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Subject: Re: [PATCH 2/3] perf_events: fix validation of events using an
 extra reg (v2)
From: Peter Zijlstra <peterz@infradead.org>
To: Stephane Eranian <eranian@google.com>
Cc: linux-kernel@vger.kernel.org, mingo@elte.hu, andi@firstfloor.org,
        ming.m.lin@intel.com
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	 <BANLkTimZhpfgKoEki16r5zabNCrvK-GsUw@mail.gmail.com>
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Date: Mon, 23 May 2011 09:47:58 +0200
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On Fri, 2011-05-20 at 18:45 +0200, Stephane Eranian wrote:
> On Fri, May 20, 2011 at 5:05 PM, Peter Zijlstra <peterz@infradead.org> wrote:
> > On Fri, 2011-05-20 at 16:37 +0200, Stephane Eranian wrote:
> >> The is_fake field is necessary to avoid a lockdep issue having
> >> to do with interrupt masking and era->lock.
> >
> > Why not simply disable IRQs in both validate_* functions?
> >
> Could do that too if you think that's cleaner.

Its saner than making that code path conditional, but an alternative
solution is to give the fake thing a different lock class.