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Date:   Tue, 25 May 2021 09:26:14 +0200
From:   Michal Hocko <mhocko@suse.com>
To:     =?utf-8?B?6ZmI5Yag5pyJ?= <chenguanyou9338@gmail.com>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        linux-kernel@vger.kernel.org, Kees Cook <keescook@chromium.org>,
        lukas.bulwahn@gmail.com, vbabka@suse.cz, gpiccoli@canonical.com,
        chenguanyou <chenguanyou@xiaomi.com>
Subject: Re: [PATCH] hungtask: add filter kthread/check comm
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On Tue 25-05-21 11:27:16, 陈冠有 wrote:
[...]
> These are MTK's LPM designs.

No idea what those are but it seems like an out of tree code.

> If we have linux-api, hungtask can choose to skip kthread, helpful for us
> to debug user space threads in "state=D" when enable hungtask panic.

No, this approach is wrong. You are trying to workaround an incorrect
out of tree code by creating a user visible API. I have already brought
that up in earlier version of this patch.

Nacked-by: Michal Hocko <mhocko@suse.com>

Andrew has already given you a lead on how to fix the said code. Use
TASK_IDLE when waiting for an event. This will both hide that waiting
task from load average accounting and also from the hung task detector.
-- 
Michal Hocko
SUSE Labs