block: fix leaking minors of hidden disks

The major/minor of a hidden gendisk is not propagated to the block
device because it is never registered using bdev_add.  But the lack of
bd_dev also causes the dynamic major minor number not to be freed.
Assign bd_dev manually to ensure the dynamic major minor gets freed.

Based on a patch by Keith Busch.

Fixes: 8ddcd65325 ("block: introduce GENHD_FL_HIDDEN")
Reported-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Daniel Wagner <dwagner@suse.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20221010131857.748129-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Christoph Hellwig 2022-10-10 15:18:57 +02:00 committed by Jens Axboe
parent ca5eebda3e
commit a0a6314ae7

View File

@ -507,6 +507,13 @@ int __must_check device_add_disk(struct device *parent, struct gendisk *disk,
*/
dev_set_uevent_suppress(ddev, 0);
disk_uevent(disk, KOBJ_ADD);
} else {
/*
* Even if the block_device for a hidden gendisk is not
* registered, it needs to have a valid bd_dev so that the
* freeing of the dynamic major works.
*/
disk->part0->bd_dev = MKDEV(disk->major, disk->first_minor);
}
disk_update_readahead(disk);