bug#47889: [installer image] grub-install efi fails getting canonical path to /boot/efi on dos-formatted disk

[pelzflorian (Florian Pelz)]

When installing from the Guix install image, grub-install fails on my
x86_64 ASRock Beebox PC:

guix system: error: 
'/gnu/store/hsc3gsqbxkl64nx38sf2fgs2fxzbpr0i-grub-efi-2.04/sbin/grub-install 
--boot-directory /mnt/boot --bootloader-id=Guix --efi-directory /boot/efi' 
exited with status 1; output follows:

 Installing for x86_64-efi platform.
 /gnu/store/hsc3gsqbxkl64nx38sf2fgs2fxzbpr0i-grub-efi-2.04/sbin/grub-install: 
error: failed to get canonical path of `/boot/efi'.

I let the Guix installer (git master commit
fef2f08bc640f78cc0a86fc7be3eccbc07b5e98c) auto-partition my entire
disk without encryption.

“fdisk -l /dev/sda” shows:

Disk /dev/sda: 238.49 GiB, 256060514304 bytes, 500118192 sectors
[…]
Disklabel type: dos
Disk identifier: 0xd0416d83

Device     Boot   Start       End   Sectors   Size Id Type
/dev/sda1          2048   7811071   7009024   3.7G 82 Linux swap / Solaris
/dev/sda2  *    7011072 500117583 492306432 234.8G 83 Linux

Regards,
Florian