From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Yan, Zheng" <zheng.z.yan@linux.intel.com>
Subject: Re: perf uncore & lkvm woes
Date: Thu, 16 Aug 2012 15:38:16 +0800
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Cc: Pekka Enberg <penberg@kernel.org>,
	Sasha Levin <levinsasha928@gmail.com>,
	Asias He <asias.hejun@gmail.com>,
	Cyrill Gorcunov <gorcunov@gmail.com>,
	Ingo Molnar <mingo@elte.hu>, KVM General <kvm@vger.kernel.org>
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
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On 08/16/2012 03:19 PM, Peter Zijlstra wrote:
> On Thu, 2012-08-16 at 10:01 +0300, Pekka Enberg wrote:
>> Has anyone seen this? It's kvmtool/next with 3.6.0-rc1. Looks like we
>> are doing uncore_init() on virtualized CPU which breaks boot. 
> 
> I think you're the first.. I don't normally use kvm if I can at all
> avoid it.
> 
> But I think its a 'simple' matter of kvm not emulating the entire
> hardware. Afaik the uncore isn't enumerated and we simply assume MSR
> presence based on cpu model.

The Intel uncore doc does not specify how to check if uncore exist.
How about disabling uncore on virtualized CPU?

Regards
Yan, Zheng