xref: /aosp_15_r20/external/kmod/man/modprobe.d.5.xml (revision cc4ad7da8cefe208cb129ac2aa9a357c7c72deb2)
1<?xml version="1.0"?>
2<!--*-nxml-*-->
3<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
4<refentry id="modprobe.d">
5  <refentryinfo>
6    <title>modprobe.d</title>
7    <productname>kmod</productname>
8
9    <authorgroup>
10      <author>
11        <contrib>Developer</contrib>
12        <firstname>Jon</firstname>
13        <surname>Masters</surname>
14        <email>[email protected]</email>
15      </author>
16      <author>
17        <contrib>Developer</contrib>
18        <firstname>Robby</firstname>
19        <surname>Workman</surname>
20        <email>[email protected]</email>
21      </author>
22      <author>
23        <contrib>Developer</contrib>
24        <firstname>Lucas</firstname>
25        <surname>De Marchi</surname>
26        <email>[email protected]</email>
27      </author>
28    </authorgroup>
29  </refentryinfo>
30
31
32  <refmeta>
33    <refentrytitle>modprobe.d</refentrytitle>
34    <manvolnum>5</manvolnum>
35  </refmeta>
36
37  <refnamediv>
38    <refname>modprobe.d</refname>
39    <refpurpose>Configuration directory for modprobe</refpurpose>
40  </refnamediv>
41
42  <refsynopsisdiv>
43    <para><filename>/lib/modprobe.d/*.conf</filename></para>
44    <para><filename>@DISTCONFDIR@/modprobe.d/*.conf</filename></para>
45    <para><filename>/usr/local/lib/modprobe.d/*.conf</filename></para>
46    <para><filename>/run/modprobe.d/*.conf</filename></para>
47    <para><filename>/etc/modprobe.d/*.conf</filename></para>
48  </refsynopsisdiv>
49
50  <refsect1><title>DESCRIPTION</title>
51    <para>Because the <command>modprobe</command> command can add or
52      remove more than one module, due to modules having dependencies,
53      we need a method of specifying what options are to be used with
54      those modules.  All files underneath the
55      <filename>/etc/modprobe.d</filename> directory which end with the
56      <filename>.conf</filename> extension specify those options as
57      required.  They can also be used to create convenient aliases:
58      alternate names for a module, or they can override the normal
59      <command>modprobe</command> behavior altogether for those with
60      special requirements (such as inserting more than one module).
61    </para>
62    <para>
63      Note that module and alias names (like other module names) can
64      have - or _ in them: both are interchangeable throughout all the
65      module commands as underscore conversion happens automatically.
66    </para>
67    <para>
68      The format of files under <filename>modprobe.d</filename> is
69      simple: one command per line, with blank lines and lines starting
70      with '#' ignored (useful for adding comments).  A '\' at the end
71      of a line causes it to continue on the next line, which makes the
72      file a bit neater.
73    </para>
74  </refsect1>
75
76  <refsect1><title>COMMANDS</title>
77    <variablelist>
78      <varlistentry>
79        <term>alias <replaceable>wildcard</replaceable> <replaceable>modulename</replaceable>
80        </term>
81        <listitem>
82          <para>
83            This allows you to give alternate names for a module.  For example:
84            "alias my-mod really_long_modulename" means you can use "modprobe
85            my-mod" instead of "modprobe really_long_modulename".  You can also
86            use shell-style wildcards, so "alias my-mod*
87            really_long_modulename" means that "modprobe my-mod-something" has
88            the same effect.  You can't have aliases to other aliases (that way
89            lies madness), but aliases can have options, which will be added to
90            any other options.
91          </para>
92          <para>
93            Note that modules can also contain their own aliases, which you can
94            see using <command>modinfo</command>.  These aliases are used as a
95            last resort (ie. if there is no real module,
96            <command>install</command>, <command>remove</command>, or
97            <command>alias</command> command in the configuration).
98          </para>
99        </listitem>
100      </varlistentry>
101      <varlistentry>
102        <term>blacklist <replaceable>modulename</replaceable>
103        </term>
104        <listitem>
105          <para>
106            Modules can contain their own aliases: usually these are aliases
107            describing the devices they support, such as "pci:123...".  These
108            "internal" aliases can be overridden by normal "alias" keywords,
109            but there are cases where two or more modules both support the same
110            devices, or a module invalidly claims to support a device that it
111            does not: the <command>blacklist</command> keyword indicates that
112            all of that particular module's internal aliases are to be ignored.
113          </para>
114        </listitem>
115      </varlistentry>
116      <varlistentry>
117        <term>install <replaceable>modulename</replaceable> <replaceable>command...</replaceable>
118        </term>
119        <listitem>
120          <para>
121            This command instructs <command>modprobe</command> to run your
122            command instead of inserting the module in the kernel as normal.
