on del_gendisk") Reported-by: syzbot+b42749a851a47a0f581b@syzkaller.appspotmail.com Signed-off-by: Ming Lei ming.lei@redhat.com Reviewed-by: Bart Van Assche bvanassche@acm.org Reviewed-by: Christoph Hellwig hch@lst.de Link: https://lore.kernel.org/r/20220314043018.177141-1-ming.lei@redhat.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- block/blk-core.c | 4 ++++ 1 file changed, 4 insertions(+)
--- a/block/blk-core.c +++ b/block/blk-core.c @@ -49,6 +49,7 @@ #include "blk-mq.h" #include "blk-mq-sched.h" #include "blk-pm.h" +#include "blk-rq-qos.h"
struct dentry *blk_debugfs_root;
@@ -380,6 +381,9 @@ void blk_cleanup_queue(struct request_qu */ blk_freeze_queue(q);
+ /* cleanup rq qos structures for queue without disk */ + rq_qos_exit(q); + blk_queue_flag_set(QUEUE_FLAG_DEAD, q);
blk_sync_queue(q);