From 77482c4dd4a014268a1bdcf05ff20f8cbb6d5500 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 15 Nov 2022 22:10:45 +0800 Subject: [PATCH] block: clear ->slave_dir when dropping the main slave_dir reference [ Upstream commit d90db3b1c8676bc88b4309c5a571333de2263b8e ] Zero out the pointer to ->slave_dir so that the holder code doesn't incorrectly treat the object as alive when add_disk failed or after del_gendisk was called. Fixes: 89f871af1b26 ("dm: delay registering the gendisk") Reported-by: Yu Kuai Signed-off-by: Christoph Hellwig Signed-off-by: Yu Kuai Reviewed-by: Mike Snitzer Link: https://lore.kernel.org/r/20221115141054.1051801-2-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- block/genhd.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/block/genhd.c b/block/genhd.c index 68065189ca17..a1d9e785dcf7 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -530,6 +530,7 @@ out_unregister_queue: rq_qos_exit(disk->queue); out_put_slave_dir: kobject_put(disk->slave_dir); + disk->slave_dir = NULL; out_put_holder_dir: kobject_put(disk->part0->bd_holder_dir); out_del_integrity: @@ -624,6 +625,7 @@ void del_gendisk(struct gendisk *disk) kobject_put(disk->part0->bd_holder_dir); kobject_put(disk->slave_dir); + disk->slave_dir = NULL; part_stat_set_all(disk->part0, 0); disk->part0->bd_stamp = 0;