Comment 0 for bug 1258043

即将安装完成时，出现GRUB相关报错弹框，点击确定后还是会出现安装完成需要重启的弹框，只是grub有问题，进不了安装好系统。

相关日志信息：
debconf: DbDriver "passwords" warning: could not open /var/cache/debconf/passwords.dat: 权限不够
Exception caught in process_line:
Traceback (most recent call last):
  File "/usr/lib/ubiquity/ubiquity/filteredcommand.py", line 145, in process_line
    return self.dbfilter.process_line()
  File "/usr/lib/ubiquity/ubiquity/debconffilter.py", line 430, in process_line
    data = self.db.command(command, *params)
  File "/usr/lib/python3/dist-packages/debconf.py", line 66, in command
    self.write.write("%s %s\n" % (command, ' '.join(map(str, params))))
ValueError: I/O operation on closed file.