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Date: Wed, 18 May 2011 15:00:04 +0200
From: Oleg Nesterov <oleg@redhat.com>
To: Jiri Slaby <jslaby@suse.cz>
Cc: akpm@linux-foundation.org, linux-mm@kvack.org,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        jirislaby@gmail.com, Alan Cox <alan@lxorguk.ukuu.org.uk>,
        Al Viro <viro@zeniv.linux.org.uk>, Andi Kleen <andi@firstfloor.org>
Subject: Re: [PATCH v2 1/3] coredump: use get_task_comm for %e filename
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Message-ID: <20110518130004.GA10638@redhat.com>
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Sorry for delay,

On 05/12, Jiri Slaby wrote:
>
> We currently access current->comm directly. As we have
> prctl(PR_SET_NAME), we need the access be protected by task_lock. This
> is exactly what get_task_comm does, so use it.
>
> I'm not 100% convinced prctl(PR_SET_NAME) may be called at the time of
> core dump,

It can't be called. Apart from current, a sub-thread can change ->comm[]
via /proc/pid/comm, but we already killed all threads.

> but the locking won't hurt.

Agreed, the patch looks correct. but still unneeded.

Oleg.