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Subject: Re: [tip:core/ipi] generic-ipi: eliminate spurious
 pointlessWARN_ON()s
From: Peter Zijlstra <peterz@infradead.org>
To: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Ingo Molnar <mingo@elte.hu>, Jan Beulich <jbeulich@novell.com>,
       tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com,
       linux-kernel@vger.kernel.org
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Date: Sat, 21 Mar 2009 11:20:06 +0100
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On Fri, 2009-03-20 at 16:40 -0700, Eric W. Biederman wrote:
> It doesn't look like read==2 works properly because it does not log any
> locks grabbed underneath the reader lock.  Is that deliberate?  It certainly
> does not seem to be correct.

You're right, it doesn't work correctly. One of the patches in that heap
I pointed you at tries to fix it, but gets it wrong.