mirror of
https://github.com/systemd/systemd
synced 2024-09-06 16:56:43 +00:00
![Dmitry V. Levin](/assets/img/avatar_default.png)
We seem to have no tool to verify udev rule files. There is a simple udev rules syntax checker in the tree, test/rule-syntax-check.py, but it is too simple to detect less trivial issues not detected by udev, e.g. redundant comparisons (#26593) or labels without references. Such a tool would be beneficial not only for maintaining udev rules distributed along with udev, but also and even more so for maintaining third party udev rules that are more likely to have issues with syntax and semantic correctness. Implement a udev rules syntax and semantics checker in the form of 'udevadm verify [OPTIONS] FILE...' command that is based on udev_rules_parse_file() interface and would apply further checks on top of it in subsequent commits. Resolves: #26606
968 lines
46 KiB
XML
968 lines
46 KiB
XML
<?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="udevadm"
|
||
xmlns:xi="http://www.w3.org/2001/XInclude">
|
||
|
||
<refentryinfo>
|
||
<title>udevadm</title>
|
||
<productname>systemd</productname>
|
||
</refentryinfo>
|
||
|
||
<refmeta>
|
||
<refentrytitle>udevadm</refentrytitle>
|
||
<manvolnum>8</manvolnum>
|
||
</refmeta>
|
||
|
||
<refnamediv>
|
||
<refname>udevadm</refname><refpurpose>udev management tool</refpurpose>
|
||
</refnamediv>
|
||
|
||
<refsynopsisdiv>
|
||
<cmdsynopsis>
|
||
<command>udevadm</command>
|
||
<arg><option>--debug</option></arg>
|
||
<arg><option>--version</option></arg>
|
||
<arg><option>--help</option></arg>
|
||
</cmdsynopsis>
|
||
<cmdsynopsis>
|
||
<command>udevadm info <optional>options</optional> <optional>devpath</optional></command>
|
||
</cmdsynopsis>
|
||
<cmdsynopsis>
|
||
<command>udevadm trigger <optional>options</optional> <optional>devpath</optional></command>
|
||
</cmdsynopsis>
|
||
<cmdsynopsis>
|
||
<command>udevadm settle <optional>options</optional></command>
|
||
</cmdsynopsis>
|
||
<cmdsynopsis>
|
||
<command>udevadm control <replaceable>option</replaceable></command>
|
||
</cmdsynopsis>
|
||
<cmdsynopsis>
|
||
<command>udevadm monitor <optional>options</optional></command>
|
||
</cmdsynopsis>
|
||
<cmdsynopsis>
|
||
<command>udevadm test <optional>options</optional> <replaceable>devpath</replaceable></command>
|
||
</cmdsynopsis>
|
||
<cmdsynopsis>
|
||
<command>udevadm test-builtin <optional>options</optional> <replaceable>command</replaceable> <replaceable>devpath</replaceable></command>
|
||
</cmdsynopsis>
|
||
<cmdsynopsis>
|
||
<command>udevadm verify</command>
|
||
<arg choice="opt" rep="repeat">options</arg>
|
||
<arg choice="plain" rep="repeat"><replaceable>file</replaceable></arg>
|
||
</cmdsynopsis>
|
||
<cmdsynopsis>
|
||
<command>udevadm wait <optional>options</optional> <replaceable>device|syspath</replaceable></command>
|
||
</cmdsynopsis>
|
||
<cmdsynopsis>
|
||
<command>udevadm lock <optional>options</optional> <replaceable>command</replaceable></command>
|
||
</cmdsynopsis>
|
||
</refsynopsisdiv>
|
||
|
||
<refsect1><title>Description</title>
|
||
<para><command>udevadm</command> expects a command and command
|
||
specific options. It controls the runtime behavior of
|
||
<command>systemd-udevd</command>, requests kernel events, manages
|
||
the event queue, and provides simple debugging mechanisms.</para>
|
||
</refsect1>
|
||
|
||
<refsect1><title>Options</title>
|
||
<variablelist>
|
||
<varlistentry>
|
||
<term><option>-d</option></term>
|
||
<term><option>--debug</option></term>
|
||
<listitem>
|
||
<para>Print debug messages to standard error. This option is implied in <command>udevadm test</command> and
|
||
<command>udevadm test-builtin</command> commands.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<xi:include href="standard-options.xml" xpointer="help" />
|
||
</variablelist>
|
||
|
||
<refsect2><title>udevadm info
|
||
<arg choice="opt"><replaceable>options</replaceable></arg>
|
||
<arg choice="opt" rep="repeat"><replaceable>devpath</replaceable>|<replaceable>file</replaceable>|<replaceable>unit</replaceable></arg>
|
||
</title>
|
||
|
||
<para>Query the udev database for device information.</para>
|
||
|
||
<para>Positional arguments should be used to specify one or more devices. Each one may be a device name
|
||
(in which case it must start with <filename>/dev/</filename>), a sys path (in which case it must start
|
||
with <filename>/sys/</filename>), or a systemd device unit name (in which case it must end with
|
||
<literal>.device</literal>, see
|
||
<citerefentry><refentrytitle>systemd.device</refentrytitle><manvolnum>5</manvolnum></citerefentry>).
