linux-sg2042/arch/powerpc/xmon
Michael Ellerman 7b08729cb2 powerpc/64: Save stack pointer when we hard disable interrupts
A CPU that gets stuck with interrupts hard disable can be difficult to
debug, as on some platforms we have no way to interrupt the CPU to
find out what it's doing.

A stop-gap is to have the CPU save it's stack pointer (r1) in its paca
when it hard disables interrupts. That way if we can't interrupt it,
we can at least trace the stack based on where it last disabled
interrupts.

In some cases that will be total junk, but the stack trace code should
handle that. In the simple case of a CPU that disable interrupts and
then gets stuck in a loop, the stack trace should be informative.

We could clear the saved stack pointer when we enable interrupts, but
that loses information which could be useful if we have nothing else
to go on.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
2018-06-03 20:43:42 +10:00
..
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
ansidecl.h
dis-asm.h [POWERPC] Make xmon disassembly optional 2006-12-04 20:40:32 +11:00
nonstdio.c powerpc/xmon: Paged output for paca display 2015-10-15 20:32:01 +11:00
nonstdio.h powerpc/xmon: Add __printf annotation to xmon_printf() 2018-05-25 12:04:36 +10:00
ppc-dis.c powerpc/xmon: Do not compute/store the major opcode 2018-01-21 23:37:43 +11:00
ppc-opc.c powerpc updates for 4.11 part 2 2017-03-01 10:10:16 -08:00
ppc.h powerpc/xmon: Enable disassembly files (compilation changes) 2017-02-15 20:02:42 +11:00
spr_access.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
spu-dis.c powerpc/xmon: Add __printf annotation to xmon_printf() 2018-05-25 12:04:36 +10:00
spu-insns.h [POWERPC] Import spu disassembly code into xmon 2006-12-04 20:40:29 +11:00
spu-opc.c bug.h: add include of it to various implicit C users 2012-02-29 17:15:08 -05:00
spu.h [POWERPC] Import spu disassembly code into xmon 2006-12-04 20:40:29 +11:00
xmon.c powerpc/64: Save stack pointer when we hard disable interrupts 2018-06-03 20:43:42 +10:00