On Thu, Aug 19 2021 at 2:05P -0400,
Christoph Hellwig <hch@xxxxxx> wrote:
> Manually reverting "block: remove the extra kobject reference in
> bd_link_disk_holder" as show below fixed the issue for me. I'll spend
> some more time tomorrow trying to fully understan the life time rules
> tomorrow before sending a patch, though.
>
> ---
> From 6b94f5435900d23769db8d07ff47415aab4ac63e Mon Sep 17 00:00:00 2001
> From: Christoph Hellwig <hch@xxxxxx>
> Date: Thu, 19 Aug 2021 20:01:43 +0200
> Subject: Revert "block: remove the extra kobject reference in
> bd_link_disk_holder"
>
> This reverts commit fbd9a39542ecdd2ade55869c13856b2590db3df8.
> ---
> block/holder.c | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/block/holder.c b/block/holder.c
> index 4568cc4f6827..ecbc6941e7d8 100644
> --- a/block/holder.c
> +++ b/block/holder.c
> @@ -106,6 +106,12 @@ int bd_link_disk_holder(struct block_device *bdev, struct gendisk *disk)
> }
>
> list_add(&holder->list, &disk->slave_bdevs);
> + /*
> + * bdev could be deleted beneath us which would implicitly destroy
> + * the holder directory. Hold on to it.
> + */
> + kobject_get(bdev->bd_holder_dir);
> +
> out_unlock:
> mutex_unlock(&disk->open_mutex);
> return ret;
> @@ -138,6 +144,7 @@ void bd_unlink_disk_holder(struct block_device *bdev, struct gendisk *disk)
> if (!WARN_ON_ONCE(holder == NULL) && !--holder->refcnt) {
> if (disk->slave_dir)
> __unlink_disk_holder(bdev, disk);
> + kobject_put(bdev->bd_holder_dir);
> list_del_init(&holder->list);
> kfree(holder);
> }
> --
> 2.30.2
>
OK, this fixed it for me too, thanks.
Mike
