From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Zijlstra <peterz@infradead.org>
Subject: Re: linux 3.13 guest crash with -cpu host
Date: Mon, 3 Feb 2014 15:12:35 +0100
Message-ID: <20140203141235.GJ8874@twins.programming.kicks-ass.net>
References: <20140202205930.GA2157@redhat.com>
 <20140203125828.GH2221@otherpad.lan.raisama.net>
 <20140203140601.GA24944@redhat.com>
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Cc: Eduardo Habkost <ehabkost@redhat.com>, kvm@vger.kernel.org,
	pbonzini@redhat.com
To: "Michael S. Tsirkin" <mst@redhat.com>
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On Mon, Feb 03, 2014 at 04:06:01PM +0200, Michael S. Tsirkin wrote:
> On Mon, Feb 03, 2014 at 10:58:28AM -0200, Eduardo Habkost wrote:

> > Where does the "v2 and above have a perf capabilities MSR" claim in the code
> > come from?
> 
> 
> But why doesn't it crash on baremetal?
> Probably baremetal simply returns 0 or something.
> Let me try ..

The claim "v2 and above have FEATURE_PDCM" is in fact true for real
hardware.

If it didn't the rdmsr() would have generated an exception and we'd have
crashed just like your virtual thingy did.