From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: Shut up unhandled MSR warnings
Date: Thu, 12 Nov 2015 11:33:33 +0100
Message-ID: <56446AFD.4030800@redhat.com>
References: <20151112101317.GA3649@pd.tnic>
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Cc: =?UTF-8?B?SsO2cmcgUsO2ZGVs?= <joro@8bytes.org>,
	kvm ML <kvm@vger.kernel.org>,
	lkml <linux-kernel@vger.kernel.org>
To: Borislav Petkov <bp@alien8.de>
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On 12/11/2015 11:13, Borislav Petkov wrote:
> Hey Paolo,
> 
> do we apply stuff like that below?

If we really need to, we do.

> When booting guests all the time here, dmesg gets filled up with those
> "unhandled rdmsr" useless warnings. The patch below shuts them up.
> 
> The only problem is that the IC CFG MSR has those fields
> defined starting from F15h and I don't see a way to check the
> family/model/stepping of the guest CPU in kvm. Is there?

Yes, see guest_cpuid_has_* for an example of reading the CPUID values.

But if it's defined for _all_ models starting at family 21, we can just
do it unconditionally.

Paolo