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diff --git a/man/kernel-install.xml b/man/kernel-install.xml new file mode 100644 index 0000000..b8ea2b1 --- /dev/null +++ b/man/kernel-install.xml @@ -0,0 +1,392 @@ +<?xml version='1.0'?> +<!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-install" conditional='ENABLE_KERNEL_INSTALL' + xmlns:xi="http://www.w3.org/2001/XInclude"> + + <refentryinfo> + <title>kernel-install</title> + <productname>systemd</productname> + </refentryinfo> + + <refmeta> + <refentrytitle>kernel-install</refentrytitle> + <manvolnum>8</manvolnum> + </refmeta> + + <refnamediv> + <refname>kernel-install</refname> + <refpurpose>Add and remove kernel and initrd images to and from /boot</refpurpose> + </refnamediv> + + <refsynopsisdiv> + <cmdsynopsis> + <command>kernel-install</command> + <arg choice="opt" rep="repeat">OPTIONS</arg> + <arg choice="plain">COMMAND</arg> + <arg choice="plain"><replaceable>KERNEL-VERSION</replaceable></arg> + <arg choice="plain"><replaceable>KERNEL-IMAGE</replaceable></arg> + <arg choice="opt" rep="repeat"><replaceable>INITRD-FILE</replaceable></arg> + </cmdsynopsis> + </refsynopsisdiv> + + <refsect1> + <title>Description</title> + <para><command>kernel-install</command> is used to install and remove kernel and initrd images + <footnote> + <para>Nowadays actually CPIO archives used as an "initramfs", rather than "initrd". See + <citerefentry><refentrytitle>bootup</refentrytitle><manvolnum>7</manvolnum></citerefentry> for an + explanation.</para> + </footnote> + to and from the boot loader partition, referred to as <varname>$BOOT</varname> here. It will usually be + one of <filename>/boot/</filename>, <filename>/efi/</filename>, or <filename>/boot/efi/</filename>, see + below.</para> + + <para><command>kernel-install</command> will run the executable files ("plugins") located in the + directory <filename>/usr/lib/kernel/install.d/</filename> and the local administration directory + <filename>/etc/kernel/install.d/</filename>. All files are collectively sorted and executed in lexical + order, regardless of the directory in which they live. However, files with identical filenames replace + each other. Files in <filename>/etc/kernel/install.d/</filename> take precedence over files with the + same name in <filename>/usr/lib/kernel/install.d/</filename>. This can be used to override a + system-supplied executables with a local file if needed; a symbolic link in + <filename>/etc/kernel/install.d/</filename> with the same name as an executable in + <filename>/usr/lib/kernel/install.d/</filename>, pointing to <filename>/dev/null</filename>, disables the + executable entirely. Executables must have the extension <literal>.install</literal>; other extensions + are ignored.</para> + + <para>An executable placed in these directories should return <constant>0</constant> on success. It may + also return <constant>77</constant> to cause the whole operation to terminate (executables later in + lexical order will be skipped).</para> + </refsect1> + + <refsect1> + <title>Commands</title> + <para>The following commands are understood:</para> + <variablelist> + <varlistentry> + <term><command>add <replaceable>KERNEL-VERSION</replaceable> <replaceable>KERNEL-IMAGE</replaceable> [<replaceable>INITRD-FILE</replaceable> ...]</command></term> + <listitem> + <para>This command expects a kernel version string and a path to a kernel image file as arguments. + Optionally, one or more initrd images may be specified as well (note that plugins might generate + additional ones). <command>kernel-install</command> calls the executable files from + <filename>/usr/lib/kernel/install.d/*.install</filename> and + <filename>/etc/kernel/install.d/*.install</filename> (i.e. the plugins) with the following + arguments:</para> + + <programlisting>add <replaceable>KERNEL-VERSION</replaceable> <filename>$BOOT/<replaceable>ENTRY-TOKEN</replaceable>/<replaceable>KERNEL-VERSION</replaceable>/</filename> <replaceable>KERNEL-IMAGE</replaceable> [<replaceable>INITRD-FILE</replaceable> ...]