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Date: Tue, 25 Jun 2013 16:25:42 +0530
From: Anshuman Khandual <khandual@linux.vnet.ibm.com>
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To: Michael Ellerman <michael@ellerman.id.au>
Subject: Re: [PATCH 1/8] powerpc/perf: Check that events only include valid
 bits on Power8
References: <1372073336-8189-1-git-send-email-michael@ellerman.id.au>
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Cc: linuxppc-dev@ozlabs.org, sukadev@linux.vnet.ibm.com,
 Paul Mackerras <paulus@samba.org>
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On 06/24/2013 04:58 PM, Michael Ellerman wrote:
> A mistake we have made in the past is that we pull out the fields we
> need from the event code, but don't check that there are no unknown bits
> set. This means that we can't ever assign meaning to those unknown bits
> in future.
> 
> Although we have once again failed to do this at release, it is still
> early days for Power8 so I think we can still slip this in and get away
> with it.
> 
> Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Reviewed-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>