On Tue, Apr 09, 2013 at 05:04:06PM -0700, H. Peter Anvin wrote:
> On 04/09/2013 05:03 PM, Borislav Petkov wrote:
> > 
> > Note to self: this destroys the src operand but it shouldn't. Fix it
> > tomorrow.
> > 
> 
> I thought movbe was already in qemu just not on by default...?

Yep, this went upstream just last month.

However and AFAICT, this still doesn't help the issue when we run
qemu -enable-kvm and the host doesn't have MOVBE. With my simplistic
thinking, I would expect that kvm would jump to qemu on #UD and let it
emulate the unsupported instruction and go back.

However, as Andre explained it to me, qemu emulation and kvm are
completely unrelated and it is probably very expensive to copy emulation
states to and fro just for a simple instruction. Thus, this simpler
approach to do the emulation straight in kvm as it is done already for a
bunch of other instructions.

-- 
Regards/Gruss,
    Boris.

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