Re: [PATCH 01/13] x86/CPU/AMD: Add ZenX generations flags

[Tom Lendacky]

On 11/30/23 11:13, Borislav Petkov wrote:
> On Thu, Nov 30, 2023 at 11:05:14AM -0600, Tom Lendacky wrote:
> > Previously just being family 17h or 19h would get X86_FEATURE_ZEN set. With
> > this, if the model check doesn't match, you won't get any X86_FEATURE_ZEN*
> > set. Should you do set X86_FEATURE_ZEN here, e.g. lowest common denominator
> > for the family?
>
> My assumption/expectation is that those WARNs should never happen
> because they will be caught early enough in enablement and I will get
> patches.
>
> Besides, X86_FEATURE_ZEN means only Zen1 now.

There are references to X86_FEATURE_ZEN in arch/x86/kernel/process.c and 
drivers/acpi/resource.c that should probably be vetted.

Maybe having X86_FEATURE_ZEN mean all ZEN (and set for anything family 17h 
or higher) and a separate per generation, e.g. X86_FEATURE_ZEN1, when you 
need to be specific, would work.

Thanks,
Tom

>