bug#26815: [PATCH 3/3] vm: Support EFI boot in base image.

[Danny Milosavljevic]

Hi Marius,

> +      (system* "grub-mkstandalone" "-O" "x86_64-efi" "-o"
> +               (string-append efi-directory "/EFI/BOOT/BOOTX64.EFI")
> +               ;; Embed the contents of grubdisk.cfg.
> +               (string-append "boot/grub/grub.cfg=" target
> +                              "/tmp/grubdisk.cfg"))

Check return value of system* ?

>                    (partitions (list (partition
>                                       (size #$(- disk-image-size
> -                                                (* 10 (expt 2 20))))
> +                                                (* 50 (expt 2 20))))

<https://wiki.archlinux.org/index.php/EFI_System_Partition> says:

>According to a Microsoft note[2], the minimum size for the EFI System 
>Partition (ESP) would be 100 MB, though this is not stated in the UEFI 
>Specification. Note that for Advanced Format 4K Native drives 
>(4-KB-per-sector) drives, the size is at least 256 MiB, because it is the 
>minimum partition size of FAT32 drives (calculated as sector size (4KB) x 
>65527 = 256 MiB), due to a limitation of the FAT32 file format. 

Is this relevant for us?

Also, <https://gist.github.com/Apsu/4108795> says that F32 is not required for 
most UEFI firmwares. FAT12, FAT32 usually work.  But better be safe than sorry, 
I guess.

> +                                     (size (* 40 (expt 2 20)))
> +                                     (label "gnu-esp")
> +                                     (file-system "vfat")

Is it really vfat with long file names and everything? Or only FAT32 (with 
short file names)?

I ask because a lot of UEFT file names look as if they are for FAT32 with their 
short all-uppercase names.