fadump: Reserve the memory for firmware assisted dump.
authorMahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Thu, 16 Feb 2012 01:14:22 +0000 (01:14 +0000)
committerBenjamin Herrenschmidt <benh@kernel.crashing.org>
Wed, 22 Feb 2012 23:50:01 +0000 (10:50 +1100)
commiteb39c8803d0e3d98fe74825f99287f63d55e6460
treecf157bb2bb5271aaf1823e9ee3b91800c00c8b05
parent8e0aa6d436f303a37df7ec68758883ade077d123
fadump: Reserve the memory for firmware assisted dump.

Reserve the memory during early boot to preserve CPU state data, HPTE region
and RMA (real mode area) region data in case of kernel crash. At the time of
crash, powerpc firmware will store CPU state data, HPTE region data and move
RMA region data to the reserved memory area.

If the firmware-assisted dump fails to reserve the memory, then fallback
to existing kexec-based kdump.

Most of the code implementation to reserve memory has been
adapted from phyp assisted dump implementation written by Linas Vepstas
and Manish Ahuja

This patch also introduces a config option CONFIG_FA_DUMP for firmware
assisted dump feature on Powerpc (ppc64) architecture.

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
arch/powerpc/Kconfig
arch/powerpc/include/asm/fadump.h [new file with mode: 0644]
arch/powerpc/kernel/Makefile
arch/powerpc/kernel/fadump.c [new file with mode: 0644]
arch/powerpc/kernel/prom.c