</programlisting> + + <para>The third argument directly refers to the path where to place kernel images, initrd + images and other resources for <ulink url="https://systemd.io/BOOT_LOADER_SPECIFICATION">Boot + Loader Specification</ulink> Type #1 entries (the "entry directory"). If other boot loader schemes + are used the parameter may be ignored. The <replaceable>ENTRY-TOKEN</replaceable> string is + typically the machine ID and is supposed to identify the local installation on the system. For + details see below.</para> + + <para>Two default plugins execute the following operations in this case:</para> + + <itemizedlist> + <listitem><para><command>kernel-install</command> creates + <filename>$BOOT/<replaceable>ENTRY-TOKEN</replaceable>/<replaceable>KERNEL-VERSION</replaceable></filename>, + if enabled (see <varname>$KERNEL_INSTALL_LAYOUT</varname>).</para></listitem> + + <listitem><para><filename>50-depmod.install</filename> runs + <citerefentry project='man-pages'><refentrytitle>depmod</refentrytitle><manvolnum>8</manvolnum></citerefentry> for the + <replaceable>KERNEL-VERSION</replaceable>.</para></listitem> + + <listitem><para><filename>90-loaderentry.install</filename> copies + <replaceable>KERNEL-IMAGE</replaceable> to + <filename>$BOOT/<replaceable>ENTRY-TOKEN</replaceable>/<replaceable>KERNEL-VERSION</replaceable>/linux</filename>. + If <replaceable>INITRD-FILE</replaceable>s are provided, it also copies them to + <filename>$BOOT/<replaceable>ENTRY-TOKEN</replaceable>/<replaceable>KERNEL_VERSION</replaceable>/<replaceable>INITRD-FILE</replaceable></filename>. + It also creates a boot loader entry according to the <ulink + url="https://systemd.io/BOOT_LOADER_SPECIFICATION">Boot Loader Specification</ulink> (Type #1) in + <filename>$BOOT/loader/entries/<replaceable>ENTRY-TOKEN</replaceable>-<replaceable>KERNEL-VERSION</replaceable>.conf</filename>. + The title of the entry is the <replaceable>PRETTY_NAME</replaceable> parameter specified in + <filename>/etc/os-release</filename> or <filename>/usr/lib/os-release</filename> (if the former + is missing), or "Linux <replaceable>KERNEL-VERSION</replaceable>", if unset.</para> + + <para>If <varname>$KERNEL_INSTALL_LAYOUT</varname> is not "bls", this plugin does nothing.</para></listitem> + </itemizedlist> + </listitem> + </varlistentry> + <varlistentry> + <term><command>remove <replaceable>KERNEL-VERSION</replaceable></command></term> + <listitem> + <para>This command expects a kernel version string as single argument. This calls executables from + <filename>/usr/lib/kernel/install.d/*.install</filename> and + <filename>/etc/kernel/install.d/*.install</filename> with the following arguments: + </para> + + <programlisting>remove <replaceable>KERNEL-VERSION</replaceable> <filename>$BOOT/<replaceable>ENTRY-TOKEN</replaceable>/<replaceable>KERNEL-VERSION</replaceable>/</filename></programlisting> + + <para>Afterwards, <command>kernel-install</command> removes the entry directory + <filename>$BOOT/<replaceable>ENTRY-TOKEN</replaceable>/<replaceable>KERNEL-VERSION</replaceable>/</filename> + and its contents, if it exists.</para> + + <para>Two default plugins execute the following operations in this case:</para> + + <itemizedlist> + <listitem><para><filename>50-depmod.install</filename> removes the files generated by <command>depmod</command> for this kernel again.</para></listitem> + + <listitem><para><filename>90-loaderentry.install</filename> removes the file + <filename>$BOOT/loader/entries/<replaceable>ENTRY-TOKEN</replaceable>-<replaceable>KERNEL-VERSION</replaceable>.conf</filename>.</para></listitem> + </itemizedlist> + </listitem> + </varlistentry> + <varlistentry> + <term><command>inspect</command></term> + <listitem> + <para>Shows the various paths and parameters configured or auto-detected. In particular shows the + values of the various <varname>$KERNEL_INSTALL_*</varname> environment variables listed + below.