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Date:   Fri, 5 May 2023 18:46:00 +0900
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Subject: Re: [syzbot] [fs?] INFO: task hung in synchronize_rcu (4)
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To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Hillf Danton <hdanton@sina.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        syzbot <syzbot+222aa26d0a5dbc2e84fe@syzkaller.appspotmail.com>,
        linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com
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 <20230505083549.GB1770668@hirez.programming.kicks-ass.net>
From:   Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
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On 2023/05/05 17:35, Peter Zijlstra wrote:
>> Linus, I think that "[PATCH v3 (repost)] locking/lockdep: add debug_show_all_lock_holders()"
>> helps here, but I can't wake up locking people. What can we do?
> 
> How is that not also racy ?

Nobody can make this code racy.

> 
> I think I've seen that patch, and it had a some 'blurb' Changelog that
> leaves me wondering wtf the actual problem is and how it attempts to
> solve it and I went on with looking at regressions because more
> important than random weird patch.

Please respond to
https://lkml.kernel.org/393a440f-5f82-432c-bc24-e8de33e29d75@I-love.SAKURA.ne.jp .