[PATCH 16/16][BUG] PCI hotplug core: add missing lock for hotplug slot list (Not for mainline!)

[Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>]

Add missing lock for manipulating pci_hotplug_slot_list.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>

---
 drivers/pci/hotplug/pci_hotplug_core.c |   13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

Index: linux-2.6.25-rc6/drivers/pci/hotplug/pci_hotplug_core.c
===================================================================
--- linux-2.6.25-rc6.orig/drivers/pci/hotplug/pci_hotplug_core.c
+++ linux-2.6.25-rc6/drivers/pci/hotplug/pci_hotplug_core.c
@@ -61,6 +61,7 @@ static int debug;
 //////////////////////////////////////////////////////////////////
 
 static LIST_HEAD(pci_hotplug_slot_list);
+static DEFINE_SPINLOCK(pci_hotplug_slot_list_lock);
 
 /* these strings match up with the values in pci_bus_speed */
 static char *pci_bus_speed_strings[] = {
@@ -529,12 +530,16 @@ static struct hotplug_slot *get_slot_fro
 	struct hotplug_slot *slot;
 	struct list_head *tmp;
 
+	spin_lock(&pci_hotplug_slot_list_lock);
 	list_for_each (tmp, &pci_hotplug_slot_list) {
 		slot = list_entry (tmp, struct hotplug_slot, slot_list);
 		if (strcmp(slot->name, name) == 0)
-			return slot;
+			goto out;
 	}
-	return NULL;
+	slot = NULL;
+out:
+	spin_unlock(&pci_hotplug_slot_list_lock);
+	return slot;
 }
 
 /**
@@ -584,7 +589,9 @@ int pci_hp_register(struct hotplug_slot 
 		}
 	}
 
+	spin_lock(&pci_hotplug_slot_list_lock);
 	list_add(&slot->slot_list, &pci_hotplug_slot_list);
+	spin_unlock(&pci_hotplug_slot_list_lock);
 
 	result = fs_add_slot(pci_slot);
 	kobject_uevent(&pci_slot->kobj, KOBJ_ADD);
@@ -613,7 +620,9 @@ int pci_hp_deregister(struct hotplug_slo
 	if (temp != hotplug)
 		return -ENODEV;
 
+	spin_lock(&pci_hotplug_slot_list_lock);
 	list_del(&hotplug->slot_list);
+	spin_unlock(&pci_hotplug_slot_list_lock);
 
 	slot = hotplug->pci_slot;
 	fs_remove_slot(slot);