diff options
| author | Zhang Rui <rui.zhang@intel.com> | 2022-10-14 11:01:46 +0200 |
|---|---|---|
| committer | Dave Hansen <dave.hansen@linux.intel.com> | 2022-10-17 20:58:52 +0200 |
| commit | 2b12a7a126d62bdbd81f4923c21bf6e9a7fbd069 (patch) | |
| tree | 6725c79df9b15c582f433332307c38e8974e1e20 /arch | |
| parent | hwmon/coretemp: Handle large core ID value (diff) | |
| download | linux-2b12a7a126d62bdbd81f4923c21bf6e9a7fbd069.tar.xz linux-2b12a7a126d62bdbd81f4923c21bf6e9a7fbd069.zip | |
x86/topology: Fix multiple packages shown on a single-package system
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: 7745f03eb395 ("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
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kernel/cpu/topology.c | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/arch/x86/kernel/cpu/topology.c b/arch/x86/kernel/cpu/topology.c index 132a2de44d2f..f7592814e5d5 100644 --- a/arch/x86/kernel/cpu/topology.c +++ b/arch/x86/kernel/cpu/topology.c @@ -96,6 +96,7 @@ int detect_extended_topology(struct cpuinfo_x86 *c) unsigned int ht_mask_width, core_plus_mask_width, die_plus_mask_width; unsigned int core_select_mask, core_level_siblings; unsigned int die_select_mask, die_level_siblings; + unsigned int pkg_mask_width; bool die_level_present = false; int leaf; @@ -111,10 +112,10 @@ int detect_extended_topology(struct cpuinfo_x86 *c) core_level_siblings = smp_num_siblings = LEVEL_MAX_SIBLINGS(ebx); core_plus_mask_width = ht_mask_width = BITS_SHIFT_NEXT_LEVEL(eax); die_level_siblings = LEVEL_MAX_SIBLINGS(ebx); - die_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax); + pkg_mask_width = die_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax); sub_index = 1; - do { + while (true) { cpuid_count(leaf, sub_index, &eax, &ebx, &ecx, &edx); /* @@ -132,8 +133,13 @@ int detect_extended_topology(struct cpuinfo_x86 *c) die_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax); } + if (LEAFB_SUBTYPE(ecx) != INVALID_TYPE) + pkg_mask_width = BITS_SHIFT_NEXT_LEVEL(eax); + else + break; + sub_index++; - } while (LEAFB_SUBTYPE(ecx) != INVALID_TYPE); + } core_select_mask = (~(-1 << core_plus_mask_width)) >> ht_mask_width; die_select_mask = (~(-1 << die_plus_mask_width)) >> @@ -148,7 +154,7 @@ int detect_extended_topology(struct cpuinfo_x86 *c) } c->phys_proc_id = apic->phys_pkg_id(c->initial_apicid, - die_plus_mask_width); + pkg_mask_width); /* * Reinit the apicid, now that we have extended initial_apicid. */ |