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Date: Sat, 24 Mar 2012 20:43:35 +0400
From: Anton Vorontsov <anton.vorontsov@linaro.org>
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
Subject: Re: [PATCH 07/10] um: Should hold tasklist_lock while traversing
 processes
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Cc: Mike Frysinger <vapier@gentoo.org>,
 user-mode-linux-devel@lists.sourceforge.net, linux-sh@vger.kernel.org,
 Richard Weinberger <richard@nod.at>, linuxppc-dev@lists.ozlabs.org,
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 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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On Sat, Mar 24, 2012 at 01:48:23PM +0100, Peter Zijlstra wrote:
> On Sat, 2012-03-24 at 14:30 +0400, Anton Vorontsov wrote:
> > Traversing the tasks requires holding tasklist_lock, otherwise it
> > is unsafe. 
> 
> No it doesn't, it either requires tasklist_lock or rcu_read_lock().

Well, currently the code does neither. :-)

-- 
Anton Vorontsov
Email: cbouatmailru@gmail.com