From 6b1324fb867d89147585ee20160dbe8f37beefc8 Mon Sep 17 00:00:00 2001
From: Lennart Poettering <lennart@amutable.com>
Date: Wed, 29 Apr 2026 13:35:41 +0200
Subject: [PATCH] man: add a brief note about type 1 extra lines

---
 man/systemd-stub.xml | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/man/systemd-stub.xml b/man/systemd-stub.xml
index bf23c900d02..95f62ca66b5 100644
--- a/man/systemd-stub.xml
+++ b/man/systemd-stub.xml
@@ -291,6 +291,14 @@
     by <command>systemd-creds encrypt -T</command> (see
     <citerefentry><refentrytitle>systemd-creds</refentrytitle><manvolnum>1</manvolnum></citerefentry> for
     details); in case of the system extension images by using signed Verity images.</para>
+
+    <para>Note that earlier components of the boot process might register additional initrds, and thus
+    additional "companion" resources such as system extensions, configuration extensions and credentials for
+    consumption by the kernel and OS eventually booted. For example,
+    <citerefentry><refentrytitle>systemd-boot</refentrytitle><manvolnum>7</manvolnum></citerefentry> does
+    this for resources configured in UAPI.1 Type #1 <literal>extra</literal>
+    lines. <filename>systemd-stub</filename> will combine any resources provided that way with the companion
+    file resources it acquires itself.</para>
   </refsect1>
 
   <refsect1>
-- 
2.47.3