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

From: HATAYAMA Daisuke
Date: Wed Oct 16 2013 - 08:52:22 EST


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
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