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Date: Mon, 20 Sep 2010 10:41:39 +0200
From: Robert Richter <robert.richter@amd.com>
To: Stephane Eranian <eranian@google.com>
CC: Ingo Molnar <mingo@elte.hu>, Peter Zijlstra <peterz@infradead.org>,
        Don Zickus <dzickus@redhat.com>,
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        "yinghai@kernel.org" <yinghai@kernel.org>,
        "andi@firstfloor.org" <andi@firstfloor.org>
Subject: Re: [PATCH] perf, x86: catch spurious interrupts after disabling
 counters
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On 17.09.10 09:06:09, Stephane Eranian wrote:
> Robert.
> 
> Does it mean that with this patch, we don't need Don's back-to-back NMI patch
> anymore?

No, both fix separate things.

Don's patch is about this problem on Intel systems, where ack'ing the
status late may cause empty nmis:

 http://lkml.org/lkml/2010/8/25/124

My patch fixes a problem that after disabling a counter, it could
still cause a late NMI. It was observed on AMD systems, but may also
be valid for Intel systems.

-Robert

-- 
Advanced Micro Devices, Inc.
Operating System Research Center