Date:   Mon, 13 Feb 2023 13:05:48 -0500
From:   Alan Stern <stern@rowland.harvard.edu>
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     Peter Zijlstra <peterz@infradead.org>,
        Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>,
        syzkaller <syzkaller@googlegroups.com>,
        Dmitry Vyukov <dvyukov@google.com>,
        "Rafael J. Wysocki" <rafael@kernel.org>,
        Ingo Molnar <mingo@redhat.com>,
        Boqun Feng <boqun.feng@gmail.com>,
        LKML <linux-kernel@vger.kernel.org>,
        USB list <linux-usb@vger.kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Hillf Danton <hdanton@sina.com>
Subject: Re: [PATCH RFC] drivers/core: Replace lockdep_set_novalidate_class()
 with unique class keys
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On Mon, Feb 13, 2023 at 06:51:57PM +0100, Greg Kroah-Hartman wrote:
> But back to the original issue here, why any of this?  What's wrong with
> what we have now?  I haven't seen real locking issues reported yet (only
> odd syzbot reports that didn't make any sense.)  Is this effort even
> worth it?

A large part of the reason those syzbot reports didn't make any sense 
was because they didn't include any lockdep information.  Making lockdep 
aware of device locking would make those reports a lot easier to 
understand and would help with fixing the bugs.  And it might even help 
with catching similar problems before they get merged into the kernel.

Will it be worthwhile in the end?  I have no idea.

Alan Stern