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Message-ID: <fd2f89d9-73a5-c155-48a5-ccc6e93310b2@I-love.SAKURA.ne.jp>
Date:   Fri, 5 May 2023 18:49:39 +0900
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Subject: Re: [syzbot] [fs?] INFO: task hung in synchronize_rcu (4)
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From:   Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
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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On 2023/05/05 18:46, Tetsuo Handa wrote:
> 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.

Oops, nobody can make this code race-free.

Capturing vmcore is not an option.

> 
>>
>> 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 .
> 

I am waiting for your response.
But since you don't respond, I have to repeat re-posting.