powerpc/eeh: Fix invalid cached PE primary bus

The PE primary bus cannot be got from its child devices when having
full hotplug in error recovery. The PE primary bus is cached, which
is done in commit <05ba75f84864> ("powerpc/eeh: Fix stale cached primary
bus"). In eeh_reset_device(), the flag (EEH_PE_PRI_BUS) is cleared
before the PCI hot remove. eeh_pe_bus_get() then returns NULL as the
PE primary bus in pnv_eeh_reset() and it crashes the kernel eventually.

This fixes the issue by clearing the flag (EEH_PE_PRI_BUS) before the
PCI hot add. With it, the PowerNV EEH reset backend (pnv_eeh_reset())
can get valid PE primary bus through eeh_pe_bus_get().

Fixes: 67086e32b5 ("powerpc/eeh: powerpc/eeh: Support error recovery for VF PE")
Reported-by: Pridhiviraj Paidipeddi <ppaiddipe@in.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Gavin Shan 2016-06-17 13:05:11 +10:00 committed by Michael Ellerman
parent b23d9c5b9c
commit a3aa256b72
1 changed files with 4 additions and 3 deletions

View File

@ -642,7 +642,6 @@ static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus,
if (pe->type & EEH_PE_VF) {
eeh_pe_dev_traverse(pe, eeh_rmv_device, NULL);
} else {
eeh_pe_state_clear(pe, EEH_PE_PRI_BUS);
pci_lock_rescan_remove();
pci_hp_remove_devices(bus);
pci_unlock_rescan_remove();
@ -692,10 +691,12 @@ static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus,
*/
edev = list_first_entry(&pe->edevs, struct eeh_dev, list);
eeh_pe_traverse(pe, eeh_pe_detach_dev, NULL);
if (pe->type & EEH_PE_VF)
if (pe->type & EEH_PE_VF) {
eeh_add_virt_device(edev, NULL);
else
} else {
eeh_pe_state_clear(pe, EEH_PE_PRI_BUS);
pci_hp_add_devices(bus);
}
} else if (frozen_bus && rmv_data->removed) {
pr_info("EEH: Sleep 5s ahead of partial hotplug\n");
ssleep(5);