Re: [PATCH 4/6] x86: KVM: Enable AVX-VNNI-INT8 CPUID and expose it to guest

From: Chen, Jiaxi
Date: Thu Oct 20 2022 - 03:14:19 EST




在 2022/10/19 16:52, Borislav Petkov 写道:
> On Wed, Oct 19, 2022 at 04:47:32PM +0800, Jiaxi Chen wrote:
>> AVX-VNNI-INT8 is a new set of instructions in the latest Intel platform
>> Sierra Forest. It multiplies the individual bytes of two unsigned or
>> unsigned source operands, then add and accumulate the results into the
>> destination dword element size operand. This instruction allows for the
>> platform to have superior AI capabilities.
>>
>> The bit definition:
>> CPUID.(EAX=7,ECX=1):EDX[bit 4]
>>
>> This patch enables this CPUID in the kernel feature bits and expose it to
>> guest OS. Since the CPUID involves a bit of EDX (EAX=7,ECX=1) which has not
>> been enumerated yet, this patch adds CPUID_7_1_EDX to CPUID subleaves. At
>> the same time, word 20 is newly-defined in CPU features for CPUID level
>
> For all your commit messages:
>
> Avoid having "This patch" or "This commit" in the commit message. It is
> tautologically useless.

Will follow this in the future. Thanks.
>
> Also, do
>
> $ git grep 'This patch' Documentation/process
>
> for more details.
>
> For this particular one, use scattered.c instead of adding a new leaf.
>
> Thx.
>