1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * PCI Error Recovery Driver for RPA-compliant PPC64 platform.
4 * Copyright IBM Corp. 2004 2005
5 * Copyright Linas Vepstas <linas@linas.org> 2004, 2005
7 * Send comments and feedback to Linas Vepstas <linas@austin.ibm.com>
9 #include <linux/delay.h>
10 #include <linux/interrupt.h>
11 #include <linux/irq.h>
12 #include <linux/module.h>
13 #include <linux/pci.h>
14 #include <linux/pci_hotplug.h>
16 #include <asm/eeh_event.h>
17 #include <asm/ppc-pci.h>
18 #include <asm/pci-bridge.h>
23 struct list_head removed_vf_list;
24 int removed_dev_count;
27 static int eeh_result_priority(enum pci_ers_result result)
30 case PCI_ERS_RESULT_NONE:
32 case PCI_ERS_RESULT_NO_AER_DRIVER:
34 case PCI_ERS_RESULT_RECOVERED:
36 case PCI_ERS_RESULT_CAN_RECOVER:
38 case PCI_ERS_RESULT_DISCONNECT:
40 case PCI_ERS_RESULT_NEED_RESET:
43 WARN_ONCE(1, "Unknown pci_ers_result value: %d\n", (int)result);
48 static const char *pci_ers_result_name(enum pci_ers_result result)
51 case PCI_ERS_RESULT_NONE:
53 case PCI_ERS_RESULT_CAN_RECOVER:
55 case PCI_ERS_RESULT_NEED_RESET:
57 case PCI_ERS_RESULT_DISCONNECT:
59 case PCI_ERS_RESULT_RECOVERED:
61 case PCI_ERS_RESULT_NO_AER_DRIVER:
62 return "no AER driver";
64 WARN_ONCE(1, "Unknown result type: %d\n", (int)result);
69 static enum pci_ers_result pci_ers_merge_result(enum pci_ers_result old,
70 enum pci_ers_result new)
72 if (eeh_result_priority(new) > eeh_result_priority(old))
77 static bool eeh_dev_removed(struct eeh_dev *edev)
79 return !edev || (edev->mode & EEH_DEV_REMOVED);
82 static bool eeh_edev_actionable(struct eeh_dev *edev)
86 if (edev->pdev->error_state == pci_channel_io_perm_failure)
88 if (eeh_dev_removed(edev))
90 if (eeh_pe_passed(edev->pe))
97 * eeh_pcid_get - Get the PCI device driver
100 * The function is used to retrieve the PCI device driver for
101 * the indicated PCI device. Besides, we will increase the reference
102 * of the PCI device driver to prevent that being unloaded on
103 * the fly. Otherwise, kernel crash would be seen.
105 static inline struct pci_driver *eeh_pcid_get(struct pci_dev *pdev)
107 if (!pdev || !pdev->driver)
110 if (!try_module_get(pdev->driver->driver.owner))
117 * eeh_pcid_put - Dereference on the PCI device driver
120 * The function is called to do dereference on the PCI device
121 * driver of the indicated PCI device.
123 static inline void eeh_pcid_put(struct pci_dev *pdev)
125 if (!pdev || !pdev->driver)
128 module_put(pdev->driver->driver.owner);
132 * eeh_disable_irq - Disable interrupt for the recovering device
135 * This routine must be called when reporting temporary or permanent
136 * error to the particular PCI device to disable interrupt of that
137 * device. If the device has enabled MSI or MSI-X interrupt, we needn't
138 * do real work because EEH should freeze DMA transfers for those PCI
139 * devices encountering EEH errors, which includes MSI or MSI-X.
141 static void eeh_disable_irq(struct eeh_dev *edev)
143 /* Don't disable MSI and MSI-X interrupts. They are
144 * effectively disabled by the DMA Stopped state
145 * when an EEH error occurs.
147 if (edev->pdev->msi_enabled || edev->pdev->msix_enabled)
150 if (!irq_has_action(edev->pdev->irq))
153 edev->mode |= EEH_DEV_IRQ_DISABLED;
154 disable_irq_nosync(edev->pdev->irq);
158 * eeh_enable_irq - Enable interrupt for the recovering device
161 * This routine must be called to enable interrupt while failed
162 * device could be resumed.
164 static void eeh_enable_irq(struct eeh_dev *edev)
166 if ((edev->mode) & EEH_DEV_IRQ_DISABLED) {
167 edev->mode &= ~EEH_DEV_IRQ_DISABLED;
171 * This is just ass backwards. This maze has
172 * unbalanced irq_enable/disable calls. So instead of
173 * finding the root cause it works around the warning
174 * in the irq_enable code by conditionally calling
177 * That's just wrong.The warning in the core code is
178 * there to tell people to fix their asymmetries in
179 * their own code, not by abusing the core information
182 * I so wish that the assymetry would be the other way
183 * round and a few more irq_disable calls render that
184 * shit unusable forever.
