Re: [syzbot] [kernfs?] possible deadlock in __kernfs_remove

From: Tetsuo Handa
Date: Mon Jun 24 2024 - 19:27:56 EST


This dependency is added by recent bug fix commit c0a40097f0bc ("drivers:
core: synchronize really_probe() and dev_uevent()").

Commit 4a0079bc7aae ("nvdimm: Replace lockdep_mutex with local lock
classes") changed to assign nvdimm_namespace_key on dev->mutex instead of
__lockdep_no_validate__, which made lockdep to report this dependency.

On 2024/06/25 5:40, syzbot wrote:
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit: 626737a5791b Merge tag 'pinctrl-v6.10-2' of git://git.kern..
> git tree: upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=143a383e980000
> kernel config: https://syzkaller.appspot.com/x/.config?x=d6b9ee98d841760c
> dashboard link: https://syzkaller.appspot.com/bug?extid=4762dd74e32532cda5ff
> compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40