powerpc/eeh: Wrong place to call pci_get_slot()
pci_get_slot() is called with hold of PCI bus semaphore and it's not
safe to be called in interrupt context. However, we possibly checks
EEH error and calls the function in interrupt context. To avoid using
pci_get_slot(), we turn into device tree for fetching location code.
Otherwise, we might run into WARN_ON() as following messages indicate:
WARNING: at drivers/pci/search.c:223
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.16.0-rc3+ #72
task:
c000000001367af0 ti:
c000000001444000 task.ti:
c000000001444000
NIP:
c000000000497b70 LR:
c000000000037530 CTR:
000000003003d114
REGS:
c000000001446fa0 TRAP: 0700 Not tainted (3.16.0-rc3+)
MSR:
9000000000029032 <SF,HV,EE,ME,IR,DR,RI> CR:
48002422 XER:
20000000
CFAR:
c00000000003752c SOFTE: 0
:
NIP [
c000000000497b70] .pci_get_slot+0x40/0x110
LR [
c000000000037530] .eeh_pe_loc_get+0x150/0x190
Call Trace:
.of_get_property+0x30/0x60 (unreliable)
.eeh_pe_loc_get+0x150/0x190
.eeh_dev_check_failure+0x1b4/0x550
.eeh_check_failure+0x90/0xf0
.lpfc_sli_check_eratt+0x504/0x7c0 [lpfc]
.lpfc_poll_eratt+0x64/0x100 [lpfc]
.call_timer_fn+0x64/0x190
.run_timer_softirq+0x2cc/0x3e0
Cc: stable@vger.kernel.org
Signed-off-by: Mike Qiu <qiudayu@linux.vnet.ibm.com>
Acked-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>