security-misc/etc/default/grub.d/41_quiet_boot.cfg

## Copyright (C) 2019 - 2024 ENCRYPTED SUPPORT LP <adrelanos@whonix.org>
## See the file COPYING for copying conditions.

## Some default configuration files automatically include the "quiet" parameter.
## Therefore, first remove "quiet" from GRUB_CMDLINE_LINUX_DEFAULT since "quiet" must be first.
## LANG=C str_replace is provided by package helper-scripts.
##
## https://github.com/Kicksecure/security-misc/pull/233#issuecomment-2228792461
##
GRUB_CMDLINE_LINUX_DEFAULT="$(echo "$GRUB_CMDLINE_LINUX_DEFAULT" | LANG=C str_replace "quiet" "")"

## Prevent sensitive kernel information leaks in the console during boot.
## Must be used in combination with the kernel.printk sysctl.
## See /usr/lib/sysctl.d/30_silent-kernel-printk.conf for implementation.
##
## https://www.kernel.org/doc/html/latest/core-api/printk-basics.html
## https://wiki.archlinux.org/title/silent_boot
##
## For easier debugging, these are not applied to the recovery boot option.
## Switch the pair of commands to universally apply parameters to all boot options.
##
GRUB_CMDLINE_LINUX_DEFAULT="$GRUB_CMDLINE_LINUX_DEFAULT loglevel=0"
GRUB_CMDLINE_LINUX_DEFAULT="$GRUB_CMDLINE_LINUX_DEFAULT quiet"
#GRUB_CMDLINE_LINUX="$GRUB_CMDLINE_LINUX loglevel=0"
#GRUB_CMDLINE_LINUX="$GRUB_CMDLINE_LINUX quiet"

## For Increased Log Verbosity:
## Adjust (or comment out) the kernel.printk sysctl in /usr/lib/sysctl.d/30_silent-kernel-printk.conf.
## Alternatively, installing the debug-misc package will undo these settings.