Re: [PATCH 4/6] x86/cpu: Add platform ID to CPU info structure

[Sohil Mehta]

On 2/6/2026 3:14 PM, Dave Hansen wrote:
> 
> From: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
> 
> The end goal here is to be able to do x86_match_cpu() and match on a
> specific platform ID. While it would be possible to stash this ID
> off somewhere or read it dynamically, that approaches would not be
> consistent with the other fields which can be matched.
> 
> Read the platform ID and store it in cpuinfo_x86->x86_platform_id.
> 
> There are lots of sites to set this new field. Place it near
> the place c->microcode is established since the platform ID is
> so closely intertwined with microcode updates.
> 
> Note: This should not grow the size of 'struct cpuinfo_x86' in
> practice since the u8 fits next to another u8 in the structure.
> 
> Signed-off-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>

Reviewed-by: Sohil Mehta <sohil.mehta@xxxxxxxxx>