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Sender: Tejun Heo <htejun@gmail.com>
Date:   Mon, 27 Jun 2022 17:21:12 +0900
From:   Tejun Heo <tj@kernel.org>
To:     Michal Hocko <mhocko@suse.com>
Cc:     Petr Mladek <pmladek@suse.com>,
        Lai Jiangshan <jiangshanlai@gmail.com>,
        linux-kernel@vger.kernel.org,
        Peter Zijlstra <peterz@infradead.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Oleg Nesterov <oleg@redhat.com>,
        "Eric W. Biederman" <ebiederm@xmission.com>
Subject: Re: re. Spurious wakeup on a newly created kthread
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Hello, Michal.

On Mon, Jun 27, 2022 at 10:07:22AM +0200, Michal Hocko wrote:
> So if somebody has woken up our thread from inside kthread() then it
> doesn't have that pointer on the stack and I couldn't it find elsewhere
> either. Maybe somebody has an idea where to look at.

One way could be bpftrace'ing or printking __wake_up_common() and
friends to dump backtrace if it's trying to wake a kthread whose comm
starts with kworker/ and doesn't have (struct worker
*)kthread_data(task)->pool set.

Thanks.

-- 
tejun