Bug#1135731: does not boot on raspberry pi 4 (grub_memcpy not found)

[Steve McIntyre]

Hey Pascal,

On Tue, May 05, 2026 at 01:32:17PM +0200, Pascal Hambourg wrote:
>On 05/05/2026 at 12:34, Steve McIntyre wrote:
>> 
>> OK, this is 99.9% certain to be a mismatch between the grub core image
>> and the modules installed in /boot/grub. If you're on a Pi, then it's
>> very likely you're booting using the removable media path.
>
>U-boot logs seem to confirm it:
>
>> > Cannot persist EFI variables without system partition
>
>Without EFI variables, only the removable media path can be used.
>
>If U-Boot loads GRUB from the EFI partition removable media path, it means
>the copy of GRUB core image in /boot/efi/EFI/BOOT/ was not updated after
>upgrading to the new GRUB version. It should be updated automatically if
>grub2/force_efi_extra_removable is set to 'false' in debconf. You can check
>with
>
>debconf-show grub-efi-arm64

Yup, that's exactly where I was going. Unfortunately, lots of people
just end up copying a grub binary into place once (whether by directly
copying, or by using grub-install manually) and that works *now* but
leaves them primed for a fall on future upgrades.

It's been a problem for years with BIOS boot, but we can't 100% solve
that due to the space limitations and needing a core images. Switching
to the monolithic image for EFI is possible, and it's time we just did
it.

-- 
Steve McIntyre, Cambridge, UK.                                steve at einval.com
"This dress doesn't reverse." -- Alden Spiess