[dm-devel] [PATCH 1/6] block: clear the holder releated fields when deleting the kobjects

[Christoph Hellwig]

Zero out the pointers to the holder related kobjects so that the holder
code doesn't incorrectly when called by dm for the delayed holder
registration.

Fixes: 89f871af1b26 ("dm: delay registering the gendisk")
Reported-by: Yu Kuai <yukuai1 at huaweicloud.com>
Signed-off-by: Christoph Hellwig <hch at lst.de>
---
 block/genhd.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/block/genhd.c b/block/genhd.c
index 17b33c62423df..cd90df6c775c2 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -528,8 +528,10 @@ int __must_check device_add_disk(struct device *parent, struct gendisk *disk,
 	blk_unregister_queue(disk);
 out_put_slave_dir:
 	kobject_put(disk->slave_dir);
+	disk->slave_dir = NULL;
 out_put_holder_dir:
 	kobject_put(disk->part0->bd_holder_dir);
+	disk->part0->bd_holder_dir = NULL;
 out_del_integrity:
 	blk_integrity_del(disk);
 out_del_block_link:
@@ -623,7 +625,9 @@ void del_gendisk(struct gendisk *disk)
 	blk_unregister_queue(disk);
 
 	kobject_put(disk->part0->bd_holder_dir);
+	disk->part0->bd_holder_dir = NULL;
 	kobject_put(disk->slave_dir);
+	disk->slave_dir = NULL;
 
 	part_stat_set_all(disk->part0, 0);
 	disk->part0->bd_stamp = 0;
-- 
2.30.2