188 if (irqd_irq_disabled(irq_get_irq_data(edev->pdev->irq)))
189 enable_irq(edev->pdev->irq);
193 static void eeh_dev_save_state(struct eeh_dev *edev, void *userdata)
195 struct pci_dev *pdev;
201 * We cannot access the config space on some adapters.
202 * Otherwise, it will cause fenced PHB. We don't save
203 * the content in their config space and will restore
204 * from the initial config space saved when the EEH
207 if (edev->pe && (edev->pe->state & EEH_PE_CFG_RESTRICTED))
210 pdev = eeh_dev_to_pci_dev(edev);
214 pci_save_state(pdev);
217 static void eeh_set_channel_state(struct eeh_pe *root, pci_channel_state_t s)
220 struct eeh_dev *edev, *tmp;
222 eeh_for_each_pe(root, pe)
223 eeh_pe_for_each_dev(pe, edev, tmp)
224 if (eeh_edev_actionable(edev))
225 edev->pdev->error_state = s;
228 static void eeh_set_irq_state(struct eeh_pe *root, bool enable)
231 struct eeh_dev *edev, *tmp;
233 eeh_for_each_pe(root, pe) {
234 eeh_pe_for_each_dev(pe, edev, tmp) {
235 if (!eeh_edev_actionable(edev))
238 if (!eeh_pcid_get(edev->pdev))
242 eeh_enable_irq(edev);
244 eeh_disable_irq(edev);
246 eeh_pcid_put(edev->pdev);
251 typedef enum pci_ers_result (*eeh_report_fn)(struct eeh_dev *,
253 struct pci_driver *);
254 static void eeh_pe_report_edev(struct eeh_dev *edev, eeh_report_fn fn,
255 enum pci_ers_result *result)
257 struct pci_dev *pdev;
258 struct pci_driver *driver;
259 enum pci_ers_result new_result;
261 pci_lock_rescan_remove();
264 get_device(&pdev->dev);
265 pci_unlock_rescan_remove();
267 eeh_edev_info(edev, "no device");
270 device_lock(&pdev->dev);
271 if (eeh_edev_actionable(edev)) {
272 driver = eeh_pcid_get(pdev);
275 eeh_edev_info(edev, "no driver");
276 else if (!driver->err_handler)
277 eeh_edev_info(edev, "driver not EEH aware");
278 else if (edev->mode & EEH_DEV_NO_HANDLER)
279 eeh_edev_info(edev, "driver bound too late");
281 new_result = fn(edev, pdev, driver);
282 eeh_edev_info(edev, "%s driver reports: '%s'",
284 pci_ers_result_name(new_result));
286 *result = pci_ers_merge_result(*result,
292 eeh_edev_info(edev, "not actionable (%d,%d,%d)", !!pdev,
293 !eeh_dev_removed(edev), !eeh_pe_passed(edev->pe));
295 device_unlock(&pdev->dev);
296 if (edev->pdev != pdev)
297 eeh_edev_warn(edev, "Device changed during processing!\n");
298 put_device(&pdev->dev);
301 static void eeh_pe_report(const char *name, struct eeh_pe *root,
302 eeh_report_fn fn, enum pci_ers_result *result)
305 struct eeh_dev *edev, *tmp;
307 pr_info("EEH: Beginning: '%s'\n", name);
308 eeh_for_each_pe(root, pe) eeh_pe_for_each_dev(pe, edev, tmp)
309 eeh_pe_report_edev(edev, fn, result);
311 pr_info("EEH: Finished:'%s' with aggregate recovery state:'%s'\n",
312 name, pci_ers_result_name(*result));
314 pr_info("EEH: Finished:'%s'", name);
318 * eeh_report_error - Report pci error to each device driver
320 * @driver: device's PCI driver
322 * Report an EEH error to each device driver.