|
||
</para>
|
||
|
||
<variablelist>
|
||
<varlistentry>
|
||
<term><option>-q</option></term>
|
||
<term><option>--query=<replaceable>TYPE</replaceable></option></term>
|
||
<listitem>
|
||
<para>Query the database for the specified type of device data.
|
||
Valid <replaceable>TYPE</replaceable>s are:
|
||
<constant>name</constant>, <constant>symlink</constant>,
|
||
<constant>path</constant>, <constant>property</constant>,
|
||
<constant>all</constant>.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--property=<replaceable>NAME</replaceable></option></term>
|
||
<listitem>
|
||
<para>When showing device properties using the <option>--query=property</option>
|
||
option, limit display to properties specified in the argument. The argument should
|
||
be a comma-separated list of property names. If not specified, all known properties
|
||
are shown.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>--value</option></term>
|
||
<listitem>
|
||
<para>When showing device properties using the <option>--query=property</option>
|
||
option, print only their values, and skip the property name and <literal>=</literal>.</para>
|
||
<para>Cannot be used together with <option>-x/--export</option> or
|
||
<option>-P/--export-prefix</option>.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-p</option></term>
|
||
<term><option>--path=<replaceable>DEVPATH</replaceable></option></term>
|
||
<listitem>
|
||
<para>The <filename>/sys/</filename> path of the device to query, e.g.
|
||
<filename><optional>/sys/</optional>/class/block/sda</filename>. This option is an alternative to
|
||
the positional argument with a <filename>/sys/</filename> prefix. <command>udevadm info
|
||
--path=/class/block/sda</command> is equivalent to <command>udevadm info
|
||
/sys/class/block/sda</command>.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-n</option></term>
|
||
<term><option>--name=<replaceable>FILE</replaceable></option></term>
|
||
<listitem>
|
||
<para>The name of the device node or a symlink to query,
|
||
e.g. <filename><optional>/dev/</optional>/sda</filename>. This option is an alternative to the
|
||
positional argument with a <filename>/dev/</filename> prefix. <command>udevadm info
|
||
--name=sda</command> is equivalent to <command>udevadm info /dev/sda</command>.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-r</option></term>
|
||
<term><option>--root</option></term>
|
||
<listitem>
|
||
<para>Print absolute paths in <command>name</command> or <command>symlink</command>
|
||
query.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-a</option></term>
|
||
<term><option>--attribute-walk</option></term>
|
||
<listitem>
|
||
<para>Print all sysfs properties of the specified device that can be used
|
||
in udev rules to match the specified device. It prints all devices
|
||
along the chain, up to the root of sysfs that can be used in udev rules.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-t</option></term>
|
||
<term><option>--tree</option></term>
|
||
<listitem>
|
||
<para>Display a sysfs tree. This recursively iterates through the sysfs hierarchy and displays it
|
||
in a tree structure. If a path is specified only the subtree below and its parent directories are
|
||
shown. This will show both device and subsystem items.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-x</option></term>
|
||
<term><option>--export</option></term>
|
||
<listitem>
|
||
<para>Print output as key/value pairs. Values are enclosed in single quotes.
