[Patch 0/7] V2 Implement crashkernel=auto

[Amerigo Wang <amwang@redhat.com>]

V1 -> V2:
 - Use include/asm-generic/kexec.h, suggested by Neil.
 - Rename a local variable, suggested by Fenghua.
 - Fix some style problems found by checkpatch.pl.
 - Unify the Kconfig docs.

This series of patch implements automatically reserved memory for crashkernel,
by introducing a new boot option "crashkernel=auto". This idea is from Neil.

In case of breaking user-space applications, it modifies this boot option after
it decides how much memory should be reserved.

On different arch, the threshold and reserved memory size is different. Please
refer patch 7/7 which contains an update for the documentation.

Note: This patchset was only tested on x86_64 with differernt memory sizes.

Signed-off-by: WANG Cong <amwang@redhat.com>
Cc: Neil Horman <nhorman@redhat.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Anton Vorontsov <avorontsov@ru.mvista.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Fenghua Yu <fenghua.yu@intel.com>

---
 Documentation/kdump/kdump.txt    |   16 ++++++++++++++++
 arch/ia64/Kconfig                |   10 ++++++++++
 arch/ia64/include/asm/kexec.h    |    8 ++++++++
 arch/powerpc/Kconfig             |   10 ++++++++++
 arch/powerpc/include/asm/kexec.h |    8 ++++++++
 arch/x86/Kconfig                 |   10 ++++++++++
 arch/x86/include/asm/kexec.h     |    1 +
 kernel/kexec.c                   |   34 ++++++++++++++++++++++++++++++++++
 8 files changed, 97 insertions(+)