324 static enum pci_ers_result eeh_report_error(struct eeh_dev *edev,
325 struct pci_dev *pdev,
326 struct pci_driver *driver)
328 enum pci_ers_result rc;
330 if (!driver->err_handler->error_detected)
331 return PCI_ERS_RESULT_NONE;
333 eeh_edev_info(edev, "Invoking %s->error_detected(IO frozen)",
335 rc = driver->err_handler->error_detected(pdev, pci_channel_io_frozen);
337 edev->in_error = true;
338 pci_uevent_ers(pdev, PCI_ERS_RESULT_NONE);
343 * eeh_report_mmio_enabled - Tell drivers that MMIO has been enabled
345 * @driver: device's PCI driver
347 * Tells each device driver that IO ports, MMIO and config space I/O
350 static enum pci_ers_result eeh_report_mmio_enabled(struct eeh_dev *edev,
351 struct pci_dev *pdev,
352 struct pci_driver *driver)
354 if (!driver->err_handler->mmio_enabled)
355 return PCI_ERS_RESULT_NONE;
356 eeh_edev_info(edev, "Invoking %s->mmio_enabled()", driver->name);
357 return driver->err_handler->mmio_enabled(pdev);
361 * eeh_report_reset - Tell device that slot has been reset
363 * @driver: device's PCI driver
365 * This routine must be called while EEH tries to reset particular
366 * PCI device so that the associated PCI device driver could take
367 * some actions, usually to save data the driver needs so that the
368 * driver can work again while the device is recovered.
370 static enum pci_ers_result eeh_report_reset(struct eeh_dev *edev,
371 struct pci_dev *pdev,
372 struct pci_driver *driver)
374 if (!driver->err_handler->slot_reset || !edev->in_error)
375 return PCI_ERS_RESULT_NONE;
376 eeh_edev_info(edev, "Invoking %s->slot_reset()", driver->name);
377 return driver->err_handler->slot_reset(pdev);
380 static void eeh_dev_restore_state(struct eeh_dev *edev, void *userdata)
382 struct pci_dev *pdev;
388 * The content in the config space isn't saved because
389 * the blocked config space on some adapters. We have
390 * to restore the initial saved config space when the
391 * EEH device is created.
393 if (edev->pe && (edev->pe->state & EEH_PE_CFG_RESTRICTED)) {
394 if (list_is_last(&edev->entry, &edev->pe->edevs))
395 eeh_pe_restore_bars(edev->pe);
400 pdev = eeh_dev_to_pci_dev(edev);
404 pci_restore_state(pdev);
408 * eeh_report_resume - Tell device to resume normal operations
410 * @driver: device's PCI driver
412 * This routine must be called to notify the device driver that it
413 * could resume so that the device driver can do some initialization
414 * to make the recovered device work again.
416 static enum pci_ers_result eeh_report_resume(struct eeh_dev *edev,
417 struct pci_dev *pdev,
418 struct pci_driver *driver)
420 if (!driver->err_handler->resume || !edev->in_error)
421 return PCI_ERS_RESULT_NONE;
423 eeh_edev_info(edev, "Invoking %s->resume()", driver->name);
424 driver->err_handler->resume(pdev);
426 pci_uevent_ers(edev->pdev, PCI_ERS_RESULT_RECOVERED);
427 #ifdef CONFIG_PCI_IOV
428 if (eeh_ops->notify_resume)
429 eeh_ops->notify_resume(edev);
431 return PCI_ERS_RESULT_NONE;
435 * eeh_report_failure - Tell device driver that device is dead.
437 * @driver: device's PCI driver
439 * This informs the device driver that the device is permanently
440 * dead, and that no further recovery attempts will be made on it.
442 static enum pci_ers_result eeh_report_failure(struct eeh_dev *edev,
443 struct pci_dev *pdev,
444 struct pci_driver *driver)
446 enum pci_ers_result rc;
448 if (!driver->err_handler->error_detected)
449 return PCI_ERS_RESULT_NONE;
451 eeh_edev_info(edev, "Invoking %s->error_detected(permanent failure)",
453 rc = driver->err_handler->error_detected(pdev,
454 pci_channel_io_perm_failure);
456 pci_uevent_ers(pdev, PCI_ERS_RESULT_DISCONNECT);
460 static void *eeh_add_virt_device(struct eeh_dev *edev)
462 struct pci_driver *driver;
463 struct pci_dev *dev = eeh_dev_to_pci_dev(edev);
465 if (!(edev->physfn)) {
466 eeh_edev_warn(edev, "Not for VF\n");
470 driver = eeh_pcid_get(dev);
472 if (driver->err_handler) {
479 #ifdef CONFIG_PCI_IOV
480 pci_iov_add_virtfn(edev->physfn, edev->vf_index);
485 static void eeh_rmv_device(struct eeh_dev *edev, void *userdata)
487 struct pci_driver *driver;
488 struct pci_dev *dev = eeh_dev_to_pci_dev(edev);
489 struct eeh_rmv_data *rmv_data = (struct eeh_rmv_data *)userdata;
492 * Actually, we should remove the PCI bridges as well.
