Fix sysext driver/mods loading in initrd

[jumpyvi]

Currently, all the drivers parts ending with -initrd are not being used, since they are merged much AFTER sysroot.

Systemd has a solution for this, called systemd-sysext-sysroot, sadly, it's only available in systemd 261, I believe we might be able to just add the unit file to our custom systemd-container package in the ppa. There might also be other under-the-hood systemd-sysext changes in 261 i'm not seeing.

It can't really be added via mkosi, since that would require creating a custom initrd, which is pretty annoying. systemd-container is already in InitrdPackages=, so it should work.

If it doesn't work, I will have to make runtime systemd unit to reload the drivers manually when the session loads, which is not ideal.
And remove all the -initrd transfer.

[jumpyvi]

For future reference, the initrd transfer files:

[Transfer]
ProtectVersion=%A
Features=driver-broadcom
Verify=yes

[Source]
Type=url-file
Path=https://%W.updates.elementaryos.org/%a/ext
MatchPattern=driver-broadcom-modules-%a_@v.raw.zst

[Target]
Type=regular-file
Path=/EFI/Linux/elementary_%A_%a.efi.extra.d/
PathRelativeTo=boot
MatchPattern=driver-broadcom-modules-%a_@v.raw
Mode=0444
InstancesMax=2


[Transfer]
ProtectVersion=%A
Features=driver-nvidia
Verify=yes

[Source]
Type=url-file
Path=https://%W.updates.elementaryos.org/%a/ext
MatchPattern=driver-nvidia-modules-%a_@v.raw.zst

[Target]
Type=regular-file
Path=/EFI/Linux/elementary_%A_%a.efi.extra.d/
PathRelativeTo=boot
MatchPattern=driver-nvidia-modules-%a_@v.raw
Mode=0444
InstancesMax=2

[lewisgoddard]

Your first plan is better than the solution I was thinking of:

systemd-sysext-sysroot runs systemd-sysext --root=/sysroot refresh in the initrd, before the switch to the real root. It merges /sysroot/var/lib/extensions into the real /usr, so the drivers are already in place when the real system's udev first scans the hardware. That fixes Broadcom and NVIDIA with no retrigger of udevadm at all.

[lewisgoddard]

I am of the opinion that elementary/os-patches#366 fixes this without the need to re-introduce the intrid files like in #887. New daily builds with that PPA fix aren't out yet, but are building now.