Consider alternatives to overlayroot

[UriHerrera]

With Linux 6.5, overlayroot does not work anymore; see #133.

I've no idea why or how. All I know is that it only works with kernels up to 6.4.15. Unfortunately, this isn't a trivial matter since the Nitrux Update Tool System is affected, too.

I've searched for alternatives. However, there's no natural alternative on the horizon.

1. OSTree does not support initramfs-tools, only dracut, and it's highly dependent on Systemd and, as far as I can tell, BTRFS; see rpm-ostree for example.
2. Debian "supports" dracut as much as it "supports" OpenRC, so there's that. In other words, there is a package, but anything that uses initramfs hooks targets initramfs-tools (so, literally everything in Debian).
3. I found a project called fsprotect; however, it depends on AUFS.
4. I also found another project called Bilibop, which depends on AUFS too.
5. Debian does not support AUFS, so there's that. Specifically, Debian does have packages for AUFS version 5.2, which is no longer supported by its developer, and it does not have support for newer kernels because AUFS version 6 is the latest.

[UriHerrera]

I've updated the original issue: #133.

TL;DR

Seemingly a change in how the kernel parameter ro works causes the root to be read-only. It is the purpose of that parameter to do that precisely per its documentation; however, using the same parameter in previous kernels (pre-6.5) didn't cause an adverse effect.

When I remove the parameter and boot, there are no problems, and the overlay works as expected. So, the root remains immutable even if I use a newer kernel, in this case, 6.5.11-1.

Therefore, I'll change the title of this discussion as overlayroot does work, but that parameter is causing the issue. Nonetheless, I don't know what adds that parameter.

[UriHerrera]

I've made some changes that will take care of removing the parameter. However, for future-proofing, we should look for an alternative to overlayroot.

Maybe implement some of the things that znx did well.