Old kernel files aren't completely autoremoved

[g]

Hello everyone,

I'm a KDE neon user and noticed that on my installation, the required hard disc space keeps increases after each kernel update. The reason is that after installing a new kernel, old one's files are kept in '/usr/lib/modules/X.X.X-XX-generic/' and '/usr/src/linux-headers-X.X.X-XX/'. The old kernels can be manually removed using the package management which frees the space, however a simple autoremove does not delete the files.

In the respective topic I created at the KDE neon forum (https://forum.kde.org/viewtopic.php?f=309&t=169067), this bug is caused by ubuntu's kernel management that incorrectly marks the old kernel packages as manually installed while upgrading them. Therefore I quickly wanted to report this bug (hoping that it's not a duplicate, at least I did not find one).

[Ubuntu Foundations Team Bug Bot (crichton)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. It seems that your bug report is not filed about a specific source package though, rather it is just filed against Ubuntu in general. It is important that bug reports be filed about source packages so that people interested in the package can find the bugs about it. You can find some hints about determining what package your bug might be about at https://wiki.ubuntu.com/Bugs/FindRightPackage. You might also ask for help in the #ubuntu-bugs irc channel on Freenode.

To change the source package that this bug is filed about visit https://bugs.launchpad.net/ubuntu/+bug/1907887/+editstatus and add the package name in the text box next to the word Package.

[This is an automated message. I apologize if it reached you inappropriately; please just reply to this message indicating so.]

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Mahendra Tallur (mahen)]

Hi ! An important side effect is that, after several months/years, updates take an increasing amount time due to the presence of many unused kernels.

Now that some distros (incl. Neon) use offline updates (applied after rebooting), it gives the feeling the update stopped / crashed.

[Mahendra Tallur (mahen)]

As KDE Neon uses Ubuntu LTS, does it also affect regular Ubuntu installations ?
I would be surprised as the bug is extremely obvious after a few months.
What can we do to help fix it ?

Meanwhile, I use this command to mark old kernels as manually installed so that they get remove with "apt-get autoremove" :

sudo apt-mark auto $(apt-mark showmanual | grep -E "^linux-([[:alpha:]]+-)+[[:digit:].]+-[^-]+(|-.+)$")

[sultan (sultanqasim)]

I'm facing the same issue on the latest KDE Neon. I had to use the command Mahendra mentioned to allow old kernels to be autoremoved and free up around 15 GB of disk space.