On 17/12/2023 at 12:08, Albretch Mueller wrote:
Say I burn a DVD with the debian bootable iso (the live DVD) for
amd64, arm64 and 64-bit risc-v processors
Debian does not provide any such multi-arch ISO image. Until bookworm it
provided a amd64+i386 multi-arch image which was able to boot with PC
BIOS (with ISOLinux, 32-bit x86 UEFI and 64-bit x86 UEFI (with GRUB).
will GRUB2 automatically
detect the architecture and pick the file?
Let's assume you you create such an ISO image for UEFI boot only. It
must contain an EFI partition with EFI images for each firmware
architecture : bootarm64.efi (built for ARM64), bootx64.efi (built for
AMD64/x86_64) and bootriscv64.efi (built for RISC-V64). The UEFI
firmware will seek the matching EFI image, and the GRUB image will
report the architecture in $grub_cpu and $grub_platform.