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Date:   Tue, 1 Dec 2020 13:35:56 +0100
From:   Oleg Nesterov <oleg@redhat.com>
To:     "Eric W. Biederman" <ebiederm@xmission.com>
Cc:     Wen Yang <wenyang@linux.alibaba.com>,
        Alexey Dobriyan <adobriyan@gmail.com>,
        Christian Brauner <christian@brauner.io>,
        linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH] proc: add locking checks in proc_inode_is_dead
Message-ID: <20201201123556.GB2700@redhat.com>
References: <20201128175850.19484-1-wenyang@linux.alibaba.com>
 <87zh2yit5u.fsf@x220.int.ebiederm.org>
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On 11/30, Eric W. Biederman wrote:
>
> Ouch!!!!  Oleg I just looked the introduction of proc_inode_is_dead in
> d855a4b79f49 ("proc: don't (ab)use ->group_leader in proc_task_readdir()
> paths") introduced a ``regression''.
>
> Breaking the logic introduced in 7d8952440f40 ("[PATCH] procfs: Fix
> listing of /proc/NOT_A_TGID/task") to keep those directory listings not
> showing up.

Sorry, I don't understand...

Do you mean that "ls /proc/pid/task" can see an empty dir? Afaics this
was possible before d855a4b79f49 too.

Or what?

Oleg.