|
||
This takes effects only when <option>--query=property</option> or
|
||
<option>--device-id-of-file=<replaceable>FILE</replaceable></option> is specified.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-P</option></term>
|
||
<term><option>--export-prefix=<replaceable>NAME</replaceable></option></term>
|
||
<listitem>
|
||
<para>Add a prefix to the key name of exported values.
|
||
This implies <option>--export</option>.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-d</option></term>
|
||
<term><option>--device-id-of-file=<replaceable>FILE</replaceable></option></term>
|
||
<listitem>
|
||
<para>Print major/minor numbers of the underlying device, where the file lives on.
|
||
If this is specified, all positional arguments are ignored.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-e</option></term>
|
||
<term><option>--export-db</option></term>
|
||
<listitem>
|
||
<para>Export the content of the udev database.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-c</option></term>
|
||
<term><option>--cleanup-db</option></term>
|
||
<listitem>
|
||
<para>Cleanup the udev database.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-w<optional>SECONDS</optional></option></term>
|
||
<term><option>--wait-for-initialization<optional>=SECONDS</optional></option></term>
|
||
<listitem>
|
||
<para>Wait for device to be initialized. If argument <replaceable>SECONDS</replaceable>
|
||
is not specified, the default is to wait forever.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<xi:include href="standard-options.xml" xpointer="help" />
|
||
<xi:include href="standard-options.xml" xpointer="no-pager" />
|
||
</variablelist>
|
||
|
||
<para>The generated output shows the current device database entry in a terse format. Each line shown
|
||
is prefixed with one of the following characters:</para>
|
||
|
||
<table>
|
||
<title><command>udevadm info</command> output prefixes</title>
|
||
<tgroup cols='2' align='left' colsep='1' rowsep='1'>
|
||
<colspec colname="prefix" />
|
||
<colspec colname="meaning" />
|
||
<thead>
|
||
<row>
|
||
<entry>Prefix</entry>
|
||
<entry>Meaning</entry>
|
||
</row>
|
||
</thead>
|
||
<tbody>
|
||
<row>
|
||
<entry><literal>P:</literal></entry>
|
||
<entry>Device path in <filename>/sys/</filename></entry>
|
||
</row>
|
||
<row>
|
||
<entry><literal>M:</literal></entry>
|
||
<entry>Device name in <filename>/sys/</filename> (i.e. the last component of <literal>P:</literal>)</entry>
|
||
</row>
|
||
<row>
|
||
<entry><literal>R:</literal></entry>
|
||
<entry>Device number in <filename>/sys/</filename> (i.e. the numeric suffix of the last component of <literal>P:</literal>)</entry>
|
||
</row>
|
||
<row>
|
||
<entry><literal>U:</literal></entry>
|
||
<entry>Kernel subsystem</entry>
|
||
</row>
|
||
<row>
|
||
<entry><literal>T:</literal></entry>
|
||
<entry>Kernel device type within subsystem</entry>
|
||
</row>
|
||
<row>
|
||
<entry><literal>D:</literal></entry>
|
||
<entry>Kernel device node major/minor</entry>
|
||
</row>
|
||
<row>
|
||
<entry><literal>I:</literal></entry>
|
||
<entry>Network interface index</entry>
|
||
</row>
|
||
<row>
|
||
<entry><literal>N:</literal></entry>
|
||
<entry>Kernel device node name</entry>
|
||
</row>
|
||
<row>
|
||
<entry><literal>L:</literal></entry>
|
||
<entry>Device node symlink priority</entry>
|
||
</row>
|
||
<row>
|
||
<entry><literal>S:</literal></entry>
|
||
<entry>Device node symlink</entry>
|
||
</row>
|
||
<row>
|
||
<entry><literal>Q:</literal></entry>
|
||
<entry>Block device sequence number (DISKSEQ)</entry>
