PCI: pciehp: Handle interrupts that happen during initialization.

Move the enabling of interrupts after all of the data structures
are setup so that we can safely run the interrupt handler as
soon as it is registered.
Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Tested-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: Jesse Barnes <jbarnes@hobbes.lan>

drivers/pci/hotplug/pciehp.h

@@ -111,6 +111,7 @@ struct controller {
 	int cmd_busy;
 	unsigned int no_cmd_complete:1;
 	unsigned int link_active_reporting:1;
+	unsigned int notification_enabled:1;
 };
 
 #define INT_BUTTON_IGNORE		0
@@ -170,6 +171,7 @@ extern int pciehp_configure_device(struct slot *p_slot);
 extern int pciehp_unconfigure_device(struct slot *p_slot);
 extern void pciehp_queue_pushbutton_work(struct work_struct *work);
 struct controller *pcie_init(struct pcie_device *dev);
+int pcie_init_notification(struct controller *ctrl);
 int pciehp_enable_slot(struct slot *p_slot);
 int pciehp_disable_slot(struct slot *p_slot);
 int pcie_enable_notification(struct controller *ctrl);

drivers/pci/hotplug/pciehp_core.c

@@ -434,6 +434,13 @@ static int pciehp_probe(struct pcie_device *dev, const struct pcie_port_service_
 		goto err_out_release_ctlr;
 	}
 
+	/* Enable events after we have setup the data structures */
+	rc = pcie_init_notification(ctrl);
+	if (rc) {
+		ctrl_err(ctrl, "Notification initialization failed\n");
+		goto err_out_release_ctlr;
+	}
+
 	/* Check if slot is occupied */
 	t_slot = pciehp_find_slot(ctrl, ctrl->slot_device_offset);
 	t_slot->hpc_ops->get_adapter_status(t_slot, &value);

drivers/pci/hotplug/pciehp_hpc.c

@@ -934,7 +934,7 @@ static void pcie_disable_notification(struct controller *ctrl)
 		ctrl_warn(ctrl, "Cannot disable software notification\n");
 }
 
-static int pcie_init_notification(struct controller *ctrl)
+int pcie_init_notification(struct controller *ctrl)
 {
 	if (pciehp_request_irq(ctrl))
 		return -1;
@@ -942,13 +942,17 @@ static int pcie_init_notification(struct controller *ctrl)
 		pciehp_free_irq(ctrl);
 		return -1;
 	}
+	ctrl->notification_enabled = 1;
 	return 0;
 }
 
 static void pcie_shutdown_notification(struct controller *ctrl)
 {
-	pcie_disable_notification(ctrl);
-	pciehp_free_irq(ctrl);
+	if (ctrl->notification_enabled) {
+		pcie_disable_notification(ctrl);
+		pciehp_free_irq(ctrl);
+		ctrl->notification_enabled = 0;
+	}
 }
 
 static int pcie_init_slot(struct controller *ctrl)
@@ -1110,13 +1114,8 @@ struct controller *pcie_init(struct pcie_device *dev)
 	if (pcie_init_slot(ctrl))
 		goto abort_ctrl;
 
-	if (pcie_init_notification(ctrl))
-		goto abort_slot;
-
 	return ctrl;
 
-abort_slot:
-	pcie_cleanup_slot(ctrl);
 abort_ctrl:
 	kfree(ctrl);
 abort: