powerpc/powernv: Fix killed EEH event
commit5c7a35e3e25232aef8d7aee484436f8cbe3b9b94
authorGavin Shan <gwshan@linux.vnet.ibm.com>
Wed, 4 Jun 2014 07:31:52 +0000 (4 17:31 +1000)
committerBenjamin Herrenschmidt <benh@kernel.crashing.org>
Wed, 11 Jun 2014 07:04:33 +0000 (11 17:04 +1000)
tree7bf01ffd5b9e4057089c2c2383fbcf492694fca9
parent6e0fdf9af216887e0032c19d276889aad41cad00
powerpc/powernv: Fix killed EEH event

On PowerNV platform, EEH errors are reported by IO accessors or poller
driven by interrupt. After the PE is isolated, we won't produce EEH
event for the PE. The current implementation has possibility of EEH
event lost in this way:

The interrupt handler queues one "special" event, which drives the poller.
EEH thread doesn't pick the special event yet. IO accessors kicks in, the
frozen PE is marked as "isolated" and EEH event is queued to the list.
EEH thread runs because of special event and purge all existing EEH events.
However, we never produce an other EEH event for the frozen PE. Eventually,
the PE is marked as "isolated" and we don't have EEH event to recover it.

The patch fixes the issue to keep EEH events for PEs that have been
marked as "isolated" with the help of additional "force" help to
eeh_remove_event().

Reported-by: Rolf Brudeseth <rolfb@us.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
arch/powerpc/include/asm/eeh_event.h
arch/powerpc/kernel/eeh_driver.c
arch/powerpc/kernel/eeh_event.c
arch/powerpc/platforms/powernv/eeh-ioda.c