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Date: Mon, 23 Apr 2012 00:06:41 -0700
From: Anton Vorontsov <anton.vorontsov@linaro.org>
To: Andrew Morton <akpm@linux-foundation.org>, Oleg Nesterov <oleg@redhat.com>
Subject: [PATCH v3 0/9] Fixes for common mistakes w/ for_each_process and
 task->mm
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Cc: linaro-kernel@lists.linaro.org, Mike Frysinger <vapier@gentoo.org>,
 Peter Zijlstra <a.p.zijlstra@chello.nl>,
 user-mode-linux-devel@lists.sourceforge.net, linux-sh@vger.kernel.org,
 Richard Weinberger <richard@nod.at>, patches@linaro.org,
 linux-kernel@vger.kernel.org, uclinux-dist-devel@blackfin.uclinux.org,
 linux-mm@kvack.org, Paul Mundt <lethal@linux-sh.org>,
 John Stultz <john.stultz@linaro.org>,
 KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>,
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Hi all,

This is another resend of several task->mm fixes, the bugs I found
during LMK code audit. Architectures were traverse the tasklist
in an unsafe manner, plus there are a few cases of unsafe access to
task->mm in general.

There were no objections on the previous resend, and the final words
were somewhere along "the patches are fine" line.

In v3:
- Dropped a controversal 'Make find_lock_task_mm() sparse-aware' patch;
- Reword arm and sh commit messages, per Oleg Nesterov's suggestions;
- Added an optimization trick in clear_tasks_mm_cpumask(): take only
  the rcu read lock, no need for the whole tasklist_lock.
  Suggested by Peter Zijlstra.

In v2: 
- introduced a small helper in cpu.c: most arches duplicate the
  same [buggy] code snippet, so it's better to fix it and move the
  logic into a common function.

Thanks,

-- 
Anton Vorontsov
Email: cbouatmailru@gmail.com