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Message-ID: <1332593303.16159.28.camel@twins>
Subject: Re: [PATCH 07/10] um: Should hold tasklist_lock while traversing
 processes
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Anton Vorontsov <anton.vorontsov@linaro.org>
Cc: Andrew Morton <akpm@linux-foundation.org>, Oleg Nesterov <oleg@redhat.com>,
        Russell King <linux@arm.linux.org.uk>,
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Date: Sat, 24 Mar 2012 13:48:23 +0100
In-Reply-To: <20120324103030.GG29067@lizard>
References: <20120324102609.GA28356@lizard> <20120324103030.GG29067@lizard>
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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().