--- y/drivers/usb/gadget/udc/core.c
+++ c/drivers/usb/gadget/udc/core.c
@@ -1722,10 +1722,11 @@ static int usb_udc_uevent(struct device
 	struct usb_udc		*udc = container_of(dev, struct usb_udc, dev);
 	int			ret;
 
+	mutex_lock(&udc_lock);
 	ret = add_uevent_var(env, "USB_UDC_NAME=%s", udc->gadget->name);
 	if (ret) {
 		dev_err(dev, "failed to add uevent USB_UDC_NAME\n");
-		return ret;
+		goto out;
 	}
 
 	if (udc->driver) {
@@ -1733,11 +1734,12 @@ static int usb_udc_uevent(struct device
 				udc->driver->function);
 		if (ret) {
 			dev_err(dev, "failed to add uevent USB_UDC_DRIVER\n");
-			return ret;
 		}
 	}
 
-	return 0;
+out:
+	mutex_unlock(&udc_lock);
+	return ret;
 }
 
 static struct bus_type gadget_bus_type = {