创建自定义模块后，setup:upgrade命令后报错

执行命令报错

alian@DESKTOP-KL4FE27:~/Sites/magento$ bin/magento setup:upgrade
Warning: DOMXPath::query(): Invalid expression in /var/www/html/vendor/magento/framework/Config/Dom.php on line 337
alian@DESKTOP-KL4FE27:~/Sites/magento$ bin/root chmod -R 777 ./var
alian@DESKTOP-KL4FE27:~/Sites/magento$ bin/magento setup:upgrade
Warning: DOMXPath::query(): Invalid expression in /var/www/html/vendor/magento/framework/Config/Dom.php on line 337

我都是按官方教程来的。
我的版本是2.4.3
大佬看到麻烦指导下