|
||
</row>
|
||
<row>
|
||
<entry><literal>V:</literal></entry>
|
||
<entry>Attached driver</entry>
|
||
</row>
|
||
<row>
|
||
<entry><literal>E:</literal></entry>
|
||
<entry>Device property</entry>
|
||
</row>
|
||
</tbody>
|
||
</tgroup>
|
||
</table>
|
||
</refsect2>
|
||
|
||
<refsect2><title>udevadm trigger
|
||
<arg choice="opt"><replaceable>options</replaceable></arg>
|
||
<arg choice="opt"><replaceable>devpath</replaceable>|<replaceable>file</replaceable>|<replaceable>unit</replaceable></arg>
|
||
</title>
|
||
<para>Request device events from the kernel. Primarily used to replay events at system coldplug time.</para>
|
||
|
||
<para>Takes device specifications as positional arguments. See the description of <command>info</command>
|
||
above.</para>
|
||
|
||
<variablelist>
|
||
<varlistentry>
|
||
<term><option>-v</option></term>
|
||
<term><option>--verbose</option></term>
|
||
<listitem>
|
||
<para>Print the list of devices which will be triggered.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-n</option></term>
|
||
<term><option>--dry-run</option></term>
|
||
<listitem>
|
||
<para>Do not actually trigger the event.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-q</option></term>
|
||
<term><option>--quiet</option></term>
|
||
<listitem>
|
||
<para>Suppress error logging in triggering events.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-t</option></term>
|
||
<term><option>--type=<replaceable>TYPE</replaceable></option></term>
|
||
<listitem>
|
||
<para>Trigger a specific type of devices. Valid types are <literal>all</literal>,
|
||
<literal>devices</literal>, and <literal>subsystems</literal>. The default value is
|
||
<literal>devices</literal>.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-c</option></term>
|
||
<term><option>--action=<replaceable>ACTION</replaceable></option></term>
|
||
<listitem>
|
||
<para>Type of event to be triggered. Possible actions are <literal>add</literal>,
|
||
<literal>remove</literal>, <literal>change</literal>, <literal>move</literal>,
|
||
<literal>online</literal>, <literal>offline</literal>, <literal>bind</literal>,
|
||
and <literal>unbind</literal>. Also, the special value <literal>help</literal> can be used
|
||
to list the possible actions. The default value is <literal>change</literal>.
|
||
</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>--prioritized-subsystem=<replaceable>SUBSYSTEM<optional>,<replaceable>SUBSYSTEM</replaceable>…</optional></replaceable></option></term>
|
||
<listitem>
|
||
<para>Takes a comma separated list of subsystems. When triggering events for devices, the
|
||
devices from the specified subsystems and their parents are triggered first. For example,
|
||
if <option>--prioritized-subsystem=block,net</option>, then firstly all block devices and
|
||
their parents are triggered, in the next all network devices and their parents are
|
||
triggered, and lastly the other devices are triggered. This option can be specified
|
||
multiple times, and in that case the lists of the subsystems will be merged. That is,
|
||
<option>--prioritized-subsystem=block --prioritized-subsystem=net</option> is equivalent to
|
||
<option>--prioritized-subsystem=block,net</option>.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-s</option></term>
|
||
<term><option>--subsystem-match=<replaceable>SUBSYSTEM</replaceable></option></term>
|
||
<listitem>
|
||
<para>Trigger events for devices which belong to a
|
||
matching subsystem. This option supports shell style pattern matching.
