无法处理 /proc/version_signature

Question

我启动了一个 docker 容器，然后在容器中安装了 ubuntu-advantage-tools，尽管在安装过程中出现了以下错误消息，但我认为这并不重要。

debconf: unable to initialize frontend: Dialog
debconf: (No usable dialog-like program is installed, so the dialog based frontend cannot be used. at /usr/share/perl5/Debconf/FrontEnd/Dialog.pm line 78.)
debconf: falling back to frontend: Readline
debconf: unable to initialize frontend: Readline
debconf: (Can't locate Term/ReadLine.pm in @INC (you may need to install the Term::ReadLine module) (@INC contains: /etc/perl /usr/local/lib/x86_64-linux-gnu/perl/5.34.0 /usr/local/share/perl/5.34.0 /usr/lib/x86_64-linux-gnu/perl5/5.34 /usr/share/perl5 /usr/lib/x86_64-linux-gnu/perl-base /usr/lib/x86_64-linux-gnu/perl/5.34 /usr/share/perl/5.34 /usr/local/lib/site_perl) at /usr/share/perl5/Debconf/FrontEnd/Readline.pm line 7.)
debconf: falling back to frontend: Teletype

之后，我可以正确运行以下命令：

# pro --version
27.11.2~22.04.1

# uname -a
Linux c67b17708016 4.12.14-120-default #1 SMP Thu Nov 7 16:39:09 UTC 2019 (fd9dc36) x86_64 x86_64 x86_64 GNU/Linux

# dpkg -l | grep advantage
ii  ubuntu-advantage-tools      27.11.2~22.04.1                         amd64        management tools for Ubuntu Advantage

# lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 22.04.1 LTS
Release:        22.04
Codename:       jammy
root@c67b17708016:/# cat /etc/os-release
PRETTY_NAME="Ubuntu 22.04.1 LTS"
NAME="Ubuntu"
VERSION_ID="22.04"
VERSION="22.04.1 LTS (Jammy Jellyfish)"
VERSION_CODENAME=jammy
ID=ubuntu
ID_LIKE=debian
HOME_URL="https://www.ubuntu.com/"
SUPPORT_URL="https://help.ubuntu.com/"
BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
UBUNTU_CODENAME=jammy

然而，其他更多命令有以下例外：

# pro --help
WARNING:root:failed to process /proc/version_signature.

# cat /proc/version_signature
cat: /proc/version_signature: No such file or directory

# pro security-status
failed to process /proc/version_signature.

看起来内核无法以某种方式启动专业客户端。

有人遇到同样的问题吗？多谢。