我有一台运行 Ubuntu 22.04 的 System76 Gazelle 笔记本电脑。我尝试设置 Ubuntu Pro，但总是显示错误An error occurred when checking for Livepatch updates。在排除故障时，我注意到pro命令给出了错误WARNING:root:failed to process /proc/version_signature.
➜ ~ sudo pro status
WARNING:root:failed to process /proc/version_signature.
SERVICE ENTITLED STATUS DESCRIPTION
esm-infra yes enabled Expanded Security Maintenance for Infrastructure
livepatch yes enabled Canonical Livepatch service
realtime-kernel yes disabled Ubuntu kernel with PREEMPT_RT patches integrated
Enable services with: pro enable <service>
Account: ___@___.___
Subscription: Ubuntu Pro - free personal subscription
果然，这个文件丢失了。
➜ ~ cat /proc/version_signature
cat: /proc/version_signature: No such file or directory
我没有对这台机器进行任何真正的极端定制，例如尝试使用自定义内核，所以我不确定为什么这个文件会丢失。关于如何恢复这个文件，有什么想法吗？
编辑：
uname -r显示我运行的是内核 6.0.6。我在 grub 菜单中切换到 5.15.0，现在就/proc/version_signature可以使用了。
➜ ~ cat /proc/version_signature
Ubuntu 5.15.0-56.62-generic 5.15.64
我不确定为什么要安装 6.0 内核。一台相同的笔记本电脑有内核 5.15。尝试卸载 6.0.x 内核会卸载重要的软件包。
➜ ~ sudo apt remove linux-image-6.0.6-76060006-generic
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
The following packages were automatically installed and are no longer required:
amd-ppt-bin at dfu-programmer firmware-manager firmware-manager-notify firmware-manager-shared gnome-shell-extension-system76-power hidpi-daemon linux-headers-6.0.2-76060002
linux-headers-6.0.2-76060002-generic linux-image-6.0.2-76060002-generic linux-modules-6.0.2-76060002-generic python3-evdev python3-pydbus system76-acpi-dkms system76-dkms system76-firmware-daemon
system76-io-dkms system76-oled system76-power system76-wallpapers xbacklight
Use 'sudo apt autoremove' to remove them.
The following packages will be REMOVED:
linux-generic linux-image-6.0.6-76060006-generic linux-image-generic linux-system76 system76-driver system76-driver-nvidia
0 upgraded, 0 newly installed, 6 to remove and 0 not upgraded.
After this operation, 12.6 MB disk space will be freed.
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