[PATCH 0/3] x86: Fix panic vs. NMI issues

[Hidehiro Kawai]

When an HA cluster software or administrator detects non-response
of a host, they issue an NMI to the host to completely stop current
works and take a crash dump.  If the kernel has already panicked
or is capturing a crash dump at that time, further NMI can cause
a crash dump failure.

To solve this issue, this patch set does two things:

- Don't panic on NMI if the kernel has already panicked
- Introduce "noextnmi" boot option which masks external NMI at the
  boot time (supported only for x86)

---

Hidehiro Kawai (3):
      x86/panic: Fix re-entrance problem due to panic on NMI
      kexec: Fix race between panic() and crash_kexec() directly called
      x86/apic: Introduce noextnmi boot option


 Documentation/kernel-parameters.txt |    4 ++++
 arch/x86/kernel/apic/apic.c         |   17 +++++++++++++++-
 arch/x86/kernel/nmi.c               |   18 +++++++++++------
 include/linux/kernel.h              |    4 ++++
 include/linux/kexec.h               |    2 ++
 kernel/kexec.c                      |   12 ++++++++++-
 kernel/panic.c                      |   37 ++++++++++++++++++++++++++---------
 7 files changed, 76 insertions(+), 18 deletions(-)


-- 
Hidehiro Kawai
Hitachi, Ltd. Research & Development Group