Re: [PATCH] Change "efi" to "EFI" in grub-mkrescue for secure boot

[Pascal Hambourg]

On 07/09/2024 at 10:30, Thomas Schmitt via Grub-devel wrote:
> Pascal Hambourg wrote:
> > When
> > booting from a EFI partition on a regular disk, then $root is set to the
> > EFI partition (hdX,Y). When booting from a EFI El Torito image on a CD,
> > then $root is set to the whole CD (cdX), and the El Torito image is not
> > visible.
(...)
> There remains my curiosity why this difference between booting via
> El Torito and via partition table from the same FAT filesystem exists
> and whether this is a bug.

From what I can see in EFI shell, UEFI maps El Torito images as block 
devices, like partitions, but I suppose that GRUB uses only block 
devices which map to entire drives and maps partitions with its own 
partition table drivers (and has no El Torito driver).