Re: [Qemu-devel] [PATCH build-fix] target-i386: emulate CPUID level of real hardware

[Eduardo Habkost]

On Thu, Jul 09, 2015 at 09:07:39PM +0200, Radim Krčmář wrote:
> W10 insider has a bug where it ignores CPUID level and interprets
> CPUID.(EAX=07H, ECX=0H) incorrectly, because CPUID in fact returned
> CPUID.(EAX=04H, ECX=0H);  this resulted in execution of unsupported
> instructions.
> 
> While it's a Windows bug, there is no reason to emulate incorrect level.
> 
> I used http://instlatx64.atw.hu/ as a source of CPUID and checked that
> it matches Penryn Xeon X5472, Westmere Xeon W3520, SandyBridge i5-2540M,
> and Haswell i5-4670T.
> 
> kvm64 and qemu64 were bumped to 0xD to allow all available features for
> them (and to avoid the same Windows bug).
> 
> Signed-off-by: Radim Krčmář <address@hidden>
> Reviewed-by: Eduardo Habkost <address@hidden>
> Signed-off-by: Eduardo Habkost <address@hidden>

Thanks, applied to x86 tree. As the existing code prevents a guest OS
from running, I consider it a bug fix.

-- 
Eduardo