fadump: Convert firmware-assisted cpu state dump data into elf notes.

When registered for firmware assisted dump on powerpc, firmware preserves
the registers for the active CPUs during a system crash. This patch reads
the cpu register data stored in Firmware-assisted dump format (except for
crashing cpu) and converts it into elf notes and updates the PT_NOTE program
header accordingly. The exact register state for crashing cpu is saved to
fadump crash info structure in scratch area during crash_fadump() and read
during second kernel boot.

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Mahesh Salgaonkar 2012-02-16 01:14:45 +00:00 committed by Benjamin Herrenschmidt
parent 2df173d9e8
commit ebaeb5ae24
4 changed files with 365 additions and 2 deletions

View file

@ -61,6 +61,7 @@
#include <asm/xmon.h>
#include <asm/cputhreads.h>
#include <mm/mmu_decl.h>
#include <asm/fadump.h>
#include "setup.h"
@ -639,6 +640,11 @@ EXPORT_SYMBOL(check_legacy_ioport);
static int ppc_panic_event(struct notifier_block *this,
unsigned long event, void *ptr)
{
/*
* If firmware-assisted dump has been registered then trigger
* firmware-assisted dump and let firmware handle everything else.
*/
crash_fadump(NULL, ptr);
ppc_md.panic(ptr); /* May not return */
return NOTIFY_DONE;
}