]> git.karo-electronics.de Git - linux-beck.git/commit
powerpc/eeh: Fix stale cached primary bus
authorGavin Shan <gwshan@linux.vnet.ibm.com>
Tue, 9 Feb 2016 04:50:21 +0000 (15:50 +1100)
committerMichael Ellerman <mpe@ellerman.id.au>
Mon, 15 Feb 2016 10:10:04 +0000 (21:10 +1100)
commit05ba75f848647135f063199dc0e9f40fee769724
treed97694ef04ca093796032df20621732d229ec0f1
parent126df08c52375817c237f38c3bcd01d78a60c090
powerpc/eeh: Fix stale cached primary bus

When PE is created, its primary bus is cached to pe->bus. At later
point, the cached primary bus is returned from eeh_pe_bus_get().
However, we could get stale cached primary bus and run into kernel
crash in one case: full hotplug as part of fenced PHB error recovery
releases all PCI busses under the PHB at unplugging time and recreate
them at plugging time. pe->bus is still dereferencing the PCI bus
that was released.

This adds another PE flag (EEH_PE_PRI_BUS) to represent the validity
of pe->bus. pe->bus is updated when its first child EEH device is
online and the flag is set. Before unplugging in full hotplug for
error recovery, the flag is cleared.

Fixes: 8cdb2833 ("powerpc/eeh: Trace PCI bus from PE")
Cc: stable@vger.kernel.org #v3.11+
Reported-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reported-by: Pradipta Ghosh <pradghos@in.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Tested-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
arch/powerpc/include/asm/eeh.h
arch/powerpc/kernel/eeh_driver.c
arch/powerpc/kernel/eeh_pe.c
arch/powerpc/platforms/powernv/eeh-powernv.c