493 * However, that's lots of complexity to do that,
494 * particularly some of devices under the bridge might
495 * support EEH. So we just care about PCI devices for
498 if (!eeh_edev_actionable(edev) ||
499 (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE))
503 driver = eeh_pcid_get(dev);
505 if (driver->err_handler &&
506 driver->err_handler->error_detected &&
507 driver->err_handler->slot_reset) {
515 /* Remove it from PCI subsystem */
516 pr_info("EEH: Removing %s without EEH sensitive driver\n",
518 edev->mode |= EEH_DEV_DISCONNECTED;
520 rmv_data->removed_dev_count++;
523 #ifdef CONFIG_PCI_IOV
524 pci_iov_remove_virtfn(edev->physfn, edev->vf_index);
528 list_add(&edev->rmv_entry, &rmv_data->removed_vf_list);
530 pci_lock_rescan_remove();
531 pci_stop_and_remove_bus_device(dev);
532 pci_unlock_rescan_remove();
536 static void *eeh_pe_detach_dev(struct eeh_pe *pe, void *userdata)
538 struct eeh_dev *edev, *tmp;
540 eeh_pe_for_each_dev(pe, edev, tmp) {
541 if (!(edev->mode & EEH_DEV_DISCONNECTED))
544 edev->mode &= ~(EEH_DEV_DISCONNECTED | EEH_DEV_IRQ_DISABLED);
545 eeh_pe_tree_remove(edev);
552 * Explicitly clear PE's frozen state for PowerNV where
553 * we have frozen PE until BAR restore is completed. It's
554 * harmless to clear it for pSeries. To be consistent with
555 * PE reset (for 3 times), we try to clear the frozen state
556 * for 3 times as well.
558 static int eeh_clear_pe_frozen_state(struct eeh_pe *root, bool include_passed)
563 eeh_for_each_pe(root, pe) {
564 if (include_passed || !eeh_pe_passed(pe)) {
565 for (i = 0; i < 3; i++)
566 if (!eeh_unfreeze_pe(pe))
572 eeh_pe_state_clear(root, EEH_PE_ISOLATED, include_passed);
576 int eeh_pe_reset_and_recover(struct eeh_pe *pe)
580 /* Bail if the PE is being recovered */
581 if (pe->state & EEH_PE_RECOVERING)
584 /* Put the PE into recovery mode */
585 eeh_pe_state_mark(pe, EEH_PE_RECOVERING);
588 eeh_pe_dev_traverse(pe, eeh_dev_save_state, NULL);
591 ret = eeh_pe_reset_full(pe, true);
593 eeh_pe_state_clear(pe, EEH_PE_RECOVERING, true);
597 /* Unfreeze the PE */
598 ret = eeh_clear_pe_frozen_state(pe, true);
600 eeh_pe_state_clear(pe, EEH_PE_RECOVERING, true);
604 /* Restore device state */
605 eeh_pe_dev_traverse(pe, eeh_dev_restore_state, NULL);
607 /* Clear recovery mode */
608 eeh_pe_state_clear(pe, EEH_PE_RECOVERING, true);
614 * eeh_reset_device - Perform actual reset of a pci slot
615 * @driver_eeh_aware: Does the device's driver provide EEH support?
617 * @bus: PCI bus corresponding to the isolcated slot
618 * @rmv_data: Optional, list to record removed devices
620 * This routine must be called to do reset on the indicated PE.
621 * During the reset, udev might be invoked because those affected
622 * PCI devices will be removed and then added.
624 static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus,
625 struct eeh_rmv_data *rmv_data,
626 bool driver_eeh_aware)
630 struct eeh_dev *edev;
631 struct eeh_pe *tmp_pe;
632 bool any_passed = false;
634 eeh_for_each_pe(pe, tmp_pe)
635 any_passed |= eeh_pe_passed(tmp_pe);
637 /* pcibios will clear the counter; save the value */
638 cnt = pe->freeze_count;
642 * We don't remove the corresponding PE instances because
643 * we need the information afterwords. The attached EEH
644 * devices are expected to be attached soon when calling
645 * into pci_hp_add_devices().
647 eeh_pe_state_mark(pe, EEH_PE_KEEP);
648 if (any_passed || driver_eeh_aware || (pe->type & EEH_PE_VF)) {
649 eeh_pe_dev_traverse(pe, eeh_rmv_device, rmv_data);
651 pci_lock_rescan_remove();
652 pci_hp_remove_devices(bus);
653 pci_unlock_rescan_remove();
657 * Reset the pci controller. (Asserts RST#; resets config space).
658 * Reconfigure bridges and devices. Don't try to bring the system
659 * up if the reset failed for some reason.
661 * During the reset, it's very dangerous to have uncontrolled PCI
662 * config accesses. So we prefer to block them. However, controlled
663 * PCI config accesses initiated from EEH itself are allowed.
