Bug#1035332: grub-efi-arm64: "error: failed to install/update FDT." after bullseye upgrade

[Steve McIntyre]

On Mon, May 01, 2023 at 12:08:38PM -0700, Vagrant Cascadian wrote:
>On 2023-04-30, Vagrant Cascadian wrote:
>> After updating to the latest point release, these apm mustang systems
>> fail to boot the kernel, all I see is:
>>
>>     error: failed to install/update FDT.
>>     Loading Linux 5.10.0-22-arm64 ...
>>     Loading initial ramdisk ...
>>
>>     Press any key to continue...
>
>The workaround was to uninstall shim-signed and re-install grub
>(grub-install /dev/sda ; grub-install /dev/sdb).
>
>Worked for three of three machines so far... I tested re-installing
>shim-signed on one machine and re-installing grub and the problem came
>back.
>
>No idea why this started happening just now, as shim-signed and related
>packages were all installed before the bullseye point release, but did
>not have this problem...

As described in IRC, I can reproduce this on a mustang here. The grub
binary itself is fine, and boots ok when started directly from the
firmware. But put shim in first and things break. I've turned debug up
to see what's happening.

On a working boot, I can see:

...
kern/efi/fdt.c:38: found registered FDT @ 0x43fd2c3000
loader/efi/fdt.c:63: allocating 26028 bytes for fdt
loader/arm64/linux.c:90: Initrd @ 0x43924fc000-0x4393fff69a
loader/efi/fdt.c:98: Installed/updated FDT configuration table @ 0x43f8b70000
...

On a failing boot:
...
kern/efi/fdt.c:38: found registered FDT @ 0x43fd2c4000
loader/efi/fdt.c:63: allocating 26028 bytes for fdt
error: failed to install/update FDT.
...

Digging further...

-- 
Steve McIntyre, Cambridge, UK.                                steve at einval.com
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