Adding upstream version 252.22.upstream/252.22

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 602 insertions, 0 deletions

diff --git a/man/kernel-command-line.xml b/man/kernel-command-line.xml
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+<?xml version='1.0'?> <!--*-nxml-*-->
+<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
+  "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
+<!-- SPDX-License-Identifier: LGPL-2.1-or-later -->
+
+<refentry id="kernel-command-line">
+
+  <refentryinfo>
+    <title>kernel-command-line</title>
+    <productname>systemd</productname>
+  </refentryinfo>
+
+  <refmeta>
+    <refentrytitle>kernel-command-line</refentrytitle>
+    <manvolnum>7</manvolnum>
+  </refmeta>
+
+  <refnamediv>
+    <refname>kernel-command-line</refname>
+    <refpurpose>Kernel command line parameters</refpurpose>
+  </refnamediv>
+
+  <refsynopsisdiv>
+    <para><filename>/proc/cmdline</filename></para>
+  </refsynopsisdiv>
+
+  <refsect1>
+    <title>Description</title>
+
+    <para>The kernel, the programs running in the initrd and in the host system may be configured at boot via
+    kernel command line arguments. In addition, various systemd tools look at the EFI variable
+    <literal>SystemdOptions</literal> (if available). Both sources are combined, but the kernel command line
+    has higher priority. Please note that <emphasis>the EFI variable is only used by systemd tools, and is
+    ignored by the kernel and other user space tools</emphasis>, so it is not a replacement for the kernel
+    command line.</para>
+
+    <para>For command line parameters understood by the kernel, please
+    see
+    <ulink url="https://docs.kernel.org/admin-guide/kernel-parameters.html"><filename>kernel-parameters.html</filename></ulink>
+    and
+    <citerefentry project='man-pages'><refentrytitle>bootparam</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para>
+
+    <para>For command line parameters understood by the initrd, see
+    <citerefentry project='man-pages'><refentrytitle>dracut.cmdline</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
+    or the documentation of the specific initrd implementation of your
+    installation.</para>
+  </refsect1>
+
+  <refsect1>
+    <title>Core OS Command Line Arguments</title>
+
+    <variablelist class='kernel-commandline-options'>
+      <varlistentry>
+        <term><varname>systemd.unit=</varname></term>
+        <term><varname>rd.systemd.unit=</varname></term>
+        <term><varname>systemd.dump_core</varname></term>
+        <term><varname>systemd.crash_chvt</varname></term>
+        <term><varname>systemd.crash_shell</varname></term>
+        <term><varname>systemd.crash_reboot</varname></term>
+        <term><varname>systemd.confirm_spawn</varname></term>
+        <term><varname>systemd.service_watchdogs</varname></term>
+        <term><varname>systemd.show_status</varname></term>
+        <term><varname>systemd.status_unit_format=</varname></term>
+        <term><varname>systemd.log_target=</varname></term>
+        <term><varname>systemd.log_level=</varname></term>
+        <term><varname>systemd.log_location=</varname></term>
+        <term><varname>systemd.log_color</varname></term>
+        <term><varname>systemd.default_standard_output=</varname></term>
+        <term><varname>systemd.default_standard_error=</varname></term>
+        <term><varname>systemd.setenv=</varname></term>
+        <term><varname>systemd.machine_id=</varname></term>
+        <term><varname>systemd.set_credential=</varname></term>
+        <term><varname>systemd.import_credentials=</varname></term>
+        <listitem>
+          <para>Parameters understood by the system and service
+          manager to control system behavior. For details, see
+          <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>systemd.mask=</varname></term>
+        <term><varname>systemd.wants=</varname></term>
+        <term><varname>systemd.debug_shell</varname></term>
+        <listitem>
+          <para>Additional parameters understood by
+          <citerefentry><refentrytitle>systemd-debug-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+          to mask or start specific units at boot, or invoke a debug
+          shell on tty9.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>systemd.run=</varname></term>
+        <term><varname>systemd.run_success_action=</varname></term>
+        <term><varname>systemd.run_failure_action=</varname></term>
+        <listitem>
+          <para>Additional parameters understood by
+          <citerefentry><refentrytitle>systemd-run-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>, to
+          run a command line specified on the kernel command line as system service after booting up.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>systemd.early_core_pattern=</varname></term>
+        <listitem>
+          <para>During early boot, the generation of core dump files is disabled until a core dump handler (if any)
+          takes over. This parameter allows specifying an absolute path where core dump files should be stored until
+          a handler is installed. The path should be absolute and may contain specifiers, see
+          <citerefentry project='man-pages'><refentrytitle>core</refentrytitle><manvolnum>5</manvolnum></citerefentry> for details.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>systemd.restore_state=</varname></term>
+        <listitem>