665 rc = eeh_pe_reset_full(pe, false);
669 pci_lock_rescan_remove();
672 eeh_ops->configure_bridge(pe);
673 eeh_pe_restore_bars(pe);
675 /* Clear frozen state */
676 rc = eeh_clear_pe_frozen_state(pe, false);
678 pci_unlock_rescan_remove();
682 /* Give the system 5 seconds to finish running the user-space
683 * hotplug shutdown scripts, e.g. ifdown for ethernet. Yes,
684 * this is a hack, but if we don't do this, and try to bring
685 * the device up before the scripts have taken it down,
686 * potentially weird things happen.
688 if (!driver_eeh_aware || rmv_data->removed_dev_count) {
689 pr_info("EEH: Sleep 5s ahead of %s hotplug\n",
690 (driver_eeh_aware ? "partial" : "complete"));
694 * The EEH device is still connected with its parent
695 * PE. We should disconnect it so the binding can be
696 * rebuilt when adding PCI devices.
698 edev = list_first_entry(&pe->edevs, struct eeh_dev, entry);
699 eeh_pe_traverse(pe, eeh_pe_detach_dev, NULL);
700 if (pe->type & EEH_PE_VF) {
701 eeh_add_virt_device(edev);
703 if (!driver_eeh_aware)
704 eeh_pe_state_clear(pe, EEH_PE_PRI_BUS, true);
705 pci_hp_add_devices(bus);
708 eeh_pe_state_clear(pe, EEH_PE_KEEP, true);
711 pe->freeze_count = cnt;
713 pci_unlock_rescan_remove();
717 /* The longest amount of time to wait for a pci device
718 * to come back on line, in seconds.
720 #define MAX_WAIT_FOR_RECOVERY 300
723 /* Walks the PE tree after processing an event to remove any stale PEs.
725 * NB: This needs to be recursive to ensure the leaf PEs get removed
726 * before their parents do. Although this is possible to do recursively
727 * we don't since this is easier to read and we need to garantee
728 * the leaf nodes will be handled first.
730 static void eeh_pe_cleanup(struct eeh_pe *pe)
732 struct eeh_pe *child_pe, *tmp;
734 list_for_each_entry_safe(child_pe, tmp, &pe->child_list, child)
735 eeh_pe_cleanup(child_pe);
737 if (pe->state & EEH_PE_KEEP)
740 if (!(pe->state & EEH_PE_INVALID))
743 if (list_empty(&pe->edevs) && list_empty(&pe->child_list)) {
744 list_del(&pe->child);
750 * eeh_check_slot_presence - Check if a device is still present in a slot
751 * @pdev: pci_dev to check
753 * This function may return a false positive if we can't determine the slot's
754 * presence state. This might happen for for PCIe slots if the PE containing
755 * the upstream bridge is also frozen, or the bridge is part of the same PE
758 * This shouldn't happen often, but you might see it if you hotplug a PCIe
761 static bool eeh_slot_presence_check(struct pci_dev *pdev)
763 const struct hotplug_slot_ops *ops;
764 struct pci_slot *slot;
771 if (pdev->error_state == pci_channel_io_perm_failure)
775 if (!slot || !slot->hotplug)
778 ops = slot->hotplug->ops;
779 if (!ops || !ops->get_adapter_status)
782 /* set the attention indicator while we've got the slot ops */
783 if (ops->set_attention_status)
784 ops->set_attention_status(slot->hotplug, 1);
786 rc = ops->get_adapter_status(slot->hotplug, &state);
793 static void eeh_clear_slot_attention(struct pci_dev *pdev)
795 const struct hotplug_slot_ops *ops;
796 struct pci_slot *slot;
801 if (pdev->error_state == pci_channel_io_perm_failure)
805 if (!slot || !slot->hotplug)
808 ops = slot->hotplug->ops;
809 if (!ops || !ops->set_attention_status)
812 ops->set_attention_status(slot->hotplug, 0);
816 * eeh_handle_normal_event - Handle EEH events on a specific PE
817 * @pe: EEH PE - which should not be used after we return, as it may
818 * have been invalidated.
820 * Attempts to recover the given PE. If recovery fails or the PE has failed
821 * too many times, remove the PE.
823 * While PHB detects address or data parity errors on particular PCI
824 * slot, the associated PE will be frozen. Besides, DMA's occurring
825 * to wild addresses (which usually happen due to bugs in device
826 * drivers or in PCI adapter firmware) can cause EEH error. #SERR,
827 * #PERR or other misc PCI-related errors also can trigger EEH errors.