</para> + </listitem> + </varlistentry> + + </variablelist> + </refsect1> + + <refsect1> + <title>The <varname>$BOOT</varname> partition</title> + + <para>The partition where the kernels and <ulink url="https://systemd.io/BOOT_LOADER_SPECIFICATION">Boot + Loader Specification</ulink> snippets are located is called <varname>$BOOT</varname>. + <command>kernel-install</command> determines the location of this partition by checking + <filename>/efi/</filename>, <filename>/boot/</filename>, and <filename>/boot/efi/</filename> in turn. The + first location where <filename>$BOOT/loader/entries/</filename> or + <filename>$BOOT/<replaceable>ENTRY-TOKEN</replaceable>/</filename> exists is used.</para> + </refsect1> + + <refsect1> + <title>Options</title> + <para>The following options are understood:</para> + + <variablelist> + <varlistentry> + <term><option>-v</option></term> + <term><option>--verbose</option></term> + <listitem> + <para>Output additional information about operations being performed.</para> + </listitem> + </varlistentry> + + <xi:include href="standard-options.xml" xpointer="help" /> + <xi:include href="standard-options.xml" xpointer="version" /> + </variablelist> + </refsect1> + + <refsect1> + <title>Environment variables</title> + + <refsect2> + <title>Environment variables exported for plugins</title> + + <para>If <option>--verbose</option> is used, <varname>$KERNEL_INSTALL_VERBOSE=1</varname> will be + exported for plugins. They may output additional logs in this case.</para> + + <para><varname>$KERNEL_INSTALL_MACHINE_ID</varname> is set for the plugins to the desired machine-id to + use. It's always a 128-bit ID. Normally it's read from <filename>/etc/machine-id</filename>, but it can + also be overridden via <varname>$MACHINE_ID</varname> (see below). If not specified via these methods a + fallback value will generated by <command>kernel-install</command>, and used only for a single + invocation.</para> + + <para><varname>$KERNEL_INSTALL_ENTRY_TOKEN</varname> is set for the plugins to the desired entry + "token" to use. It's an identifier that shall be used to identify the local installation, and is often + the machine ID, i.e. same as <varname>$KERNEL_INSTALL_MACHINE_ID</varname>, but might also be a + different type of identifier, for example a fixed string or the <varname>ID=</varname>, + <varname>IMAGE_ID=</varname> values from <filename>/etc/os-release</filename>. The string passed here + will be used to name Boot Loader Specification entries, or the directories the kernel image and initial + RAM disk images are placed into.</para> + + <para>Note that while <varname>$KERNEL_INSTALL_ENTRY_TOKEN</varname> and + <varname>$KERNEL_INSTALL_MACHINE_ID</varname> are often set to the same value, the latter is guaranteed + to be a valid 32 character ID in lowercase hexadecimals while the former can be any short string. The + entry token to use is read from <filename>/etc/kernel/entry-token</filename>, if it exists. Otherwise a + few possible candidates below <varname>$BOOT</varname> are checked for Boot Loader Specification Type 1 + entry directories, and if found the entry token is derived from that. If that is not successful, + <varname>$KERNEL_INSTALL_MACHINE_ID</varname> is used as fallback.</para> + + <para><varname>$KERNEL_INSTALL_BOOT_ROOT</varname> is set for the plugins to the absolute path of the + root directory (mount point, usually) of the hierarchy where boot loader entries, kernel images, and + associated resources should be placed. This usually is the path where the XBOOTLDR partition or the ESP + (EFI System Partition) are mounted, and also conceptually referred to as <varname>$BOOT</varname>. Can + be overridden by setting <varname>$BOOT_ROOT</varname> (see below).</para> + + <para><varname>$KERNEL_INSTALL_LAYOUT=bls|other|...