+          <para>This parameter is understood by several system tools
+          to control whether or not they should restore system state
+          from the previous boot. For details, see
+          <citerefentry><refentrytitle>systemd-backlight@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+          and
+          <citerefentry><refentrytitle>systemd-rfkill.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
+          </para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>systemd.volatile=</varname></term>
+        <listitem>
+          <para>This parameter controls whether the system shall boot up in volatile mode. Takes a boolean argument, or
+          the special value <literal>state</literal>. If false (the default), normal boot mode is selected, the root
+          directory and <filename>/var/</filename> are mounted as specified on the kernel command line or
+          <filename>/etc/fstab</filename>, or otherwise configured. If true, full state-less boot mode is selected. In
+          this case the root directory is mounted as volatile memory file system (<literal>tmpfs</literal>), and only
+          <filename>/usr/</filename> is mounted from the file system configured as root device, in read-only mode. This
+          enables fully state-less boots were the vendor-supplied OS is used as shipped, with only default
+          configuration and no stored state in effect, as <filename>/etc/</filename> and <filename>/var/</filename> (as
+          well as all other resources shipped in the root file system) are reset at boot and lost on shutdown. If this
+          setting is set to <literal>state</literal> the root file system is mounted read-only, however
+          <filename>/var/</filename> is mounted as a volatile memory file system (<literal>tmpfs</literal>), so that the
+          system boots up with the normal configuration applied, but all state reset at boot and lost at shutdown. If
+          this setting is set to <literal>overlay</literal> the root file system is set up as
+          <literal>overlayfs</literal> mount combining the read-only root directory with a writable
+          <literal>tmpfs</literal>, so that no modifications are made to disk, but the file system may be modified
+          nonetheless with all changes being lost at reboot. For details, see
+          <citerefentry><refentrytitle>systemd-volatile-root.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+          and
+          <citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>quiet</varname></term>
+        <listitem>
+          <para>Parameter understood by both the kernel and the system
+          and service manager to control console log verbosity. For
+          details, see
+          <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>debug</varname></term>
+        <listitem>
+          <para>Parameter understood by both the kernel and the system
+          and service manager to control console log verbosity. For
+          details, see
+          <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>-b</varname></term>
+        <term><varname>rd.emergency</varname></term>
+        <term><varname>emergency</varname></term>
+        <term><varname>rd.rescue</varname></term>
+        <term><varname>rescue</varname></term>
+        <term><varname>single</varname></term>
+        <term><varname>s</varname></term>
+        <term><varname>S</varname></term>
+        <term><varname>1</varname></term>
+        <term><varname>2</varname></term>
+        <term><varname>3</varname></term>
+        <term><varname>4</varname></term>
+        <term><varname>5</varname></term>
+        <listitem>
+          <para>Parameters understood by the system and service
+          manager, as compatibility and convenience options. For details, see
+          <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>locale.LANG=</varname></term>
+        <term><varname>locale.LANGUAGE=</varname></term>
+        <term><varname>locale.LC_CTYPE=</varname></term>
+        <term><varname>locale.LC_NUMERIC=</varname></term>
+        <term><varname>locale.LC_TIME=</varname></term>
+        <term><varname>locale.LC_COLLATE=</varname></term>
+        <term><varname>locale.LC_MONETARY=</varname></term>
+        <term><varname>locale.LC_MESSAGES=</varname></term>
+        <term><varname>locale.LC_PAPER=</varname></term>
+        <term><varname>locale.LC_NAME=</varname></term>
+        <term><varname>locale.LC_ADDRESS=</varname></term>
+        <term><varname>locale.LC_TELEPHONE=</varname></term>
+        <term><varname>locale.LC_MEASUREMENT=</varname></term>
+        <term><varname>locale.LC_IDENTIFICATION=</varname></term>
+        <listitem>
+          <para>Parameters understood by the system and service
+          manager to control locale and language settings. For
+          details, see
+          <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>fsck.mode=</varname></term>
+        <term><varname>fsck.repair=</varname></term>
+
+        <listitem>
+          <para>Parameters understood by the file system checker
+          services. For details, see
+          <citerefentry><refentrytitle>systemd-fsck@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>quotacheck.mode=</varname></term>
+
+        <listitem>
+          <para>Parameter understood by the file quota checker
+          service. For details, see
+          <citerefentry><refentrytitle>systemd-quotacheck.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>systemd.journald.forward_to_syslog=</varname></term>
