Re: [PATCH -v2] kvm: Emulate MOVBE

[Borislav Petkov <bp@alien8.de>]

On Thu, Apr 11, 2013 at 05:28:18PM +0300, Gleb Natapov wrote:
> On Thu, Apr 11, 2013 at 02:18:15AM +0200, Borislav Petkov wrote:
> > On Wed, Apr 10, 2013 at 03:16:39PM +0300, Gleb Natapov wrote:
> > > Right, the question is how kernel can tell QEMU that the cpuid bit is
> > > supported but should not be set unless explicitly asked by an user.
> > 
> > Actually, this seems to work with the patch below based on whether you
> > have "+movbe" in the -cpu option or not.
> > 
> The problem is that -cpu host will have it unconditionally and this is
> definitely not what we want.

Hmm, ok, I see what you mean. -cpu host boots the atom kernel just fine.

Well, with my limited qemu exposure, I'd guess
cpu_x86_parse_featurestr() would need to somehow say to
x86_cpu_realizefn that it has parsed a "+movbe" on the command line and
the latter has to keep that bit enabled when doing the checks against
kvm in kvm_check_features_against_host and filter_features_for_kvm().

Unless you have a better idea, that is.

Thanks.

-- 
Regards/Gruss,
    Boris.

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