Huh? The one thing you generally can't update is the kernel since it's the foundation of every other process. I haven't used ubuntu in several years, have things changed drastically?
There were three large patches that were integrated into the Linux kernel in version 4.0 (2014) that make it so that you can live patch the kernel easily. [0][1][2]
(Before these arrived there were already some tool's for it, for some distros. But now everyone should be able to, unless the distro intentionally cripples the ability).
(Before these arrived there were already some tool's for it, for some distros. But now everyone should be able to, unless the distro intentionally cripples the ability).
[0] https://lwn.net/Articles/619390/
[1] https://lwn.net/Articles/622936/
[2] https://lwn.net/Articles/634649/