From mboxrd@z Thu Jan  1 00:00:00 1970
From: Borislav Petkov <bp@alien8.de>
Subject: Re: [RFC PATCH] Emulate MOVBE
Date: Wed, 10 Apr 2013 12:17:21 +0200
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Cc: Andre Przywara <andre@andrep.de>, kvm@vger.kernel.org,
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To: Gleb Natapov <gleb@redhat.com>
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On Wed, Apr 10, 2013 at 01:08:46PM +0300, Gleb Natapov wrote:
> We can add the emulation, but we should not start announcing the
> instruction availability to a guest if host cpu does not have it
> by default. This may trick a guest into thinking that movbe is the
> fastest way to do something when it is not.

That could be a problem because kernels compiled for atom look at CPUID
to check for MOVBE support and refuse to continue if there's none.

-- 
Regards/Gruss,
    Boris.

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