829 * Recovery process consists of unplugging the device driver (which
830 * generated hotplug events to userspace), then issuing a PCI #RST to
831 * the device, then reconfiguring the PCI config space for all bridges
832 * & devices under this slot, and then finally restarting the device
833 * drivers (which cause a second set of hotplug events to go out to
836 void eeh_handle_normal_event(struct eeh_pe *pe)
839 struct eeh_dev *edev, *tmp;
840 struct eeh_pe *tmp_pe;
842 enum pci_ers_result result = PCI_ERS_RESULT_NONE;
843 struct eeh_rmv_data rmv_data =
844 {LIST_HEAD_INIT(rmv_data.removed_vf_list), 0};
847 bus = eeh_pe_bus_get(pe);
849 pr_err("%s: Cannot find PCI bus for PHB#%x-PE#%x\n",
850 __func__, pe->phb->global_number, pe->addr);
855 * When devices are hot-removed we might get an EEH due to
856 * a driver attempting to touch the MMIO space of a removed
857 * device. In this case we don't have a device to recover
858 * so suppress the event if we can't find any present devices.
860 * The hotplug driver should take care of tearing down the
863 eeh_for_each_pe(pe, tmp_pe)
864 eeh_pe_for_each_dev(tmp_pe, edev, tmp)
865 if (eeh_slot_presence_check(edev->pdev))
869 pr_debug("EEH: Frozen PHB#%x-PE#%x is empty!\n",
870 pe->phb->global_number, pe->addr);
871 goto out; /* nothing to recover */
875 if (pe->type & EEH_PE_PHB) {
876 pr_err("EEH: Recovering PHB#%x, location: %s\n",
877 pe->phb->global_number, eeh_pe_loc_get(pe));
879 struct eeh_pe *phb_pe = eeh_phb_pe_get(pe->phb);
881 pr_err("EEH: Recovering PHB#%x-PE#%x\n",
882 pe->phb->global_number, pe->addr);
883 pr_err("EEH: PE location: %s, PHB location: %s\n",
884 eeh_pe_loc_get(pe), eeh_pe_loc_get(phb_pe));
887 #ifdef CONFIG_STACKTRACE
889 * Print the saved stack trace now that we've verified there's
890 * something to recover.
892 if (pe->trace_entries) {
893 void **ptrs = (void **) pe->stack_trace;
896 pr_err("EEH: Frozen PHB#%x-PE#%x detected\n",
897 pe->phb->global_number, pe->addr);
899 /* FIXME: Use the same format as dump_stack() */
900 pr_err("EEH: Call Trace:\n");
901 for (i = 0; i < pe->trace_entries; i++)
902 pr_err("EEH: [%pK] %pS\n", ptrs[i], ptrs[i]);
904 pe->trace_entries = 0;
906 #endif /* CONFIG_STACKTRACE */
908 eeh_pe_update_time_stamp(pe);
910 if (pe->freeze_count > eeh_max_freezes) {
911 pr_err("EEH: PHB#%x-PE#%x has failed %d times in the last hour and has been permanently disabled.\n",
912 pe->phb->global_number, pe->addr,
914 result = PCI_ERS_RESULT_DISCONNECT;
917 eeh_for_each_pe(pe, tmp_pe)
918 eeh_pe_for_each_dev(tmp_pe, edev, tmp)
919 edev->mode &= ~EEH_DEV_NO_HANDLER;
921 /* Walk the various device drivers attached to this slot through
922 * a reset sequence, giving each an opportunity to do what it needs
923 * to accomplish the reset. Each child gets a report of the
924 * status ... if any child can't handle the reset, then the entire
925 * slot is dlpar removed and added.
927 * When the PHB is fenced, we have to issue a reset to recover from
928 * the error. Override the result if necessary to have partially
929 * hotplug for this case.
931 if (result != PCI_ERS_RESULT_DISCONNECT) {
932 pr_warn("EEH: This PCI device has failed %d times in the last hour and will be permanently disabled after %d failures.\n",
933 pe->freeze_count, eeh_max_freezes);
934 pr_info("EEH: Notify device drivers to shutdown\n");
935 eeh_set_channel_state(pe, pci_channel_io_frozen);
936 eeh_set_irq_state(pe, false);
937 eeh_pe_report("error_detected(IO frozen)", pe,
938 eeh_report_error, &result);
939 if ((pe->type & EEH_PE_PHB) &&
940 result != PCI_ERS_RESULT_NONE &&
941 result != PCI_ERS_RESULT_NEED_RESET)
942 result = PCI_ERS_RESULT_NEED_RESET;
945 /* Get the current PCI slot state. This can take a long time,
946 * sometimes over 300 seconds for certain systems.
948 if (result != PCI_ERS_RESULT_DISCONNECT) {
949 rc = eeh_wait_state(pe, MAX_WAIT_FOR_RECOVERY*1000);
950 if (rc < 0 || rc == EEH_STATE_NOT_SUPPORT) {
951 pr_warn("EEH: Permanent failure\n");
952 result = PCI_ERS_RESULT_DISCONNECT;
956 /* Since rtas may enable MMIO when posting the error log,
957 * don't post the error log until after all dev drivers
958 * have been informed.
