@ijohnson ok thx for feedback I am looking at tip of this repo:
Currently " 2021-04-26 [UBUNTU: Ubuntu-pi-5.4.0-1035.38]"
so I guess a new version will be released soon.
Meanwhile I’ve tried Pi3 with an external RTC module (pcf8563) but I am afraid it won’t work on current base as I commented at:
I’ll try to rebuild kernel maybe later but I am unsure this can be done without signing it using canonical keys, BTW I’ll be curious to know if it is possible to rebuild from scratch all snaps from UC, and if this is documented anywhere.
Well, I’ve found some hints on this page:
(but IMHO it can be more detailed on how to use tools)
Sorry if i am drifting a bit from the subject of this thread, but it might also help other blocked users.
To be clear about my steps above, step 3 is now done - version 45 of ubuntu-core-initramfs is now released to the snappy-dev image PPA, so we just need the 20 channel of the pi-kernel to be rebuilt to pick it up (step 4).
For the pi, since you don’t need to sign it with EFI keys or anything like that the way you need to do for amd64 due to UEFI, you can just rebuild the kernel and use a dangerous model assertion. I have not build the pi-kernel myself before, but I understand it to be a bit complicated, perhaps @ogra or @ondra have some pointers on how to build a kernel snap for UC20
At some point we should definitely have a doc page about how to build all the snaps from scratch like this, but it would take a while to get everything together for that
Totally not complicated … for custom kernels that do not need to be built from the binary deb the kernel trees all ship a snapcraft.yaml in the top-level of the tree … you just call snapcraft when in the tree … (current snapcraft does not support --target-arch so you need to do it on the native target architecture)