virtio: console: Generate a kobject CHANGE event on adding 'name' attribute

When the host lets us know what 'name' a port is assigned, we create the
sysfs 'name' attribute. Generate a 'change' event after this so that
udev wakes up and acts on the rules for virtio-ports (currently there's
only one rule that creates a symlink from the 'name' to the actual char
device).
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

drivers/char/virtio_console.c

@@ -947,11 +947,18 @@ static void handle_control_message(struct ports_device *portdev,
 		 */
 		err = sysfs_create_group(&port->dev->kobj,
 					 &port_attribute_group);
-		if (err)
+		if (err) {
 			dev_err(port->dev,
 				"Error %d creating sysfs device attributes\n",
 				err);
-
+		} else {
+			/*
+			 * Generate a udev event so that appropriate
+			 * symlinks can be created based on udev
+			 * rules.
+			 */
+			kobject_uevent(&port->dev->kobj, KOBJ_CHANGE);
+		}
 		break;
 	case VIRTIO_CONSOLE_PORT_REMOVE:
 		/*