Re: [PATCH V2 0/8] x86/topology: Improve CPUID.1F handling

From: Zhang Rui
Date: Mon Sep 19 2022 - 21:57:27 EST


On Tue, 2022-08-16 at 13:16 +0800, Zhang Rui wrote:
> On Intel AlderLake-N platforms where there are Ecores only, the Ecore
> Module topology is enumerated via CPUID.1F Module level, which has
> not
> been supported by Linux kernel yet.
>
> This exposes two issues in current CPUID.1F handling code.
> 1. Linux interprets the Module ID bits as package ID and erroneously
> reports a multi module system as a multi-package system.
> 2. Linux excludes the unknown Module ID bits from the core ID, and
> results
> in duplicate core ID’s shown in a package after the first issue
> solved.
>
> Plus that, a third problem is observed on Intel Hybrid ADL-S/P
> platforms.
> The return value of CPUID.1F SMT level EBX (number of siblings)
> differs on
> Pcore CPUs and Ecore CPUs, and results in inconsistent
> smp_num_siblings
> value based on the Pcore/Ecore CPU enumeration order. This could
> bring
> some potential issues although we have not observed any
> functionalities
> issues so far.
>
> This patch series fixes these three problems in CPUID.1F handling
> code,
> together with some related fixes and document updates.
>
>
Hi,

These patches are mainly bug fixes for ADL-N and Intel Hybrid
platforms.
May I know if there are any further changes needed?

thanks,
rui


> thanks,
> -rui
>
> ---
> Changes since V1:
> - fix/improve changelog/comment wording issues
> - reorder the patches to eliminate bisection breakage window
> - add a new patch for coretemp driver variable renaming
> - update coretemp driver patch to fix a case of ida_free(&ida, -2)