|
||
When this option is specified more than once, then each matching result is ORed, that is,
|
||
all the devices in each subsystem are triggered.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-S</option></term>
|
||
<term><option>--subsystem-nomatch=<replaceable>SUBSYSTEM</replaceable></option></term>
|
||
<listitem>
|
||
<para>Do not trigger events for devices which belong to a matching subsystem. This option
|
||
supports shell style pattern matching. When this option is specified more than once,
|
||
then each matching result is ANDed, that is, devices which do not match all specified
|
||
subsystems are triggered.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-a</option></term>
|
||
<term><option>--attr-match=<replaceable>ATTRIBUTE</replaceable>=<replaceable>VALUE</replaceable></option></term>
|
||
<listitem>
|
||
<para>Trigger events for devices with a matching sysfs attribute. If a value is specified along
|
||
with the attribute name, the content of the attribute is matched against the given value using
|
||
shell style pattern matching. If no value is specified, the existence of the sysfs attribute is
|
||
checked. When this option is specified multiple times, then each matching result is ANDed,
|
||
that is, only devices which have all specified attributes are triggered.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-A</option></term>
|
||
<term><option>--attr-nomatch=<replaceable>ATTRIBUTE</replaceable>=<replaceable>VALUE</replaceable></option></term>
|
||
<listitem>
|
||
<para>Do not trigger events for devices with a matching sysfs attribute. If a value is specified
|
||
along with the attribute name, the content of the attribute is matched against the given value
|
||
using shell style pattern matching. If no value is specified, the existence of the sysfs attribute
|
||
is checked. When this option is specified multiple times, then each matching result is ANDed,
|
||
that is, only devices which have none of the specified attributes are triggered.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-p</option></term>
|
||
<term><option>--property-match=<replaceable>PROPERTY</replaceable>=<replaceable>VALUE</replaceable></option></term>
|
||
<listitem>
|
||
<para>Trigger events for devices with a matching property value. This option supports shell style
|
||
pattern matching. When this option is specified more than once, then each matching result is ORed,
|
||
that is, devices which have one of the specified properties are triggered.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-g</option></term>
|
||
<term><option>--tag-match=<replaceable>TAG</replaceable></option></term>
|
||
<listitem>
|
||
<para>Trigger events for devices with a matching tag. When this option is specified multiple times,
|
||
then each matching result is ANDed, that is, devices which have all specified tags are triggered.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-y</option></term>
|
||
<term><option>--sysname-match=<replaceable>NAME</replaceable></option></term>
|
||
<listitem>
|
||
<para>Trigger events for devices for which the last component (i.e. the filename) of the
|
||
<filename>/sys/</filename> path matches the specified <replaceable>PATH</replaceable>. This option
|
||
supports shell style pattern matching. When this option is specified more than once, then each
|
||
matching result is ORed, that is, all devices which have any of the specified
|
||
<replaceable>NAME</replaceable> are triggered.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>--name-match=<replaceable>NAME</replaceable></option></term>
|
||
<listitem>
|
||
<para>Trigger events for devices with a matching device path. When this option is specified more than once,
|
||
then each matching result is ORed, that is, all specified devices are triggered.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-b</option></term>
|
||
<term><option>--parent-match=<replaceable>SYSPATH</replaceable></option></term>
|
||
<listitem>
|
||
<para>Trigger events for all children of a given device. When this option is specified more than once,
|
||
then each matching result is ORed, that is, all children of each specified device are triggered.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>--initialized-match</option></term>
|
||
<term><option>--initialized-nomatch</option></term>
|
||
<listitem>
|
||
<para>When <option>--initialized-match</option> is specified, trigger events for devices
|
||
that are already initialized by <command>systemd-udevd</command>, and skip devices that
|
||
are not initialized yet.</para>
|
||
<para>When <option>--initialized-nomatch</option> is specified, trigger events for devices
|
||
that are not initialized by <command>systemd-udevd</command> yet, and skip devices that
|
||
are already initialized.</para>
|
||
<para>Typically, it is essential that applications which intend to use such a match, make
|
||
sure a suitable udev rule is installed that sets at least one property on devices that
|
||
shall be matched. See also Initialized Devices section below for more details.</para>
|
||
<para>WARNING: <option>--initialized-nomatch</option> can potentially save a significant
|
||
amount of time compared to re-triggering all devices in the system and e.g. can be used to
|
||
optimize boot time. However, this is not safe to be used in a boot sequence in general.
|
||
Especially, when udev rules for a device depend on its parent devices (e.g.
|
||
<literal>ATTRS</literal> or <literal>IMPORT{parent}</literal> keys, see
|
||
<citerefentry><refentrytitle>udev</refentrytitle><manvolnum>7</manvolnum></citerefentry>
|
||
for more details), the final state of the device becomes easily unstable with this option.
