1 files changed, 95 insertions, 110 deletions

diff --git a/arch/powerpc/kernel/eeh_driver.c b/arch/powerpc/kernel/eeh_driver.c
index 0c0b66fc5bfb..b8a329f04814 100644
--- a/arch/powerpc/kernel/eeh_driver.c
+++ b/arch/powerpc/kernel/eeh_driver.c
@@ -207,18 +207,18 @@ static void *eeh_report_error(void *data, void *userdata)
 
 	if (!dev || eeh_dev_removed(edev) || eeh_pe_passed(edev->pe))
 		return NULL;
+
+	device_lock(&dev->dev);
 	dev->error_state = pci_channel_io_frozen;
 
 	driver = eeh_pcid_get(dev);
-	if (!driver) return NULL;
+	if (!driver) goto out_no_dev;
 
 	eeh_disable_irq(dev);
 
 	if (!driver->err_handler ||
-	    !driver->err_handler->error_detected) {
-		eeh_pcid_put(dev);
-		return NULL;
-	}
+	    !driver->err_handler->error_detected)
+		goto out;
 
 	rc = driver->err_handler->error_detected(dev, pci_channel_io_frozen);
 
@@ -227,8 +227,12 @@ static void *eeh_report_error(void *data, void *userdata)
 	if (*res == PCI_ERS_RESULT_NONE) *res = rc;
 
 	edev->in_error = true;
-	eeh_pcid_put(dev);
 	pci_uevent_ers(dev, PCI_ERS_RESULT_NONE);
+
+out:
+	eeh_pcid_put(dev);
+out_no_dev:
+	device_unlock(&dev->dev);
 	return NULL;
 }
 
@@ -251,15 +255,14 @@ static void *eeh_report_mmio_enabled(void *data, void *userdata)
 	if (!dev || eeh_dev_removed(edev) || eeh_pe_passed(edev->pe))
 		return NULL;
 
+	device_lock(&dev->dev);
 	driver = eeh_pcid_get(dev);
-	if (!driver) return NULL;
+	if (!driver) goto out_no_dev;
 
 	if (!driver->err_handler ||
 	    !driver->err_handler->mmio_enabled ||
-	    (edev->mode & EEH_DEV_NO_HANDLER)) {
-		eeh_pcid_put(dev);
-		return NULL;
-	}
+	    (edev->mode & EEH_DEV_NO_HANDLER))
+		goto out;
 
 	rc = driver->err_handler->mmio_enabled(dev);
 
@@ -267,7 +270,10 @@ static void *eeh_report_mmio_enabled(void *data, void *userdata)
 	if (rc == PCI_ERS_RESULT_NEED_RESET) *res = rc;
 	if (*res == PCI_ERS_RESULT_NONE) *res = rc;
 
+out:
 	eeh_pcid_put(dev);
+out_no_dev:
+	device_unlock(&dev->dev);
 	return NULL;
 }
 
@@ -290,20 +296,20 @@ static void *eeh_report_reset(void *data, void *userdata)
 
 	if (!dev || eeh_dev_removed(edev) || eeh_pe_passed(edev->pe))
 		return NULL;
+
+	device_lock(&dev->dev);
 	dev->error_state = pci_channel_io_normal;
 
 	driver = eeh_pcid_get(dev);
-	if (!driver) return NULL;
+	if (!driver) goto out_no_dev;
 
 	eeh_enable_irq(dev);
 
 	if (!driver->err_handler ||
 	    !driver->err_handler->slot_reset ||
 	    (edev->mode & EEH_DEV_NO_HANDLER) ||
-	    (!edev->in_error)) {
-		eeh_pcid_put(dev);
-		return NULL;
-	}
+	    (!edev->in_error))
+		goto out;
 
 	rc = driver->err_handler->slot_reset(dev);
 	if ((*res == PCI_ERS_RESULT_NONE) ||
@@ -311,7 +317,10 @@ static void *eeh_report_reset(void *data, void *userdata)
 	if (*res == PCI_ERS_RESULT_DISCONNECT &&
 	     rc == PCI_ERS_RESULT_NEED_RESET) *res = rc;
 
+out:
 	eeh_pcid_put(dev);
+out_no_dev:
+	device_unlock(&dev->dev);
 	return NULL;
 }
 
