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[PATCH v4 0/2] Fix how CPUs are enumerated when there's more than 255 CPUs

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This series of patches attempts to fix how CPUs are enumerated by kernel when
there's more than 255 of them on single processor.
In such case, BIOS may interleave APIC/X2APIC MADT subtables, to obey requirements
specified in ACPI spec. Without this patches, kernel then would first enumerate
BSP, then X2APIC then APIC, resulting in low APIC IDs to be assigned with high
logical IDs and high APIC IDs to be assigned low logical IDs. Biggest consequence
of that could be performance penalties due to wrong L2 cache sharing.
More details in patch 2/2.

Also, simpler approach has been considered, which did not required ACPI parsing
interface changes, however it failed to meet requirements. More details can be
found here: https://lkml.org/lkml/2015/9/7/285

Lukasz Anaczkowski (2):
  acpi: Added acpi_subtable_proc to ACPI table parsers
  x86, acpi: Handle apic/x2apic entries in MADT in correct order

 arch/x86/kernel/acpi/boot.c | 22 +++++++++--
 drivers/acpi/tables.c       | 91 ++++++++++++++++++++++++++++++++++++---------
 include/linux/acpi.h        | 19 ++++++++--
 3 files changed, 107 insertions(+), 25 deletions(-)

-- 
1.8.3.1

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Re: [PATCH] x86, arm64, acpi: Handle lapic/x2apic entries in MADT Lukasz Anaczkowski <lukasz.anaczkowski@intel.com> - 2015-09-08 13:10 +0200
  [PATCH 1/4] acpi: rename acpi_table_parse_entries Lukasz Anaczkowski <lukasz.anaczkowski@intel.com> - 2015-09-08 13:10 +0200
  [PATCH 0/4] Fix how CPUs are enumerated when there's more than 255 CPUs Lukasz Anaczkowski <lukasz.anaczkowski@intel.com> - 2015-09-08 13:10 +0200
    Re: [PATCH 0/4] Fix how CPUs are enumerated when there's more than  255 CPUs Marc Zyngier <marc.zyngier@arm.com> - 2015-09-08 18:30 +0200
      Re: [PATCH 0/4] Fix how CPUs are enumerated when there's more than  255 CPUs Al Stone <ahs3@redhat.com> - 2015-09-09 00:50 +0200
      RE: [PATCH 0/4] Fix how CPUs are enumerated when there's more than  255 CPUs "Anaczkowski, Lukasz" <lukasz.anaczkowski@intel.com> - 2015-09-09 09:10 +0200
      [PATCH 1/2] acpi: Added acpi_subtable_proc to ACPI table parsers Lukasz Anaczkowski <lukasz.anaczkowski@intel.com> - 2015-09-09 11:40 +0200
        [PATCH 2/2] x86, acpi: Handle apic/x2apic entries in MADT in correct order Lukasz Anaczkowski <lukasz.anaczkowski@intel.com> - 2015-09-09 11:40 +0200
          Re: [PATCH 2/2] x86, acpi: Handle apic/x2apic entries in MADT in  correct order Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> - 2015-09-09 16:00 +0200
            RE: [PATCH 2/2] x86, acpi: Handle apic/x2apic entries in MADT in  correct order "Anaczkowski, Lukasz" <lukasz.anaczkowski@intel.com> - 2015-09-09 16:40 +0200
              Re: [PATCH 2/2] x86, acpi: Handle apic/x2apic entries in MADT in  correct order Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> - 2015-09-09 17:50 +0200
        Re: [PATCH 1/2] acpi: Added acpi_subtable_proc to ACPI table parsers Marc Zyngier <marc.zyngier@arm.com> - 2015-09-09 12:50 +0200
          [PATCH v4 0/2] Fix how CPUs are enumerated when there's more than 255 CPUs Lukasz Anaczkowski <lukasz.anaczkowski@intel.com> - 2015-09-09 15:50 +0200
            [PATCH v4 1/2] acpi: Added acpi_subtable_proc to ACPI table parsers Lukasz Anaczkowski <lukasz.anaczkowski@intel.com> - 2015-09-09 15:50 +0200
              [PATCH v4 2/2] x86, acpi: Handle apic/x2apic entries in MADT in correct order Lukasz Anaczkowski <lukasz.anaczkowski@intel.com> - 2015-09-09 15:50 +0200
            Re: [PATCH v4 0/2] Fix how CPUs are enumerated when there's more than 255 CPUs "Rafael J. Wysocki" <rjw@rjwysocki.net> - 2015-09-09 22:20 +0200
              Re: [PATCH v4 0/2] Fix how CPUs are enumerated when there's more than 255 CPUs "Rafael J. Wysocki" <rjw@rjwysocki.net> - 2015-09-19 00:20 +0200
          Re: [PATCH 1/2] acpi: Added acpi_subtable_proc to ACPI table parsers Lukasz Anaczkowski <lukasz.anaczkowski@intel.com> - 2015-09-09 15:50 +0200
      [PATCH 0/2] Fix how CPUs are enumerated when there's more than 255 CPUs Lukasz Anaczkowski <lukasz.anaczkowski@intel.com> - 2015-09-09 11:40 +0200

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