Comment # 8 on bug 1122614 from Michael Chang

(In reply to Guillaume GARDET from comment #6)
> Also broken on Chromebook ARM, but I cannot give much details on this
> failure as I have no serial on this device and screen goes back to grub menu.
> 
> bootarm.efi is very light now, around 170KB instead of 750KB previously.

I compared the kernel.img size between packages in Base:System and 2.04,
there's no much difference (88KB vs 87KB).

Looks like the comparison is between /boot/grub2/arm-efi/grub.efi and
bootarm.efi created by grub2-install. The first is created in OBS with lots of
modules builtin, used in boot media, secure boot and so on. The latter is
created wrt the runtime system by grub2-install, only with minimum required
modules built-in.

Hm. Now that it seems to me the serial console problem could be related. Try if
this work ? 

  grub2-install --modules=serial

> If I re-use the file from /boot/grub2/arm-efi/grub.efi from rootfs partition
> (not updated apparently) and copy it to (EFI part)/EFI/BOOT/bootarm.efi it
> does boot again.
> 
> If I copy /usr/share/grub2/arm-efi/grub.efi, then it does fail too.

The failure might be in the same efistub, we can check by new kernel update
after we have it fixed.