lfs/chapter08/kmod.xml

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<!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
  "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
  <!ENTITY % general-entities SYSTEM "../general.ent">
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<sect1 id="ch-system-kmod" role="wrap">
  <?dbhtml filename="kmod.html"?>

  <sect1info condition="script">
    <productname>kmod</productname>
    <productnumber>&kmod-version;</productnumber>
    <address>&kmod-url;</address>
  </sect1info>

  <title>Kmod-&kmod-version;</title>

  <indexterm zone="ch-system-kmod">
    <primary sortas="a-Kmod">Kmod</primary>
  </indexterm>

  <sect2 role="package">
    <title/>

    <para>The Kmod package contains libraries and utilities for loading kernel
    modules</para>

    <segmentedlist>
      <segtitle>&buildtime;</segtitle>
      <segtitle>&diskspace;</segtitle>

      <seglistitem>
        <seg>&kmod-fin-sbu;</seg>
        <seg>&kmod-fin-du;</seg>
      </seglistitem>
    </segmentedlist>

  </sect2>

  <sect2 role="installation">
    <title>Installation of Kmod</title>

    <para>Prepare Kmod for compilation:</para>

<screen><userinput remap="configure">./configure --prefix=/usr     \
            --sysconfdir=/etc \
            --with-openssl    \
            --with-xz         \
            --with-zstd       \
            --with-zlib       \
            --disable-manpages</userinput></screen>

    <variablelist>
      <title>The meaning of the configure options:</title>

      <varlistentry>
        <term>
          <parameter>--with-openssl</parameter>
        </term>
        <listitem>
          <para>This option enables Kmod to handle PKCS7 signatures for
          kernel modules.</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>
          <parameter>--with-xz</parameter>,
          <parameter>--with-zlib</parameter>, and
          <parameter>--with-zstd</parameter>
        </term>
        <listitem>
          <para>These options enable Kmod to handle compressed kernel modules.</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>
          <parameter>--disable-manpages</parameter>
        </term>
        <listitem>
          <para>This option disables generating the man pages which
          requires an external program.</para>
        </listitem>
      </varlistentry>

    </variablelist>

    <para>Compile the package:</para>

<screen><userinput remap="make">make</userinput></screen>

    <para>The test suite of this package requires raw kernel headers
    (not the <quote>sanitized</quote> kernel headers installed earlier),
    which are beyond the scope of LFS.</para>

    <para>Install the package and recreate some symlinks for
    compatibility with Module-Init-Tools (the package that previously handled
    Linux kernel modules).  The building system will create all these
    symlinks in <filename class='directory'>/usr/bin</filename>, but we
    only want <command>lsmod</command> there and all other symlinks in
    <filename class='directory'>/usr/sbin</filename> instead:</para>

<screen><userinput remap="install">make install

for target in depmod insmod modinfo modprobe rmmod; do
  ln -sfv ../bin/kmod /usr/sbin/$target
  rm -fv /usr/bin/$target
done</userinput></screen>

  </sect2>

  <sect2 id="contents-kmod" role="content">
    <title>Contents of Kmod</title>

    <segmentedlist>
      <segtitle>Installed programs</segtitle>
      <segtitle>Installed library</segtitle>

      <seglistitem>
        <seg>depmod (link to kmod), insmod (link to kmod), kmod,
        lsmod (link to kmod), modinfo (link to kmod), modprobe (link to kmod),
        and rmmod (link to kmod)</seg>
        <seg>libkmod.so</seg>
      </seglistitem>
    </segmentedlist>

    <variablelist>
      <bridgehead renderas="sect3">Short Descriptions</bridgehead>
      <?dbfo list-presentation="list"?>
      <?dbhtml list-presentation="table"?>

      <varlistentry id="depmod">
        <term><command>depmod</command></term>
        <listitem>
          <para>Creates a dependency file based on the symbols it finds in the
          existing set of modules; this dependency file is used by
          <command>modprobe</command> to automatically load the required
          modules</para>
          <indexterm zone="ch-system-kmod depmod">
            <primary sortas="b-depmod">depmod</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="insmod">
        <term><command>insmod</command></term>
        <listitem>
          <para>Installs a loadable module in the running kernel</para>
          <indexterm zone="ch-system-kmod insmod">
            <primary sortas="b-insmod">insmod</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="kmod">
        <term><command>kmod</command></term>
        <listitem>
          <para>Loads and unloads kernel modules</para>
          <indexterm zone="ch-system-kmod kmod">
            <primary sortas="b-kmod">kmod</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="lsmod">
        <term><command>lsmod</command></term>
        <listitem>
          <para>Lists currently loaded modules</para>
          <indexterm zone="ch-system-kmod lsmod">
            <primary sortas="b-lsmod">lsmod</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="modinfo">
        <term><command>modinfo</command></term>
        <listitem>
          <para>Examines an object file associated with a kernel module and
          displays any information that it can glean</para>
          <indexterm zone="ch-system-kmod modinfo">
            <primary sortas="b-modinfo">modinfo</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="modprobe">
        <term><command>modprobe</command></term>
        <listitem>
          <para>Uses a dependency file, created by
          <command>depmod</command>, to automatically load relevant modules</para>
          <indexterm zone="ch-system-kmod modprobe">
            <primary sortas="b-modprobe">modprobe</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="rmmod">
        <term><command>rmmod</command></term>
        <listitem>
          <para>Unloads modules from the running kernel</para>
          <indexterm zone="ch-system-kmod rmmod">
            <primary sortas="b-rmmod">rmmod</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="libkmod">
        <term><filename class="libraryfile">libkmod</filename></term>
        <listitem>
          <para>This library is used by other programs to load and unload kernel
           modules</para>
          <indexterm zone="ch-system-kmod">
            <primary sortas="c-libkmod">libkmod</primary>
          </indexterm>
        </listitem>
      </varlistentry>

    </variablelist>

  </sect2>

</sect1>