Host OS: Arch Linux uname: Linux 6.6.1-arch1-1 #1 SMP PREEMPT_DYNAMIC x86_64 GNU/Linux mkosi: v19

Description

Including dracut in the Packages value causes various boot-up scripts and other code to be embedded at the beginning of the UKI. For example, here's an lsinitrd output:

OS Release: Arch Linux (arch-rolling)
Kernel Version: 6.6.1-arch1-1 (linux@archlinux) #1 SMP PREEMPT_DYNAMIC Wed, 08 Nov 2023 16:05:38 +0000
Command line:
systemd.volatile=overlay
========================================================================
/usr/bin/lsinitrd: line 368: warning: command substitution: ignored null byte in input
Version: #!/bin/bash
#
# functions used by dracut and other tools.
#
# Copyright 2005-2009 Red Hat, Inc.  All rights reserved.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
export LC_MESSAGES=C

The problem is that it always does this, even for Format=uki & MakeInitrd=no output, which isn't necessary since those images aren't intended to be initramfs' which transition to a "real" system.

Ideally, MakeInitrd=no (maybe in combination with Format=uki if that's too broad) would skip this content being included.

Configs

See the config in this comment as an example, and use lsinitrd /path/to/uki | less to see the included dracut content at the beginning of the UKI.

systemd / mkosi

Dracut always embeds its scripts into UKIs, even non-initramfs ones #2080

Description

Configs