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Date: Wed, 19 Oct 2016 18:12:08 +0200
From: Oleg Nesterov <oleg@redhat.com>
To: Michal Hocko <mhocko@kernel.org>
Cc: Leon Yu <chianglungyu@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Al Viro <viro@zeniv.linux.org.uk>, Kees Cook <keescook@chromium.org>,
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        Janis Danisevskis <jdanis@google.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] proc: fix NULL dereference when reading
        /proc/<pid>/auxv
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On 10/19, Michal Hocko wrote:
>
> Why would we even want to open that file if there is no mm struct?

Agreed this is strange, but I am not sure we can change this old
behaviour. Say, cat /proc/$pid-of-kthread/mem doesn't fail, it shows
the "empty mm".

Oleg.