FAILED: patch "[PATCH] x86/topology: Fix duplicated core ID within a package" failed to apply to 5.4-stable tree
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[email protected]
maintainerThe patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.
Possible dependencies:
71eac7063698 ("x86/topology: Fix duplicated core ID within a package")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 71eac7063698b7d7b8fafb1683ac24a034541141 Mon Sep 17 00:00:00 2001
From: Zhang Rui <[email protected]>
Date: Fri, 14 Oct 2022 17:01:47 +0800
Subject: [PATCH] x86/topology: Fix duplicated core ID within a package
Today, core ID is assumed to be unique within each package.
But an AlderLake-N platform adds a Module level between core and package, Linux excludes the unknown modules bits from the core ID, resulting in duplicate core ID's.
To keep core ID unique within a package, Linux must include all APIC-ID bits for known or unknown levels above the core and below the package in the core ID.
It is important to understand that core ID's have always come directly from the APIC-ID encoding, which comes from the BIOS. Thus there is no guarantee that they start at 0, or that they are contiguous. As such, naively using them for array indexes can be problematic.
[ dhansen: un-known -> unknown ]
arch/x86/kernel/cpu/topology.c +1 -1
@@ -141,7 +141,7 @@ int detect_extended_topology(struct cpuinfo_x86 *c) sub_index++; } - core_select_mask = (~(-1 << core_plus_mask_width)) >> ht_mask_width; + core_select_mask = (~(-1 << pkg_mask_width)) >> ht_mask_width; die_select_mask = (~(-1 << die_plus_mask_width)) >> core_plus_mask_width;