+        <term><varname>systemd.journald.forward_to_kmsg=</varname></term>
+        <term><varname>systemd.journald.forward_to_console=</varname></term>
+        <term><varname>systemd.journald.forward_to_wall=</varname></term>
+
+        <listitem>
+          <para>Parameters understood by the journal service. For
+          details, see
+          <citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>vconsole.keymap=</varname></term>
+        <term><varname>vconsole.keymap_toggle=</varname></term>
+        <term><varname>vconsole.font=</varname></term>
+        <term><varname>vconsole.font_map=</varname></term>
+        <term><varname>vconsole.font_unimap=</varname></term>
+
+        <listitem>
+          <para>Parameters understood by the virtual console setup logic. For details, see
+          <citerefentry><refentrytitle>vconsole.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>udev.log_level=</varname></term>
+        <term><varname>rd.udev.log_level=</varname></term>
+        <term><varname>udev.children_max=</varname></term>
+        <term><varname>rd.udev.children_max=</varname></term>
+        <term><varname>udev.exec_delay=</varname></term>
+        <term><varname>rd.udev.exec_delay=</varname></term>
+        <term><varname>udev.event_timeout=</varname></term>
+        <term><varname>rd.udev.event_timeout=</varname></term>
+        <term><varname>udev.timeout_signal=</varname></term>
+        <term><varname>rd.udev.timeout_signal=</varname></term>
+        <term><varname>udev.blockdev_read_only</varname></term>
+        <term><varname>rd.udev.blockdev_read_only</varname></term>
+        <term><varname>net.ifnames=</varname></term>
+        <term><varname>net.naming-scheme=</varname></term>
+
+        <listitem>
+          <para>Parameters understood by the device event managing
+          daemon. For details, see
+          <citerefentry><refentrytitle>systemd-udevd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>plymouth.enable=</varname></term>
+
+        <listitem>
+          <para>May be used to disable the Plymouth boot splash. For
+          details, see
+          <citerefentry project='die-net'><refentrytitle>plymouth</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>luks=</varname></term>
+        <term><varname>rd.luks=</varname></term>
+        <term><varname>luks.crypttab=</varname></term>
+        <term><varname>rd.luks.crypttab=</varname></term>
+        <term><varname>luks.name=</varname></term>
+        <term><varname>rd.luks.name=</varname></term>
+        <term><varname>luks.uuid=</varname></term>
+        <term><varname>rd.luks.uuid=</varname></term>
+        <term><varname>luks.options=</varname></term>
+        <term><varname>rd.luks.options=</varname></term>
+        <term><varname>luks.key=</varname></term>
+        <term><varname>rd.luks.key=</varname></term>
+
+        <listitem>
+          <para>Configures the LUKS full-disk encryption logic at
+          boot. For details, see
+          <citerefentry><refentrytitle>systemd-cryptsetup-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>fstab=</varname></term>
+        <term><varname>rd.fstab=</varname></term>
+
+        <listitem>
+          <para>Configures the <filename>/etc/fstab</filename> logic
+          at boot. For details, see
+          <citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>root=</varname></term>
+        <term><varname>rootfstype=</varname></term>
+        <term><varname>rootflags=</varname></term>
+        <term><varname>ro</varname></term>
+        <term><varname>rw</varname></term>
+
+        <listitem>
+          <para>Configures the root file system and its file system
+          type and mount options, as well as whether it shall be
+          mounted read-only or read-write initially. For details,
+          see
+          <citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>mount.usr=</varname></term>
+        <term><varname>mount.usrfstype=</varname></term>
+        <term><varname>mount.usrflags=</varname></term>
+
+        <listitem>
+          <para>Configures the /usr file system (if required) and
+          its file system type and mount options. For details, see
+          <citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>veritytab=</varname></term>
+        <term><varname>rd.veritytab=</varname></term>
+        <term><varname>roothash=</varname></term>
+        <term><varname>systemd.verity=</varname></term>
+        <term><varname>rd.systemd.verity=</varname></term>
+        <term><varname>systemd.verity_root_data=</varname></term>
+        <term><varname>systemd.verity_root_hash=</varname></term>
+        <term><varname>systemd.verity.root_options=</varname></term>
+        <term><varname>usrhash=</varname></term>
+        <term><varname>systemd.verity_usr_data=</varname></term>
+        <term><varname>systemd.verity_usr_hash=</varname></term>
+        <term><varname>systemd.verity_usr_options=</varname></term>
+        <listitem>
+          <para>Configures the integrity protection root hash for the root and <filename>/usr</filename> file systems, and other related
+          parameters. For details, see
+          <citerefentry><refentrytitle>systemd-veritysetup-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>systemd.getty_auto=</varname></term>
+
+        <listitem>
+          <para>Configures whether the <filename>serial-getty@.service</filename> will run.
