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Date:   Sat, 13 May 2023 18:33:16 +0900
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Subject: Re: [PATCH] debugobject: don't wake up kswapd from fill_pool()
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To:     Thomas Gleixner <tglx@linutronix.de>,
        Andrew Morton <akpm@linux-foundation.org>
Cc:     syzbot <syzbot+fe0c72f0ccbb93786380@syzkaller.appspotmail.com>,
        syzkaller-bugs@googlegroups.com, Ingo Molnar <mingo@elte.hu>,
        linux-kernel@vger.kernel.org, linux-mm <linux-mm@kvack.org>,
        Peter Zijlstra <peterz@infradead.org>
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From:   Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
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On 2023/05/13 17:33, Thomas Gleixner wrote:
> Now I just stared at __alloc_pages_slowpath() and looked at the
> condition for wakeup_all_kswapds(). ALLOC_KSWAPD is set because
> debugobject uses GFP_ATOMIC which contains __GFP_KSWAPD_RECLAIM.
> 
> So debug objects needs to have s/GFP_ATOMIC/__GFP_HIGH/ to prevent that
> wakeup path.

Yes. That is exactly what my patch does.