On Wed, Sep 16, 2020 at 04:52:45PM +0200, Danny Milosavljevic wrote:
> commit 692d0626557451c4b557397f20b7394b612d0289
> Author: Christoph Hellwig <hch@lst.de>
> Date:   Tue Sep 1 11:59:41 2020 +0200
> 
>     block: fix locking in bdev_del_partition
>     
>     [ Upstream commit 08fc1ab6d748ab1a690fd483f41e2938984ce353 ]
>     
>     We need to hold the whole device bd_mutex to protect against
>     other thread concurrently deleting out partition before we get
>     to it, and thus causing a use after free.
>     
>     Fixes: cddae808aeb7 ("block: pass a hd_struct to delete_partition")
>     Reported-by: syzbot+6448f3c229bc52b82f69@syzkaller.appspotmail.com
>     Signed-off-by: Christoph Hellwig <hch@lst.de>
>     Signed-off-by: Jens Axboe <axboe@kernel.dk>
>     Signed-off-by: Sasha Levin <sashal@kernel.org>
> 
> ?

Do you think that's the faulty commit? I won't have time to test it
today.