@@ -362,10 +371,12 @@ static void *eeh_report_resume(void *data, void *userdata)
 
 	if (!dev || eeh_dev_removed(edev) || eeh_pe_passed(edev->pe))
 		return NULL;
+
+	device_lock(&dev->dev);
 	dev->error_state = pci_channel_io_normal;
 
 	driver = eeh_pcid_get(dev);
-	if (!driver) return NULL;
+	if (!driver) goto out_no_dev;
 
 	was_in_error = edev->in_error;
 	edev->in_error = false;
@@ -375,18 +386,20 @@ static void *eeh_report_resume(void *data, void *userdata)
 	    !driver->err_handler->resume ||
 	    (edev->mode & EEH_DEV_NO_HANDLER) || !was_in_error) {
 		edev->mode &= ~EEH_DEV_NO_HANDLER;
-		eeh_pcid_put(dev);
-		return NULL;
+		goto out;
 	}
 
 	driver->err_handler->resume(dev);
 
-	eeh_pcid_put(dev);
 	pci_uevent_ers(dev, PCI_ERS_RESULT_RECOVERED);
+out:
+	eeh_pcid_put(dev);
 #ifdef CONFIG_PCI_IOV
 	if (eeh_ops->notify_resume && eeh_dev_to_pdn(edev))
 		eeh_ops->notify_resume(eeh_dev_to_pdn(edev));
 #endif
+out_no_dev:
+	device_unlock(&dev->dev);
 	return NULL;
 }
 
@@ -406,23 +419,26 @@ static void *eeh_report_failure(void *data, void *userdata)
 
 	if (!dev || eeh_dev_removed(edev) || eeh_pe_passed(edev->pe))
 		return NULL;
+
+	device_lock(&dev->dev);
 	dev->error_state = pci_channel_io_perm_failure;
 
 	driver = eeh_pcid_get(dev);
-	if (!driver) return NULL;
+	if (!driver) goto out_no_dev;
 
 	eeh_disable_irq(dev);
 
 	if (!driver->err_handler ||
-	    !driver->err_handler->error_detected) {
-		eeh_pcid_put(dev);
-		return NULL;
-	}
+	    !driver->err_handler->error_detected)
+		goto out;
 
 	driver->err_handler->error_detected(dev, pci_channel_io_perm_failure);
 
-	eeh_pcid_put(dev);
 	pci_uevent_ers(dev, PCI_ERS_RESULT_DISCONNECT);
+out:
+	eeh_pcid_put(dev);
+out_no_dev:
+	device_unlock(&dev->dev);
 	return NULL;
 }
 
@@ -619,17 +635,19 @@ int eeh_pe_reset_and_recover(struct eeh_pe *pe)
 
 /**
  * eeh_reset_device - Perform actual reset of a pci slot
+ * @driver_eeh_aware: Does the device's driver provide EEH support?
  * @pe: EEH PE
  * @bus: PCI bus corresponding to the isolcated slot
+ * @rmv_data: Optional, list to record removed devices
  *
  * This routine must be called to do reset on the indicated PE.
  * During the reset, udev might be invoked because those affected
  * PCI devices will be removed and then added.
  */
 static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus,
-				struct eeh_rmv_data *rmv_data)
+			    struct eeh_rmv_data *rmv_data,
+			    bool driver_eeh_aware)
 {
-	struct pci_bus *frozen_bus = eeh_pe_bus_get(pe);
 	time64_t tstamp;
 	int cnt, rc;
 	struct eeh_dev *edev;
@@ -645,16 +663,12 @@ static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus,
 	 * into pci_hp_add_devices().
 	 */
 	eeh_pe_state_mark(pe, EEH_PE_KEEP);
-	if (bus) {
-		if (pe->type & EEH_PE_VF) {
-			eeh_pe_dev_traverse(pe, eeh_rmv_device, NULL);
-		} else {
-			pci_lock_rescan_remove();
-			pci_hp_remove_devices(bus);
-			pci_unlock_rescan_remove();
-		}
-	} else if (frozen_bus) {
+	if (driver_eeh_aware || (pe->type & EEH_PE_VF)) {
 		eeh_pe_dev_traverse(pe, eeh_rmv_device, rmv_data);
+	} else {
+		pci_lock_rescan_remove();
+		pci_hp_remove_devices(bus);
+		pci_unlock_rescan_remove();
 	}
 