+          For details, see
+          <citerefentry><refentrytitle>systemd-getty-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>systemd.gpt_auto=</varname></term>
+        <term><varname>rd.systemd.gpt_auto=</varname></term>
+
+        <listitem>
+          <para>Configures whether GPT based partition auto-discovery
+          shall be attempted. For details, see
+          <citerefentry><refentrytitle>systemd-gpt-auto-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>systemd.default_timeout_start_sec=</varname></term>
+
+        <listitem>
+          <para>Overrides the default start job timeout <varname>DefaultTimeoutStartSec=</varname> at
+          boot. For details, see
+          <citerefentry><refentrytitle>systemd-system.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>systemd.watchdog_device=</varname></term>
+
+        <listitem>
+          <para>Overrides the watchdog device path <varname>WatchdogDevice=</varname>. For details, see
+          <citerefentry><refentrytitle>systemd-system.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>systemd.watchdog_sec=</varname></term>
+
+        <listitem>
+          <para>Overrides the watchdog timeout settings otherwise configured with
+          <varname>RuntimeWatchdog=</varname>, <varname>RebootWatchdog=</varname> and
+          <varname>KExecWatchdogSec=</varname>. Takes a time value (if no unit is specified, seconds is the
+          implicitly assumed time unit) or the special strings <literal>off</literal> or
+          <literal>default</literal>. For details, see
+          <citerefentry><refentrytitle>systemd-system.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>systemd.watchdog_pre_sec=</varname></term>
+
+        <listitem>
+          <para>Overrides the watchdog pre-timeout settings otherwise configured with
+          <varname>RuntimeWatchdogPreSec=</varname>. Takes a time value (if no unit is specified, seconds is the
+          implicitly assumed time unit) or the special strings <literal>off</literal> or
+          <literal>default</literal>. For details, see
+          <citerefentry><refentrytitle>systemd-system.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>systemd.watchdog_pretimeout_governor=</varname></term>
+
+        <listitem>
+          <para>Overrides the watchdog pre-timeout settings otherwise configured with
+          <varname>RuntimeWatchdogPreGovernor=</varname>. Takes a string value. For details, see
+          <citerefentry><refentrytitle>systemd-system.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>systemd.cpu_affinity=</varname></term>
+
+        <listitem>
+          <para>Overrides the CPU affinity mask for the service manager and the default for all child
+          processes it forks. This takes precedence over <varname>CPUAffinity=</varname>, see
+          <citerefentry><refentrytitle>systemd-system.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+          for details.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>modules_load=</varname></term>
+        <term><varname>rd.modules_load=</varname></term>
+
+        <listitem>
+          <para>Load a specific kernel module early at boot. For
+          details, see
+          <citerefentry><refentrytitle>systemd-modules-load.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>resume=</varname></term>
+        <term><varname>resumeflags=</varname></term>
+
+        <listitem>
+          <para>Enables resume from hibernation using the specified
+          device and mount options. All
+          <citerefentry project='man-pages'><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry>-like
+          paths are supported. For details, see
+          <citerefentry><refentrytitle>systemd-hibernate-resume-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>systemd.firstboot=</varname></term>
+
+        <listitem><para>Takes a boolean argument, defaults to on. If off,
+        <citerefentry><refentrytitle>systemd-firstboot.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+        will not query the user for basic system settings, even if the system boots up for the first time and
+        the relevant settings are not initialized yet. Not to be confused with
+        <varname>systemd.condition-first-boot=</varname> (see below), which overrides the result of the
+        <varname>ConditionFirstBoot=</varname> unit file condition, and thus controls more than just
+        <filename>systemd-firstboot.service</filename> behaviour.</para></listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>systemd.condition-needs-update=</varname></term>
+
+        <listitem><para>Takes a boolean argument. If specified, overrides the result of
+        <varname>ConditionNeedsUpdate=</varname> unit condition checks. See
+        <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry> for
+        details.</para></listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>systemd.condition-first-boot=</varname></term>
+
+        <listitem><para>Takes a boolean argument. If specified, overrides the result of
+        <varname>ConditionFirstBoot=</varname> unit condition checks. See
+        <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry> for
+        details. Not to be confused with <varname>systemd.firstboot=</varname> which only controls behaviour