</varname> is set for the plugins to specify the + installation layout. Defaults to <option>bls</option> if + <filename>$BOOT/<replaceable>ENTRY-TOKEN</replaceable></filename> exists, or <option>other</option> + otherwise. Additional layout names may be defined by convention. If a plugin uses a special layout, + it's encouraged to declare its own layout name and configure <varname>layout=</varname> in + <filename>install.conf</filename> upon initial installation. The following values are currently + understood:</para> + + <variablelist> + <varlistentry> + <term>bls</term> + <listitem> + <para>Standard <ulink url="https://systemd.io/BOOT_LOADER_SPECIFICATION">Boot Loader + Specification</ulink> Type #1 layout, compatible with + <citerefentry><refentrytitle>systemd-boot</refentrytitle><manvolnum>7</manvolnum></citerefentry>: + entries in + <filename>$BOOT/loader/entries/<replaceable>ENTRY-TOKEN</replaceable>-<replaceable>KERNEL-VERSION</replaceable>[+<replaceable>TRIES</replaceable>].conf</filename>, + kernel and initrds under + <filename>$BOOT/<replaceable>ENTRY-TOKEN</replaceable>/<replaceable>KERNEL-VERSION</replaceable>/</filename></para> + <para>Implemented by <filename>90-loaderentry.install</filename>.</para> + </listitem> + </varlistentry> + <varlistentry> + <term>other</term> + <listitem> + <para>Some other layout not understood natively by <command>kernel-install</command>.</para> + </listitem> + </varlistentry> + </variablelist> + + <para><varname>$KERNEL_INSTALL_INITRD_GENERATOR</varname> is set for plugins to select the initrd + generator. This may be configured as <varname>initrd_generator=</varname> in + <filename>install.conf</filename>, see below.</para> + + <para><varname>$KERNEL_INSTALL_STAGING_AREA</varname> is set for plugins to a path to a directory. + Plugins may drop files in that directory, and they will be installed as part of the loader entry, based + on the file name and extension.</para> + </refsect2> + + <refsect2> + <title>Environment variables understood by <command>kernel-install</command></title> + + <para><varname>$KERNEL_INSTALL_CONF_ROOT</varname> can be set to override the location of the + configuration files read by <command>kernel-install</command>. When set, + <filename>install.conf</filename>, <filename>entry-token</filename>, and other files will be + read from this directory.</para> + + <para><varname>$KERNEL_INSTALL_PLUGINS</varname> can be set to override the list of plugins executed by + <command>kernel-install</command>. The argument is a whitespace-separated list of paths. + <literal>KERNEL_INSTALL_PLUGINS=:</literal> may be used to prevent any plugins from running. + </para> + + <para><varname>$MACHINE_ID</varname> can be set for <command>kernel-install</command> to override + <varname>$KERNEL_INSTALL_MACHINE_ID</varname>, the machine ID.</para> + + <para><varname>$BOOT_ROOT</varname> can be set for <command>kernel-install</command> to override + <varname>$KERNEL_INSTALL_BOOT_ROOT</varname>, the installation location for boot entries.</para> + + <para>The last two variables may also be set in <filename>install.conf</filename>. Variables set in the + environment take precedence over the values specified in the config file.</para> + </refsect2> + </refsect1> + + <refsect1> + <title>Exit status</title> + <para>If every executable returns 0 or 77, 0 is returned, and a non-zero failure code otherwise.</para> + </refsect1> + + <refsect1> + <title>Files</title> + <variablelist> + <varlistentry> + <term> + <filename>/usr/lib/kernel/install.d/*.install</filename> + <filename>/etc/kernel/install.d/*.install</filename> + </term> + <listitem> + <para>Drop-in files which are executed by kernel-install.