"linux-modules-cleanup.service" is not automatically called on Kernel updates

[Daniel-I]

There’s been a few weeks of idleness, so I think it’s time to put together the best solution post I can… as the solution is multi-fold depending on your course of action.

To answer the original question/issue about why clean-up in the /lib/modules/ folder was not happening… it really boils down to knowing the tool you are trying to use; whether that be kernel-alive or (in my case) kernel-modules-hook. As it turns out, even though I’d installed the package, I had not started/enabled its service for it to be used/called…

@Daniel-I

Hmm, if that’s correct, then (while using kernel-modules-hook) it seems to support my evolving thinking that running $ systemctl enable linux-modules-cleanup.service was important for it’s symlink to be created… Created symlink /etc/systemd/system/basic.target.wants/linux-modules-cleanup.service → /usr/lib/systemd/system/linux-modules-cleanup.service.

I feel that step alone would have resolved my original question… but was kernel-modules-hook even required in my case?

@Please use kernel-modules-hook instead of kernel-alive!

The packages was created so a functional kernel was available even after syncing a new kernel package.

The reboot was often postponed for days and users forgot they had updated and suddenly the system malfunctions - which in turn created the idea of this set of packages.

I have never used the package and the editions I have maintained does not include this package and on occasion I have recommended to uninstall the packages.

So seeing as I always reboot after applying system updates manually, tools like kernel-alive and kernel modules-hook aren’t required… and in my use case, the best solution was to remove the package/service entirely.

1. Don’t forget to shutdown the services; which will purge its symlinks before removal

@linux-aarhus

The removal of the package could have removed then but the package doesn’t really know if the service was enabled or not - so before removing a package with a service which has been enabled manually one should disable the service - which will remove the symlink.

sudo systemctl disable --now some.service

When the package has been removed before the service was disabled - you can still remove the symlink using

sudo systemctl disable --now linux-modules-cleanup.service linux-module-cleanup.service

You may get a message - you can safely ignore it.

2. and uninstall the application/service…

@Please use kernel-modules-hook instead of kernel-alive!

You can safely remove the packages

sudo pacman -Rns kernel-alive kernel-modules-hook

Did uninstalling kernel-modules-hook enable/allow the default hooks/process during an update to clean-up the /lib/modules folder? Yes it did! (with one minor clean-up required; a folder created by the package)

@Daniel-I

So today was a new stable update with a shiny new kernel… and I was finally able to see whether or not the /lib/modules folder was cleared of the previous kernel’s folders/files in a “default” configuration… i.e. without kernel-alive and kernel-modules-hook. And the verdict is… yes it was!

$ ls -la /lib/modules 
total 280
drwxr-xr-x  11 root root   4096 Feb 14 13:05 .
drwxr-xr-x 240 root root 241664 Feb 14 13:05 ..
drwxr-xr-x   3 root root   4096 Feb 14 13:05 5.10.98-1-MANJARO
drwxr-xr-x   3 root root   4096 Nov 29 21:01 5.13.19-2-MANJARO
drwxr-xr-x   3 root root   4096 Dec 10 14:52 5.14.21-2-MANJARO
drwxr-xr-x   3 root root   4096 Feb 14 13:05 5.15.21-1-MANJARO
drwxr-xr-x   2 root root   4096 Feb 14 13:05 extramodules-5.10-MANJARO
drwxr-xr-x   2 root root   4096 Nov 29 21:01 extramodules-5.13-MANJARO
drwxr-xr-x   2 root root   4096 Dec 10 14:52 extramodules-5.14-MANJARO
drwxr-xr-x   2 root root   4096 Feb 14 13:05 extramodules-5.15-MANJARO
drwxr-xr-x   5 root root   4096 Feb  5 11:10 .old

Huzzah, only one 5.15.* kernel folder!

This did however show a minor necessary manual cleanup/removal of the /lib/modules/.old folder left behind by the uninstall of kernel-modules-hook with the command $ sudo rm -dr /lib/modules/.old/