6c31fc028a
[ Upstream commit2b12a7a126] CPUID.1F/B does not enumerate Package level explicitly, instead, all the APIC-ID bits above the enumerated levels are assumed to be package ID bits. Current code gets package ID by shifting out all the APIC-ID bits that Linux supports, rather than shifting out all the APIC-ID bits that CPUID.1F enumerates. This introduces problems when CPUID.1F enumerates a level that Linux does not support. For example, on a single package AlderLake-N, there are 2 Ecore Modules with 4 atom cores in each module. Linux does not support the Module level and interprets the Module ID bits as package ID and erroneously reports a multi module system as a multi-package system. Fix this by using APIC-ID bits above all the CPUID.1F enumerated levels as package ID. [ dhansen: spelling fix ] Fixes:7745f03eb3("x86/topology: Add CPUID.1F multi-die/package support") Suggested-by: Len Brown <len.brown@intel.com> Signed-off-by: Zhang Rui <rui.zhang@intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Len Brown <len.brown@intel.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20221014090147.1836-4-rui.zhang@intel.com Signed-off-by: Sasha Levin <sashal@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.