</para> + </listitem> + </varlistentry> + <varlistentry> + <term> + <filename>/usr/lib/kernel/cmdline</filename> + <filename>/etc/kernel/cmdline</filename> + <filename>/proc/cmdline</filename> + </term> + <listitem> + <para>Read by <filename>90-loaderentry.install</filename>. The content of the file + <filename>/etc/kernel/cmdline</filename> specifies the kernel command line to use. If that file + does not exist, <filename>/usr/lib/kernel/cmdline</filename> is used. If that also does not + exist, <filename>/proc/cmdline</filename> is used. <varname>$KERNEL_INSTALL_CONF_ROOT</varname> + may be used to override the path.</para> + </listitem> + </varlistentry> + <varlistentry> + <term> + <filename>/etc/kernel/tries</filename> + </term> + <listitem> + <para>Read by <filename>90-loaderentry.install</filename>. If this file exists a numeric value is read from + it and the naming of the generated entry file is slightly altered to include it as + <filename>$BOOT/loader/entries/<replaceable>MACHINE-ID</replaceable>-<replaceable>KERNEL-VERSION</replaceable>+<replaceable>TRIES</replaceable>.conf</filename>. This + is useful for boot loaders such as + <citerefentry><refentrytitle>systemd-boot</refentrytitle><manvolnum>7</manvolnum></citerefentry> which + implement boot attempt counting with a counter embedded in the entry file name. + <varname>$KERNEL_INSTALL_CONF_ROOT</varname> may be used to override the path.</para> + </listitem> + </varlistentry> + <varlistentry> + <term> + <filename>/etc/kernel/entry-token</filename> + </term> + <listitem> + <para>If this file exists it is read and used as "entry token" for this system, i.e. is used for + naming Boot Loader Specification entries, see <varname>$KERNEL_INSTALL_ENTRY_TOKEN</varname> + above for details. <varname>$KERNEL_INSTALL_CONF_ROOT</varname> may be used to override the + path.</para> + </listitem> + </varlistentry> + <varlistentry> + <term> + <filename>/etc/machine-id</filename> + </term> + <listitem> + <para>The content of this file specifies the machine identification + <replaceable>MACHINE-ID</replaceable>.</para> + </listitem> + </varlistentry> + <varlistentry> + <term> + <filename>/etc/os-release</filename> + <filename>/usr/lib/os-release</filename> + </term> + <listitem> + <para>Read by <filename>90-loaderentry.install</filename>. + If available, <varname>PRETTY_NAME=</varname> is read from these files and used as the title of the boot menu entry. + Otherwise, <literal>Linux <replaceable>KERNEL-VERSION</replaceable></literal> will be used.</para> + </listitem> + </varlistentry> + <varlistentry> + <term> + <filename>/usr/lib/kernel/install.conf</filename> + <filename>/etc/kernel/install.conf</filename> + </term> + <listitem> + <para>Configuration options for <command>kernel-install</command>, as a series of + <varname>KEY=</varname><replaceable>VALUE</replaceable> assignments, compatible with shell + syntax, following the same rules as described in + <citerefentry><refentrytitle>os-release</refentrytitle><manvolnum>5</manvolnum></citerefentry>. + <filename>/etc/kernel/install.conf</filename> will be read if present, and + <filename>/usr/lib/kernel/install.conf</filename> otherwise. This file is optional. + <varname>$KERNEL_INSTALL_CONF_ROOT</varname> may be used to override the path. + </para> + + <para>Currently, the following keys are supported: + <varname>MACHINE_ID=</varname>, + <varname>BOOT_ROOT=</varname>, + <varname>layout=</varname>, + <varname>initrd_generator=</varname>. + See the Environment variables section above for details.</para> + </listitem> + </varlistentry> + </variablelist> + </refsect1> + + <refsect1> + <title>See Also</title> + <para> + <citerefentry><refentrytitle>machine-id</refentrytitle><manvolnum>5</manvolnum></citerefentry>, + <citerefentry><refentrytitle>os-release</refentrytitle><manvolnum>5</manvolnum></citerefentry>, + <citerefentry project='man-pages'><refentrytitle>depmod</refentrytitle><manvolnum>8</manvolnum></citerefentry>, + <citerefentry><refentrytitle>systemd-boot</refentrytitle><manvolnum>7</manvolnum></citerefentry>, + <ulink url="https://systemd.io/BOOT_LOADER_SPECIFICATION">Boot Loader Specification</ulink> + </para> + </refsect1> + +</refentry> |