[PATCH v3 0/2] x86, apic, kdump: Disable BSP if boot cpu is AP

[HATAYAMA Daisuke]

This patch set is to allow kdump 2nd kernel to wake up multiple CPUs
even if 1st kernel crashs on some AP.

Sorry, this patch set have not include in-source documentation
requested by Borislav Petkov yet, but I'll post it later separately,
which would be better to focus on documentation reviewing.

ChangeLog

v2 => v3)

- Change default value of boot_cpu_is_bsp to true.

- Before executing rdmsr(MSR_IA32_APICBASE), check if the number of
  processor family is larger than or equal to 6 in order to avoid
  invalid opcode exception on processors where MSR_IA32_APICBASE is
  not supported.

v1 => v2)

- Rebased on top of v3.12-rc5.

- Fix linking time error of boot_cpu_is_bsp_init() in case of
  CONFIG_LOCAL_APIC disabled by adding empty static inline function
  instead.

- Fix missing feature check by means of cpu_has_apic macro in
  boot_cpu_is_bsp_init() before calling rdmsr_safe(MSR_IA32_APICBASE).

  NOTE: I've checked local apic-present case only; I don't have any
  x86 processor without local apic.

- Add __init annotation to boot_cpu_is_bsp_init().

Test

- built with and without CONFIG_LOCAL_APIC
- tested x86_64 in case of acpi and MP table

---

HATAYAMA Daisuke (2):
      x86, apic: Add boot_cpu_is_bsp() to check if boot cpu is BSP
      x86, apic: Disable BSP if boot cpu is AP


 arch/x86/include/asm/mpspec.h |    9 ++++++++-
 arch/x86/kernel/acpi/boot.c   |    6 +++++-
 arch/x86/kernel/apic/apic.c   |   35 ++++++++++++++++++++++++++++++++++-
 arch/x86/kernel/devicetree.c  |    1 +
 arch/x86/kernel/mpparse.c     |   15 +++++++++++++--
 arch/x86/kernel/setup.c       |    2 ++
 arch/x86/platform/sfi/sfi.c   |    2 +-
 7 files changed, 64 insertions(+), 6 deletions(-)

-- 

Thanks.
HATAYAMA, Daisuke