Upon further inspection: The flash-kernel from the rpi3 PPA https://launchpad.net/~ubuntu-raspi2/+archive/ubuntu/ppa-rpi3 is only published for Xenial and there, the boot script sets the fdt address to 0x100 instead of 0x2000000. And that works without explicitly loading the fdt.
So it seems I had the "old" flash-kernel from before upgrading to Yakkety and that worked. The new version tries to load the fdt from 0x2000000 where it isn't located. ** Also affects: flash-kernel (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1652504 Title: Recent updates broke Ubuntu on Raspberry Pi 3 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/flash-kernel/+bug/1652504/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs