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Date: Fri, 29 Nov 2013 21:31:03 +0100
From: Borislav Petkov <bp@alien8.de>
To: Stephane Eranian <eranian@google.com>
Cc: Vince Weaver <vince@deater.net>, Ingo Molnar <mingo@kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Peter Zijlstra <peterz@infradead.org>, "mingo@elte.hu" <mingo@elte.hu>,
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        Arnaldo Carvalho de Melo <acme@redhat.com>,
        Jiri Olsa <jolsa@redhat.com>, "Yan, Zheng" <zheng.z.yan@intel.com>,
        Maria Dimakopoulou <maria.n.dimakopoulou@gmail.com>
Subject: Re: [PATCH v7 3/4] perf,x86: add Intel RAPL PMU support
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On Fri, Nov 29, 2013 at 09:09:46PM +0100, Stephane Eranian wrote:
> > So in theory it would be harmless to export the values even if not
> > supported.  What is the worst failure mode?  That somehow a recent CPU
> > doesn't support the MSR and we get a GPF when trying to access it?
> >
> Yes. I think that's what you get with DRAM on client for instance.

We have rdmsr_safe for non-existent MSRs, in case touching such is the
issue.

-- 
Regards/Gruss,
    Boris.

Sent from a fat crate under my desk. Formatting is fine.
--