960 if (result != PCI_ERS_RESULT_DISCONNECT) {
961 pr_info("EEH: Collect temporary log\n");
962 eeh_slot_error_detail(pe, EEH_LOG_TEMP);
965 /* If all device drivers were EEH-unaware, then shut
966 * down all of the device drivers, and hope they
967 * go down willingly, without panicing the system.
969 if (result == PCI_ERS_RESULT_NONE) {
970 pr_info("EEH: Reset with hotplug activity\n");
971 rc = eeh_reset_device(pe, bus, NULL, false);
973 pr_warn("%s: Unable to reset, err=%d\n",
975 result = PCI_ERS_RESULT_DISCONNECT;
979 /* If all devices reported they can proceed, then re-enable MMIO */
980 if (result == PCI_ERS_RESULT_CAN_RECOVER) {
981 pr_info("EEH: Enable I/O for affected devices\n");
982 rc = eeh_pci_enable(pe, EEH_OPT_THAW_MMIO);
985 result = PCI_ERS_RESULT_DISCONNECT;
987 result = PCI_ERS_RESULT_NEED_RESET;
989 pr_info("EEH: Notify device drivers to resume I/O\n");
990 eeh_pe_report("mmio_enabled", pe,
991 eeh_report_mmio_enabled, &result);
995 /* If all devices reported they can proceed, then re-enable DMA */
996 if (result == PCI_ERS_RESULT_CAN_RECOVER) {
997 pr_info("EEH: Enabled DMA for affected devices\n");
998 rc = eeh_pci_enable(pe, EEH_OPT_THAW_DMA);
1001 result = PCI_ERS_RESULT_DISCONNECT;
1003 result = PCI_ERS_RESULT_NEED_RESET;
1006 * We didn't do PE reset for the case. The PE
1007 * is still in frozen state. Clear it before
1010 eeh_pe_state_clear(pe, EEH_PE_ISOLATED, true);
1011 result = PCI_ERS_RESULT_RECOVERED;
1015 /* If any device called out for a reset, then reset the slot */
1016 if (result == PCI_ERS_RESULT_NEED_RESET) {
1017 pr_info("EEH: Reset without hotplug activity\n");
1018 rc = eeh_reset_device(pe, bus, &rmv_data, true);
1020 pr_warn("%s: Cannot reset, err=%d\n",
1022 result = PCI_ERS_RESULT_DISCONNECT;
1024 result = PCI_ERS_RESULT_NONE;
1025 eeh_set_channel_state(pe, pci_channel_io_normal);
1026 eeh_set_irq_state(pe, true);
1027 eeh_pe_report("slot_reset", pe, eeh_report_reset,
1032 if ((result == PCI_ERS_RESULT_RECOVERED) ||
1033 (result == PCI_ERS_RESULT_NONE)) {
1035 * For those hot removed VFs, we should add back them after PF
1036 * get recovered properly.
1038 list_for_each_entry_safe(edev, tmp, &rmv_data.removed_vf_list,
1040 eeh_add_virt_device(edev);
1041 list_del(&edev->rmv_entry);
1044 /* Tell all device drivers that they can resume operations */
1045 pr_info("EEH: Notify device driver to resume\n");
1046 eeh_set_channel_state(pe, pci_channel_io_normal);
1047 eeh_set_irq_state(pe, true);
1048 eeh_pe_report("resume", pe, eeh_report_resume, NULL);
1049 eeh_for_each_pe(pe, tmp_pe) {
1050 eeh_pe_for_each_dev(tmp_pe, edev, tmp) {
1051 edev->mode &= ~EEH_DEV_NO_HANDLER;
1052 edev->in_error = false;
1056 pr_info("EEH: Recovery successful.\n");
1061 * About 90% of all real-life EEH failures in the field
1062 * are due to poorly seated PCI cards. Only 10% or so are
1063 * due to actual, failed cards.
1065 pr_err("EEH: Unable to recover from failure from PHB#%x-PE#%x.\n"
1066 "Please try reseating or replacing it\n",
1067 pe->phb->global_number, pe->addr);
1069 eeh_slot_error_detail(pe, EEH_LOG_PERM);
1071 /* Notify all devices that they're about to go down. */
1072 eeh_set_irq_state(pe, false);
1073 eeh_pe_report("error_detected(permanent failure)", pe,
1074 eeh_report_failure, NULL);
1075 eeh_set_channel_state(pe, pci_channel_io_perm_failure);
1077 /* Mark the PE to be removed permanently */
1078 eeh_pe_state_mark(pe, EEH_PE_REMOVED);
1081 * Shut down the device drivers for good. We mark
1082 * all removed devices correctly to avoid access
1083 * the their PCI config any more.