 	/*
@@ -689,8 +703,9 @@ static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus,
 	 * the device up before the scripts have taken it down,
 	 * potentially weird things happen.
 	 */
-	if (bus) {
-		pr_info("EEH: Sleep 5s ahead of complete hotplug\n");
+	if (!driver_eeh_aware || rmv_data->removed) {
+		pr_info("EEH: Sleep 5s ahead of %s hotplug\n",
+			(driver_eeh_aware ? "partial" : "complete"));
 		ssleep(5);
 
 		/*
@@ -703,19 +718,10 @@ static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus,
 		if (pe->type & EEH_PE_VF) {
 			eeh_add_virt_device(edev, NULL);
 		} else {
-			eeh_pe_state_clear(pe, EEH_PE_PRI_BUS);
+			if (!driver_eeh_aware)
+				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);
-
-		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)
-			eeh_add_virt_device(edev, NULL);
-		else
-			pci_hp_add_devices(frozen_bus);
 	}
 	eeh_pe_state_clear(pe, EEH_PE_KEEP);
 
@@ -733,28 +739,42 @@ static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus,
 
 /**
  * eeh_handle_normal_event - Handle EEH events on a specific PE
- * @pe: EEH PE
+ * @pe: EEH PE - which should not be used after we return, as it may
+ * have been invalidated.
  *
  * Attempts to recover the given PE.  If recovery fails or the PE has failed
  * too many times, remove the PE.
  *
- * Returns true if @pe should no longer be used, else false.
+ * While PHB detects address or data parity errors on particular PCI
+ * slot, the associated PE will be frozen. Besides, DMA's occurring
+ * to wild addresses (which usually happen due to bugs in device
+ * drivers or in PCI adapter firmware) can cause EEH error. #SERR,
+ * #PERR or other misc PCI-related errors also can trigger EEH errors.
+ *
+ * Recovery process consists of unplugging the device driver (which
+ * generated hotplug events to userspace), then issuing a PCI #RST to
+ * the device, then reconfiguring the PCI config space for all bridges
+ * & devices under this slot, and then finally restarting the device
+ * drivers (which cause a second set of hotplug events to go out to
+ * userspace).
  */
-static bool eeh_handle_normal_event(struct eeh_pe *pe)
+void eeh_handle_normal_event(struct eeh_pe *pe)
 {
-	struct pci_bus *frozen_bus;
+	struct pci_bus *bus;
 	struct eeh_dev *edev, *tmp;
 	int rc = 0;
 	enum pci_ers_result result = PCI_ERS_RESULT_NONE;
 	struct eeh_rmv_data rmv_data = {LIST_HEAD_INIT(rmv_data.edev_list), 0};
 
-	frozen_bus = eeh_pe_bus_get(pe);
-	if (!frozen_bus) {
+	bus = eeh_pe_bus_get(pe);
+	if (!bus) {
 		pr_err("%s: Cannot find PCI bus for PHB#%x-PE#%x\n",
 			__func__, pe->phb->global_number, pe->addr);
-		return false;
+		return;
 	}
 
+	eeh_pe_state_mark(pe, EEH_PE_RECOVERING);
+
 	eeh_pe_update_time_stamp(pe);
 	pe->freeze_count++;
 	if (pe->freeze_count > eeh_max_freezes) {
@@ -806,7 +826,7 @@ static bool eeh_handle_normal_event(struct eeh_pe *pe)
 	 */
 	if (result == PCI_ERS_RESULT_NONE) {
 		pr_info("EEH: Reset with hotplug activity\n");
-		rc = eeh_reset_device(pe, frozen_bus, NULL);
+		rc = eeh_reset_device(pe, bus, NULL, false);
 		if (rc) {
 			pr_warn("%s: Unable to reset, err=%d\n",
 				__func__, rc);
@@ -858,7 +878,7 @@ static bool eeh_handle_normal_event(struct eeh_pe *pe)
 	/* If any device called out for a reset, then reset the slot */
 	if (result == PCI_ERS_RESULT_NEED_RESET) {
 		pr_info("EEH: Reset without hotplug activity\n");
-		rc = eeh_reset_device(pe, NULL, &rmv_data);
+		rc = eeh_reset_device(pe, bus, &rmv_data, true);
 		if (rc) {
 			pr_warn("%s: Cannot reset, err=%d\n",
 				__func__, rc);
@@ -891,7 +911,7 @@ static bool eeh_handle_normal_event(struct eeh_pe *pe)
 	pr_info("EEH: Notify device driver to resume\n");
 	eeh_pe_dev_traverse(pe, eeh_report_resume, NULL);
 
