linux/arch/powerpc
Nicholas Piggin 1945bc4549 powerpc/64s: Fix POWER9 machine check handler from stop state
The ISA specifies power save wakeup due to a machine check exception can
cause a machine check interrupt (rather than the usual system reset
interrupt).

The machine check handler copes with this by doing low level machine
check recovery without restoring full state from idle, then queues up a
machine check event for logging, then directly executes the same idle
instruction it woke from. This minimises the work done before recovery
is performed.

The problem is that it requires machine specific instructions and
knowledge of the book3s idle code. Currently it only has code to handle
POWER8 idle, so POWER9 crashes when trying to execute the P8 idle
instructions which don't exist in ISAv3.0B.

cpu 0x0: Vector: e40 (Emulation Assist) at [c0000000008f3810]
    pc: c000000000008380: machine_check_handle_early+0x130/0x2f0
    lr: c00000000053a098: stop_loop+0x68/0xd0
    sp: c0000000008f3a90
   msr: 9000000000081001
  current = 0xc0000000008a1080
  paca    = 0xc00000000ffd0000   softe: 0        irq_happened: 0x01
    pid   = 0, comm = swapper/0

Instead of going to sleep after recovery, do the usual idle wakeup and
state restoration by calling into the normal idle wakeup path. This
reuses the normal idle wakeup paths.

Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Reviewed-by: Mahesh J Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-23 20:31:46 +10:00
..
boot powerpc/boot: Fix zImage TOC alignment 2017-03-08 10:39:32 +11:00
configs powerpc/configs: Re-enable POWER8 crc32c 2017-03-28 10:52:04 +11:00
crypto crypto: powerpc - Fix initialisation of crc32c context 2017-03-08 14:01:08 +08:00
include powerpc/64s: Fix POWER9 machine check handler from stop state 2017-04-23 20:31:46 +10:00
kernel powerpc/64s: Fix POWER9 machine check handler from stop state 2017-04-23 20:31:46 +10:00
kvm Merge branch 'topic/xive' (early part) into next 2017-04-12 22:31:37 +10:00
lib powerpc fixes for 4.11 #3 2017-03-07 10:46:10 -08:00
math-emu Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
mm powerpc/mm: Add support for runtime configuration of ASLR limits 2017-04-21 22:57:55 +10:00
net powerpc updates for 4.11 part 1. 2017-02-22 10:30:38 -08:00
oprofile ktime: Cleanup ktime_set() usage 2016-12-25 17:21:22 +01:00
perf powerpc/perf: Add Power8 mem_access event to sysfs 2017-04-19 20:00:23 +10:00
platforms powerpc/64s: Stop using bit in HSPRG0 to test winkle 2017-04-23 20:31:39 +10:00
purgatory kexec, x86/purgatory: Unbreak it and clean it up 2017-03-10 20:55:09 +01:00
scripts powerpc/ftrace: Add Kconfig & Make glue for mprofile-kernel 2016-03-07 14:53:56 +11:00
sysdev powerpc/xive: Fix missing check of rc != OPAL_BUSY 2017-04-20 14:43:19 +10:00
xmon Merge branch 'topic/xive' (early part) into next 2017-04-12 22:31:37 +10:00
Kconfig powerpc/mm: Add support for runtime configuration of ASLR limits 2017-04-21 22:57:55 +10:00
Kconfig.debug powerpc/xmon: Enable disassembly files (compilation changes) 2017-02-15 20:02:42 +11:00
Makefile powerpc: Fix compiling a BE kernel with a powerpc64le toolchain 2017-03-03 11:24:50 +11:00
relocs_check.sh powerpc/64: whitelist unresolved modversions CRCs 2016-09-22 14:46:31 +02:00