From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> Subject: powerpc / eeh_driver: Use global PCI rescan-remove locking Race conditions are theoretically possible between the PCI device addition and removal in the PPC64 PCI error recovery driver and the generic PCI bus rescan and device removal that can be triggered via sysfs. To avoid those race conditions make PPC64 PCI error recovery driver use global PCI rescan-remove locking around PCI device addition and removal. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> --- The previous version had wrong function names in the last hunk, sorry about that. Rafael --- arch/powerpc/kernel/eeh_driver.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) Index: linux-pm/arch/powerpc/kernel/eeh_driver.c =================================================================== --- linux-pm.orig/arch/powerpc/kernel/eeh_driver.c +++ linux-pm/arch/powerpc/kernel/eeh_driver.c @@ -369,7 +369,9 @@ static void *eeh_rmv_device(void *data, edev->mode |= EEH_DEV_DISCONNECTED; (*removed)++; + pci_lock_rescan_remove(); pci_stop_and_remove_bus_device(dev); + pci_unlock_rescan_remove(); return NULL; } @@ -416,10 +418,13 @@ static int eeh_reset_device(struct eeh_p * into pcibios_add_pci_devices(). */ eeh_pe_state_mark(pe, EEH_PE_KEEP); - if (bus) + if (bus) { + pci_lock_rescan_remove(); pcibios_remove_pci_devices(bus); - else if (frozen_bus) + pci_unlock_rescan_remove(); + } else if (frozen_bus) { eeh_pe_dev_traverse(pe, eeh_rmv_device, &removed); + } /* Reset the pci controller. (Asserts RST#; resets config space). * Reconfigure bridges and devices. Don't try to bring the system @@ -429,6 +434,8 @@ static int eeh_reset_device(struct eeh_p if (rc) return rc; + pci_lock_rescan_remove(); + /* Restore PE */ eeh_ops->configure_bridge(pe); eeh_pe_restore_bars(pe); @@ -462,6 +469,7 @@ static int eeh_reset_device(struct eeh_p pe->tstamp = tstamp; pe->freeze_count = cnt; + pci_unlock_rescan_remove(); return 0; } @@ -618,8 +626,11 @@ perm_error: eeh_pe_dev_traverse(pe, eeh_report_failure, NULL); /* Shut down the device drivers for good. */ - if (frozen_bus) + if (frozen_bus) { + pci_lock_rescan_remove(); pcibios_remove_pci_devices(frozen_bus); + pci_unlock_rescan_remove(); + } } static void eeh_handle_special_event(void) @@ -692,6 +703,7 @@ static void eeh_handle_special_event(voi if (rc == 2 || rc == 1) eeh_handle_normal_event(pe); else { + pci_lock_rescan_remove(); list_for_each_entry_safe(hose, tmp, &hose_list, list_node) { phb_pe = eeh_phb_pe_get(hose); @@ -703,6 +715,7 @@ static void eeh_handle_special_event(voi eeh_pe_dev_traverse(pe, eeh_report_failure, NULL); pcibios_remove_pci_devices(bus); } + pci_unlock_rescan_remove(); } } -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html