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Date: Sat, 20 Sep 2014 20:57:05 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Kirill Tkhai <tkhai@yandex.ru>
Cc: linux-kernel@vger.kernel.org, Ingo Molnar <mingo@redhat.com>,
        Kirill Tkhai <ktkhai@parallels.com>
Subject: Re: [PATCH 3/7] sched: Use dl_bw_of() under RCU read lock
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On Sat, Sep 20, 2014 at 08:51:28PM +0400, Kirill Tkhai wrote:
> From: Kirill Tkhai <ktkhai@parallels.com>
> 
> dl_bw_of() dereferences rq->rd which has to have RCU read lock held.
> Probability of use-after-free and memory corruption aren't zero here.
> 

Additionally we might want to add something like:
lockdep_assert_held_rcu() and put that in dl_bw_of() and other such
places.