[RFC] initoverlayfs - a scalable initial filesystem

[Luca Boccassi]

On Fri, 8 Dec 2023 at 19:00, Eric Curtin <ecurtin at redhat.com> wrote:
>
> We have been working on a new initial filesystem called initoverlayfs.
> It is a new filesystem that provides a more scalable approach to
> initial filesystems as opposed to just using initrds. We are writing
> this RFC to the systemd and dracut mailing lists (feel free to forward
> to UAPI group also) because although this solution works without
> changing the code in these projects, it operates in the same area as
> systemd, udev, dracut, etc. and uses these tools.

It seems to me everything you described already exists? If you want to
avoid having an initrd -> rootfs transition, you can already do that -
the initrd code paths run because there's /etc/initrd-release, omit
that and the transition/phase is avoided. If you want to have an
overlay with r/o images, you can already do that with sysexts. You'll
need to reimplement and maintain separately TPM support, LUKS support,
fido2, etc etc