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. Patch 1/7 and 2/7 fix the first two issues. And at the same time, it reveals a reality that the core_id could be sparse on platforms with CPUID.1F support. Patch 3/7 improves coretemp driver code to be able to handle sparse core id, which is the only driver that uses core_id as array index and run on platforms with CPUID.1F support. Patch 4/7 to 7/7 propose a fix for the third problem and update the related Documents. The patch series have been tested on Intel ICL/CLX servers, SKL/KBL/ADL clients. thanks, -rui
