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Date: Fri, 13 Apr 2007 10:21:17 -0700
From: Jeremy Fitzhardinge <jeremy@goop.org>
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To: Hugh Dickins <hugh@veritas.com>
CC: Andrew Morton <akpm@linux-foundation.org>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH mm] fix i386 get_gate_vma oops
References: <Pine.LNX.4.64.0704131714160.3687@blonde.wat.veritas.com>
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Hugh Dickins wrote:
> Fix oops from i386-make-compat_vdso-runtime-selectable.patch.
>
> Even mingetty at system startup finds it easy to trigger an oops
> while reading /proc/PID/maps: though it has a good hold on the mm
> itself, that cannot stop exit_mm() from resetting tsk->mm to NULL.
>
> (It is usually show_map()'s call to get_gate_vma() which oopses,
> and I expect we could change that to check priv->tail_vma instead;
> but no matter, even m_start()'s call just after get_task_mm() is racy.)
>
> Signed-off-by: Hugh Dickins <hugh@veritas.com>
>   
Hm, OK.

Acked-by: Jeremy Fitzhardinge <jeremy@xensource.com>

    J