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Commit d31f4bc2 authored by Zhang Rui's avatar Zhang Rui Committed by Greg Kroah-Hartman
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x86/topology: Fix multiple packages shown on a single-package system

commit 2b12a7a1 upstream.

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: 7745f03e

 ("x86/topology: Add CPUID.1F multi-die/package support")
Suggested-by: default avatarLen Brown <len.brown@intel.com>
Signed-off-by: default avatarZhang Rui <rui.zhang@intel.com>
Signed-off-by: default avatarDave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: default avatarLen 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: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent fcc96e89
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