I was able to fix it post-install with the live cd using the following procedure: (where sda3 is my trusty install and sda1 is the EFI system partition)
sudo mount /dev/sda3 /mnt sudo mount -o bind /dev /mnt/dev sudo mount -o bind /sys /mnt/sys sudo mount -t proc /proc /mnt/proc sudo cp /proc/mounts /mnt/etc/mtab sudo cp /etc/resolv.conf /mnt/etc/resolv.conf sudo chroot /mnt /bin/bash apt-get install grub-efi-amd64 mount /dev/sda1 /boot/efi grub-install --target=x86_64-efi --efi-directory=/boot/efi --bootloader-id=grub --recheck --debug grub-mkconfig -o /boot/efi/EFI/GRUB/grub.cfg update-grub -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1287573 Title: GRUB EFI fails to install on MacBook Air 5-2 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/grub-installer/+bug/1287573/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
