Comment # 1 on bug 967590 from Michael Chang

xen-4.5.2_04-9.efi is loaded from the $cmdpath and it seems to be wrong here. I
think it's related with your multiboot setup as it seems
./efi/EFI/grub/grub.efi (or shim.efi) was loaded by the firmware in the first
place, which will set the $cmdpath to ./efi/EFI/grub. But I can not figure out
why it will try to load the xen-4.5.2_04-9.efi configured in other distributor
directory (opensuse). 

Would you please attach your /boot/grub2/grub.cfg and 'efibootmgr -v' output ?
Thanks.