1085 if (pe->type & EEH_PE_VF) {
1086 eeh_pe_dev_traverse(pe, eeh_rmv_device, NULL);
1087 eeh_pe_dev_mode_mark(pe, EEH_DEV_REMOVED);
1089 eeh_pe_state_clear(pe, EEH_PE_PRI_BUS, true);
1090 eeh_pe_dev_mode_mark(pe, EEH_DEV_REMOVED);
1092 pci_lock_rescan_remove();
1093 pci_hp_remove_devices(bus);
1094 pci_unlock_rescan_remove();
1095 /* The passed PE should no longer be used */
1101 * Clean up any PEs without devices. While marked as EEH_PE_RECOVERYING
1102 * we don't want to modify the PE tree structure so we do it here.
1106 /* clear the slot attention LED for all recovered devices */
1107 eeh_for_each_pe(pe, tmp_pe)
1108 eeh_pe_for_each_dev(tmp_pe, edev, tmp)
1109 eeh_clear_slot_attention(edev->pdev);
1111 eeh_pe_state_clear(pe, EEH_PE_RECOVERING, true);
1115 * eeh_handle_special_event - Handle EEH events without a specific failing PE
1117 * Called when an EEH event is detected but can't be narrowed down to a
1118 * specific PE. Iterates through possible failures and handles them as
1121 void eeh_handle_special_event(void)
1123 struct eeh_pe *pe, *phb_pe, *tmp_pe;
1124 struct eeh_dev *edev, *tmp_edev;
1125 struct pci_bus *bus;
1126 struct pci_controller *hose;
1127 unsigned long flags;
1132 rc = eeh_ops->next_error(&pe);
1135 case EEH_NEXT_ERR_DEAD_IOC:
1136 /* Mark all PHBs in dead state */
1137 eeh_serialize_lock(&flags);
1139 /* Purge all events */
1140 eeh_remove_event(NULL, true);
1142 list_for_each_entry(hose, &hose_list, list_node) {
1143 phb_pe = eeh_phb_pe_get(hose);
1144 if (!phb_pe) continue;
1146 eeh_pe_mark_isolated(phb_pe);
1149 eeh_serialize_unlock(flags);
1152 case EEH_NEXT_ERR_FROZEN_PE:
1153 case EEH_NEXT_ERR_FENCED_PHB:
1154 case EEH_NEXT_ERR_DEAD_PHB:
1155 /* Mark the PE in fenced state */
1156 eeh_serialize_lock(&flags);
1158 /* Purge all events of the PHB */
1159 eeh_remove_event(pe, true);
1161 if (rc != EEH_NEXT_ERR_DEAD_PHB)
1162 eeh_pe_state_mark(pe, EEH_PE_RECOVERING);
1163 eeh_pe_mark_isolated(pe);
1165 eeh_serialize_unlock(flags);
1168 case EEH_NEXT_ERR_NONE:
1171 pr_warn("%s: Invalid value %d from next_error()\n",
1177 * For fenced PHB and frozen PE, it's handled as normal
1178 * event. We have to remove the affected PHBs for dead
1181 if (rc == EEH_NEXT_ERR_FROZEN_PE ||
1182 rc == EEH_NEXT_ERR_FENCED_PHB) {
1183 eeh_pe_state_mark(pe, EEH_PE_RECOVERING);
1184 eeh_handle_normal_event(pe);
1186 eeh_for_each_pe(pe, tmp_pe)
1187 eeh_pe_for_each_dev(tmp_pe, edev, tmp_edev)
1188 edev->mode &= ~EEH_DEV_NO_HANDLER;
1190 /* Notify all devices to be down */
1191 eeh_pe_state_clear(pe, EEH_PE_PRI_BUS, true);
1193 "error_detected(permanent failure)", pe,
1194 eeh_report_failure, NULL);
1195 eeh_set_channel_state(pe, pci_channel_io_perm_failure);
1197 pci_lock_rescan_remove();
1198 list_for_each_entry(hose, &hose_list, list_node) {
1199 phb_pe = eeh_phb_pe_get(hose);
1201 !(phb_pe->state & EEH_PE_ISOLATED) ||
1202 (phb_pe->state & EEH_PE_RECOVERING))
1205 bus = eeh_pe_bus_get(phb_pe);
1207 pr_err("%s: Cannot find PCI bus for "
1210 pe->phb->global_number,
1214 pci_hp_remove_devices(bus);
1216 pci_unlock_rescan_remove();
1220 * If we have detected dead IOC, we needn't proceed
1221 * any more since all PHBs would have been removed
1223 if (rc == EEH_NEXT_ERR_DEAD_IOC)
1225 } while (rc != EEH_NEXT_ERR_NONE);