+        of the <filename>systemd-firstboot.service</filename> system service but has no effect on the
+        condition check (see above).</para></listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>systemd.clock-usec=</varname></term>
+
+        <listitem><para>Takes a decimal, numeric timestamp in µs since January 1st 1970, 00:00am, to set the
+        system clock to. The system time is set to the specified timestamp early during boot. It is not
+        propagated to the hardware clock (RTC).</para></listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>systemd.random-seed=</varname></term>
+
+        <listitem><para>Takes a base64 encoded random seed value to credit with full entropy to the kernel's
+        random pool during early service manager initialization. This option is useful in testing
+        environments where delays due to random pool initialization in entropy starved virtual machines shall
+        be avoided.</para>
+
+        <para>Note that if this option is used the seed is accessible to unprivileged programs from
+        <filename>/proc/cmdline</filename>. This option is hence a security risk when used outside of test
+        systems, since the (possibly) only seed used for initialization of the kernel's entropy pool might be
+        easily acquired by unprivileged programs.</para>
+
+        <para>It is recommended to pass 512 bytes of randomized data (as that matches the Linux kernel pool
+        size), which may be generated with a command like the following:</para>
+
+        <programlisting>dd if=/dev/urandom bs=512 count=1 status=none | base64 -w 0</programlisting>
+
+        <para>Again: do not use this option outside of testing environments, it's a security risk elsewhere,
+        as secret key material derived from the entropy pool can possibly be reconstructed by unprivileged
+        programs.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>systemd.hostname=</varname></term>
+
+        <listitem><para>Accepts a hostname to set during early boot. If specified takes precedence over what
+        is set in <filename>/etc/hostname</filename>. Note that this does not bar later runtime changes to
+        the hostname, it simply controls the initial hostname set during early boot.</para></listitem>
+      </varlistentry>
+    </variablelist>
+  </refsect1>
+
+  <refsect1>
+      <title>History</title>
+
+      <variablelist>
+        <varlistentry>
+          <term>systemd 252</term>
+          <listitem><para>Kernel command-line arguments <varname>systemd.unified_cgroup_hierarchy</varname>
+          and <varname>systemd.legacy_systemd_cgroup_controller</varname> were deprecated. Please switch to
+          the unified cgroup hierarchy.</para></listitem>
+        </varlistentry>
+      </variablelist>
+  </refsect1>
+
+  <refsect1>
+      <title>See Also</title>
+      <para>
+        <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+        <citerefentry><refentrytitle>systemd-system.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+        <citerefentry project='man-pages'><refentrytitle>bootparam</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
+        <citerefentry project='man-pages'><refentrytitle>dracut.cmdline</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
+        <citerefentry><refentrytitle>systemd-debug-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+        <citerefentry><refentrytitle>systemd-fsck@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+        <citerefentry><refentrytitle>systemd-quotacheck.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+        <citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+        <citerefentry><refentrytitle>systemd-vconsole-setup.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+        <citerefentry><refentrytitle>systemd-udevd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+        <citerefentry project='die-net'><refentrytitle>plymouth</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+        <citerefentry><refentrytitle>systemd-cryptsetup-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+        <citerefentry><refentrytitle>systemd-veritysetup-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+        <citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+        <citerefentry><refentrytitle>systemd-getty-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+        <citerefentry><refentrytitle>systemd-gpt-auto-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+        <citerefentry><refentrytitle>systemd-volatile-root.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+        <citerefentry><refentrytitle>systemd-modules-load.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+        <citerefentry><refentrytitle>systemd-backlight@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+        <citerefentry><refentrytitle>systemd-rfkill.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+        <citerefentry><refentrytitle>systemd-hibernate-resume-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+        <citerefentry><refentrytitle>systemd-firstboot.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+        <citerefentry><refentrytitle>bootctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
+      </para>
+  </refsect1>
+
+</refentry>