I have only carried out an update and after the update a Grub password was set under /etc/grub.d/07_passwd
#!/bin/sh
#------------------------------------------------------------------------------Modified Calculate Utilities 3.7.6.8
Processed template files:
/var/db/repos/calculate/profiles/templates/2_ac_install_merge/sys-boot/grub/grub.d/07_passwd
To modify this file, create a /etc/grub.d/07_passwd.clt template.
#------------------------------------------------------------------------------
grub-mkconfig helper script.
Copyright 2016 Calculate Ltd. http://www.calculate-linux.org
Licensed under the Apache License, Version 2.0 (the “License”);
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
Apache License, Version 2.0
cat <<EOF
set superusers=“root”
password_pbkdf2 root grub.pbkdf2.sha512.25000.8811E27C0F21C4F8BF17C2F87FAFD51AE39C73AE15C2D8FBBF9732C6D8BB772EC578AF558A1122C4B837C6D8BB17628C114228254488D17AAF15024088712E25.C1F64B01030B7BCF71646CBCC6DED813C64F4FA5653C3A8CC0B0CC5C34A9CC84F9F6BED3E040F44508826FD957C5714733C07ACA9CE66E44FCC07484F8B636A8
export superusers
EOF
I didn’t create the file, I don’t know where it came from. I used the following to update my system, it took a while because it is an old laptop and there was an KDE update and there were many ~amd64 packages to compile:
emaint -A sync && eix-update && emerge -avNDuq --keep-going --with-bdeps=y --complete-graph --verbose-conflicts @world && smart-live-rebuild && emerge @module-rebuild -q && emerge -aqv --depclean && emerge -avq --keep-going @preserved-rebuild && grub-install /dev/sda && grub-mkconfig -o /boot/grub/grub.cfg
I changed some useflags on my system, installed some packages from overlays and installed many ~amd64 packages, but I don’t know what should trigger something like this.
I don’t know where the pw hash in /etc/grub.d/07_passwd came from, my passwords didn’t work with it.
I created my own hash and saved it there, and it works.