Re: [PATCH] x86: kvm: Restrict X86_FEATURE_VMMCALL to x86_64 platform

[Paolo Bonzini]

On 31/07/2018 14:57, tedheadster wrote:
>>
>> This shouldn't be necessary; for systems that don't have virtualization
>> extensions, the comment explains why setting X86_FEATURE_VMMCALL is safe.
>>
>> But it is also wrong, because you can run a 32-bit kernel as a guest on
>> a 64-bit processor, and then it should set X86_FEATURE_VMMCALL because
>> the processor has the vmmcall instruction and not Intel's vmcall.
>>
> 
> Paolo,
>   I'm running this on a bare metal machine (no virtualization) with a
> 32-bit AMD i486 class cpu. Should the feature be showing up in
> /proc/cpuinfo under the 'flags' line? It does on my machine, and it
> looked wrong to me.

It's a bit silly, but it's not particularly wrong.

Paolo