It was not an option to keep my system broken for longer, so I mounted my system disk to a working Ubuntu installation and used 'dpkg --root=/mnt --force-script-chrootless -i ...' from there for getting libc installed, after which a native apt install -f was able to take it from there.
Let's hope that this was really really a one-off error nobody else will see because I will not be able to provide any further information with something like 1500+ packages now having been upgraded. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1943124 Title: Upgrade fails due to "text file busy" To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/glibc/+bug/1943124/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs