Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6

* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6:
Driver Core: do not oops when driver_unregister() is called for unregistered drivers
sysfs: file.c: use create_singlethread_workqueue()

drivers/base/bus.c

···
 	}
 
 	kobject_uevent(&priv->kobj, KOBJ_ADD);
-	return error;
+	return 0;
 out_unregister:
+	kfree(drv->p);
+	drv->p = NULL;
 	kobject_put(&priv->kobj);
 out_put_bus:
 	bus_put(bus);

drivers/base/core.c

···
 	}
 
 	if (!dev_name(dev))
-		goto done;
+		goto name_error;
 
 	pr_debug("device: '%s': %s\n", dev_name(dev), __func__);
 
···
 	cleanup_device_parent(dev);
 	if (parent)
 		put_device(parent);
+name_error:
+	kfree(dev->p);
+	dev->p = NULL;
 	goto done;
 }
 

drivers/base/driver.c

···
  */
 void driver_unregister(struct device_driver *drv)
 {
+	if (!drv || !drv->p) {
+		WARN(1, "Unexpected driver unregister!\n");
+		return;
+	}
 	driver_remove_groups(drv, drv->groups);
 	bus_remove_driver(drv);
 }

fs/sysfs/file.c

···
 	mutex_unlock(&sysfs_workq_mutex);
 
 	if (sysfs_workqueue == NULL) {
-		sysfs_workqueue = create_workqueue("sysfsd");
+		sysfs_workqueue = create_singlethread_workqueue("sysfsd");
 		if (sysfs_workqueue == NULL) {
 			module_put(owner);
 			return -ENOMEM;