Re: State Component 18 and Palette 1 (Re: [PATCH 16/19] kvm: x86: Introduce KVM_{G|S}ET_XSAVE2 ioctl)

Nakajima, Jun
2021-12-22T23:51:36Z

> On Dec 22, 2021, at 6:52 AM, Hansen, Dave <dave.hansen@intel.com> wrote:
>
> On 12/20/21 9:54 AM, Nakajima, Jun wrote:
>>> So, I hope that save state 18 will be frozen to 8k. In that case,
>>> and if palette 1 is frozen to the same values as today,
>>> implementing migration will not be a problem; it will be
>>> essentially the same as SSE->AVX (horizontal extension of existing
>>> registers) and/or AVX->AVX512 (both horizontal and vertical
>>> extension).
>>
>> I would like to confirm that the state component 18 will remain 8KB
>> and palette 1 will remain the same.
>
> Is that an architectural statement that will soon be making its way into
> the SDM?

Yes, with the other clarifications (e.g. setting IA32_XFD[18]).

Thanks,
---
Jun