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Date: Fri, 24 Feb 2012 11:08:41 -0600 (CST)
From: Christoph Lameter <cl@linux.com>
Subject: Re: [RFC][PATCH] fix move/migrate_pages() race on task struct
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To: Dave Hansen <dave@linux.vnet.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>, linux-kernel@vger.kernel.org, linux-mm@kvack.org

Oh and another thing. There are certain functions that are now called
under rcu read lock()

	security_task_movememory

and

	cpuset_mems_allowed


cpuset_mems_allowed takes a mutex. Hmmm... Under rcu?

security_task_movememory does some kind of security hook.


Is that all safe? If not then we need to take a refcount on the task
struct after all.

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