123            The command can be any shell command: this allows you to do any
124            kind of complex processing you might wish.  For example, if the
125            module "fred" works better with the module "barney" already
126            installed (but it doesn't depend on it, so
127            <command>modprobe</command> won't automatically load it), you could
128            say "install fred /sbin/modprobe barney; /sbin/modprobe
129            --ignore-install fred", which would do what you wanted.  Note the
130            <option>--ignore-install</option>, which stops the second
131            <command>modprobe</command> from running the same
132            <command>install</command> command again.  See also
133            <command>remove</command> below.  </para> <para>The long term
134            future of this command as a solution to the problem of providing
135            additional module dependencies is not assured and it is intended to
136            replace this command with a warning about its eventual removal or
137            deprecation at some point in a future release. Its use complicates
138            the automated determination of module dependencies by distribution
139            utilities, such as mkinitrd (because these now need to somehow
140            interpret what the <command>install</command> commands might be
141            doing.  In a perfect world, modules would provide all dependency
142            information without the use of this command and work is underway to
143            implement soft dependency support within the Linux kernel.  </para>
144          <para> If you use the string "$CMDLINE_OPTS" in the command, it will
145            be replaced by any options specified on the modprobe command line.
146            This can be useful because users expect "modprobe fred opt=1" to
147            pass the "opt=1" arg to the module, even if there's an install
148            command in the configuration file.  So our above example becomes
149            "install fred /sbin/modprobe barney; /sbin/modprobe
150            --ignore-install fred $CMDLINE_OPTS"
151          </para>
152        </listitem>
153      </varlistentry>
154      <varlistentry>
155        <term>options <replaceable>modulename</replaceable> <replaceable>option...</replaceable>
156        </term>
157        <listitem>
158          <para>
159            This command allows you to add options to the module
160            <replaceable>modulename</replaceable> (which might be an
161            alias) every time it is inserted into the kernel: whether
162            directly (using <command>modprobe </command>
163            <replaceable>modulename</replaceable>) or because the
164            module being inserted depends on this module.
165          </para>
166          <para>
167            All options are added together: they can come from an
168            <command>option</command> for the module itself, for an
169            alias, and on the command line.
170          </para>
171        </listitem>
172      </varlistentry>
173      <varlistentry>
174        <term>remove <replaceable>modulename</replaceable> <replaceable>command...</replaceable>
175        </term>
176        <listitem>
177          <para>
178            This is similar to the <command>install</command> command
179            above, except it is invoked when "modprobe -r" is run.
180          </para>
181        </listitem>
182      </varlistentry>
183      <varlistentry>
184        <term>softdep <replaceable>modulename</replaceable> pre: <replaceable>modules...</replaceable> post: <replaceable>modules...</replaceable>
185        </term>
186        <listitem>
187          <para>
188            The <command>softdep</command> command allows you to specify soft,
189            or optional, module dependencies. <replaceable>modulename</replaceable>
190            can be used without these optional modules installed, but usually with
191            some features missing. For example, a driver for a storage HBA might
192            require another module be loaded in order to use management features.
193          </para>
194          <para>
195            pre-deps and post-deps modules are lists of names and/or aliases of other
196            modules that modprobe will attempt to install (or remove) in order
197            before and after the main module given in the
198            <replaceable>modulename</replaceable> argument.
199          </para>
200          <para>
201            Example: Assume "softdep c pre: a b post: d e" is provided in the
202            configuration. Running "modprobe c" is now equivalent to
203            "modprobe a b c d e" without the softdep.
204            Flags such as --use-blacklist are applied to all the specified
205            modules, while module parameters only apply to module c.
206          </para>
207          <para>
208            Note: if there are <command>install</command> or
209            <command>remove</command> commands with the same
210            <replaceable>modulename</replaceable> argument,
211            <command>softdep</command> takes precedence.
212          </para>
213        </listitem>
214      </varlistentry>
215    </variablelist>
216  </refsect1>
217  <refsect1><title>COMPATIBILITY</title>
218    <para>
219      A future version of kmod will come with a strong warning to avoid use of
220      the <command>install</command> as explained above.  This will happen once
221      support for soft dependencies in the kernel is complete.  That support
222      will complement the existing softdep support within this utility by
223      providing such dependencies directly within the modules.
224    </para>
225  </refsect1>
226  <refsect1><title>COPYRIGHT</title>
227    <para>
228      This manual page originally Copyright 2004, Rusty Russell, IBM
229      Corporation. Maintained by Jon Masters and others.
230    </para>
231  </refsect1>
232  <refsect1><title>SEE ALSO</title>
233    <para><citerefentry>
234        <refentrytitle>modprobe</refentrytitle><manvolnum>8</manvolnum>
235      </citerefentry>,
236      <citerefentry>
237        <refentrytitle>modules.dep</refentrytitle><manvolnum>5</manvolnum>
238      </citerefentry>
239    </para>
240  </refsect1>
241</refentry>
242