Bug#984760: grub-pc: upgrade works, boot fails (error: symbol `grub_is_lockdown` not found)

[Sunil Mohan Adapa]

On Thu, 15 Apr 2021 23:00:22 -0700 Sunil Mohan Adapa <sunil at medhas.org>
wrote:
> Hi,
> 
> The problem is not limited to amd64. I see this problem on arm64. On a
> FreedomBox arm64 image, on a Raspberry Pi 3B+ (when booted with UEFI
> firmware[1]) when grub efi packages are upgraded, boot fails with the
> error 'symbol `grub_is_lockdown` not found'.
> 
> Links:
> 1) https://github.com/pftf/RPi3
> 

In my case, after uninstalling and reinstalling grub-efi-arm64* and
grub?-common packages, everything worked well. This action installed
additional packages (like shim-signed?) that were not present before.

The problem surfaced after an upgrade, in my case, done using
unattended-upgrades. This may indicate that something that is supposed
to be in Depends: list is in Recommends: list.

-- 
Sunil