[Kivutar]

Some years ago, I was developing a Linux distro for embedded systems. Some of these embedded systems come with old kernels, and you will never get a recent kernel for them.

Systemd is written in C and relies on kernel headers. Which means that they need to have a layer that deals with different versions of the kernel headers. I remember it was headers about network.

At the time I was working on this, I had to contribute to systemd to add support for my kernel version. Got a few patches accepted in their master. And things were working fine for a while.

Until they suddenly decided to drop <= 3.10 kernel support. Yep. Afterwhat I had to maintain patch sets for systemd, which is a great amount of job, given that my upstream was updating systemd quite often.

Now my good people, explain me how such a mess could have happen with a previous init based on shell?

[CaliforniaKarl]

I'm curious: Did systemd drop 3.10 support before the kernel developers stopped supporting it (in 2017, see http://lkml.iu.edu/hypermail/linux/kernel/1711.0/03167.html), or before that? If it was around the same time, then I could understand dropping support, since even the kernel developers had decided to move on.

[jononor]

You could have stayed on an older systemd version? Preferably one used by a major distro, such that someone else might backport security fixes etc for you.

Anyway the root cause here is bad vendor BSPs being stuck on old Linux versions.

[teddyh]

GNU libc 2.26 (released 2017-08-02) requires Linux 3.2 or newer. It’s not like systemd is alone in requiring recent kernels.