-	return false;
+	goto final;
 
 hard_fail:
 	/*
@@ -916,23 +936,21 @@ hard_fail:
 	 * all removed devices correctly to avoid access
 	 * the their PCI config any more.
 	 */
-	if (frozen_bus) {
-		if (pe->type & EEH_PE_VF) {
-			eeh_pe_dev_traverse(pe, eeh_rmv_device, NULL);
-			eeh_pe_dev_mode_mark(pe, EEH_DEV_REMOVED);
-		} else {
-			eeh_pe_state_clear(pe, EEH_PE_PRI_BUS);
-			eeh_pe_dev_mode_mark(pe, EEH_DEV_REMOVED);
-
-			pci_lock_rescan_remove();
-			pci_hp_remove_devices(frozen_bus);
-			pci_unlock_rescan_remove();
+	if (pe->type & EEH_PE_VF) {
+		eeh_pe_dev_traverse(pe, eeh_rmv_device, NULL);
+		eeh_pe_dev_mode_mark(pe, EEH_DEV_REMOVED);
+	} else {
+		eeh_pe_state_clear(pe, EEH_PE_PRI_BUS);
+		eeh_pe_dev_mode_mark(pe, EEH_DEV_REMOVED);
 
-			/* The passed PE should no longer be used */
-			return true;
-		}
+		pci_lock_rescan_remove();
+		pci_hp_remove_devices(bus);
+		pci_unlock_rescan_remove();
+		/* The passed PE should no longer be used */
+		return;
 	}
-	return false;
+final:
+	eeh_pe_state_clear(pe, EEH_PE_RECOVERING);
 }
 
 /**
@@ -942,7 +960,7 @@ hard_fail:
  * specific PE.  Iterates through possible failures and handles them as
  * necessary.
  */
-static void eeh_handle_special_event(void)
+void eeh_handle_special_event(void)
 {
 	struct eeh_pe *pe, *phb_pe;
 	struct pci_bus *bus;
@@ -1005,15 +1023,7 @@ static void eeh_handle_special_event(void)
 		 */
 		if (rc == EEH_NEXT_ERR_FROZEN_PE ||
 		    rc == EEH_NEXT_ERR_FENCED_PHB) {
-			/*
-			 * eeh_handle_normal_event() can make the PE stale if it
-			 * determines that the PE cannot possibly be recovered.
-			 * Don't modify the PE state if that's the case.
-			 */
-			if (eeh_handle_normal_event(pe))
-				continue;
-
-			eeh_pe_state_clear(pe, EEH_PE_RECOVERING);
+			eeh_handle_normal_event(pe);
 		} else {
 			pci_lock_rescan_remove();
 			list_for_each_entry(hose, &hose_list, list_node) {
@@ -1049,28 +1059,3 @@ static void eeh_handle_special_event(void)
 			break;
 	} while (rc != EEH_NEXT_ERR_NONE);
 }
-
-/**
- * eeh_handle_event - Reset a PCI device after hard lockup.
- * @pe: EEH PE
- *
- * While PHB detects address or data parity errors on particular PCI
- * slot, the associated PE will be frozen. Besides, DMA's occurring
- * to wild addresses (which usually happen due to bugs in device
- * drivers or in PCI adapter firmware) can cause EEH error. #SERR,
- * #PERR or other misc PCI-related errors also can trigger EEH errors.
- *
- * Recovery process consists of unplugging the device driver (which
- * generated hotplug events to userspace), then issuing a PCI #RST to
- * the device, then reconfiguring the PCI config space for all bridges
- * & devices under this slot, and then finally restarting the device
- * drivers (which cause a second set of hotplug events to go out to
- * userspace).
- */
-void eeh_handle_event(struct eeh_pe *pe)
-{
-	if (pe)
-		eeh_handle_normal_event(pe);
-	else
-		eeh_handle_special_event();
-}