|
||
</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-w</option></term>
|
||
<term><option>--settle</option></term>
|
||
<listitem>
|
||
<para>Apart from triggering events, also waits for those events to
|
||
finish. Note that this is different from calling <command>udevadm
|
||
settle</command>. <command>udevadm settle</command> waits for all
|
||
events to finish. This option only waits for events triggered by
|
||
the same command to finish.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>--uuid</option></term>
|
||
<listitem>
|
||
<para>Trigger the synthetic device events, and associate a randomized UUID with each. These UUIDs
|
||
are printed to standard output, one line for each event. These UUIDs are included in the uevent
|
||
environment block (in the <literal>SYNTH_UUID=</literal> property) and may be used to track
|
||
delivery of the generated events.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>--wait-daemon[=<replaceable>SECONDS</replaceable>]</option></term>
|
||
<listitem>
|
||
<para>Before triggering uevents, wait for systemd-udevd daemon to be initialized.
|
||
Optionally takes timeout value. Default timeout is 5 seconds. This is equivalent to invoking
|
||
<command>udevadm control --ping</command> before <command>udevadm trigger</command>.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<xi:include href="standard-options.xml" xpointer="help" />
|
||
</variablelist>
|
||
|
||
<para>In addition, optional positional arguments can be used
|
||
to specify device names or sys paths. They must start with
|
||
<filename>/dev/</filename> or <filename>/sys/</filename>
|
||
respectively.</para>
|
||
</refsect2>
|
||
|
||
<refsect2><title>udevadm settle
|
||
<arg choice="opt"><replaceable>options</replaceable></arg>
|
||
</title>
|
||
<para>Watches the udev event queue, and exits if all current events are handled.</para>
|
||
<variablelist>
|
||
<varlistentry>
|
||
<term><option>-t</option></term>
|
||
<term><option>--timeout=<replaceable>SECONDS</replaceable></option></term>
|
||
<listitem>
|
||
<para>Maximum number of seconds to wait for the event
|
||
queue to become empty. The default value is 120 seconds. A
|
||
value of 0 will check if the queue is empty and always
|
||
return immediately. A non-zero value will return an exit
|
||
code of 0 if queue became empty before timeout was reached,
|
||
non-zero otherwise.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-E</option></term>
|
||
<term><option>--exit-if-exists=<replaceable>FILE</replaceable></option></term>
|
||
<listitem>
|
||
<para>Stop waiting if file exists.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<xi:include href="standard-options.xml" xpointer="help" />
|
||
</variablelist>
|
||
|
||
<para>See
|
||
<citerefentry><refentrytitle>systemd-udev-settle.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
|
||
for more information.</para>
|
||
</refsect2>
|
||
|
||
<refsect2><title>udevadm control <replaceable>option</replaceable></title>
|
||
<para>Modify the internal state of the running udev daemon.</para>
|
||
<variablelist>
|
||
<varlistentry>
|
||
<term><option>-e</option></term>
|
||
<term><option>--exit</option></term>
|
||
<listitem>
|
||
<para>Signal and wait for systemd-udevd to exit. No option except for
|
||
<option>--timeout</option> can be specified after this option.
|
||
Note that <filename>systemd-udevd.service</filename> contains
|
||
<option>Restart=always</option> and so as a result, this option restarts systemd-udevd.
|
||
If you want to stop <filename>systemd-udevd.service</filename>, please use the following:
|
||
<programlisting>systemctl stop systemd-udevd-control.socket systemd-udevd-kernel.socket systemd-udevd.service</programlisting>
|
||
</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-l</option></term>
|
||
<term><option>--log-level=<replaceable>value</replaceable></option></term>
|
||
<listitem>
|
||
<para>Set the internal log level of
|
||
<filename>systemd-udevd</filename>. Valid values are the
|
||
numerical syslog priorities or their textual
|
||
representations: <option>emerg</option>,
|
||
<option>alert</option>, <option>crit</option>,
|
||
<option>err</option>, <option>warning</option>,
|
||
<option>notice</option>, <option>info</option>, and
|
||
<option>debug</option>.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-s</option></term>
|
||
<term><option>--stop-exec-queue</option></term>
|
||
<listitem>
|
||
<para>Signal systemd-udevd to stop executing new events. Incoming events
|
||
will be queued.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-S</option></term>
|
||
<term><option>--start-exec-queue</option></term>
|
||
<listitem>
|
||
<para>Signal systemd-udevd to enable the execution of events.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-R</option></term>
|
||
<term><option>--reload</option></term>
|
||
<listitem>
|
||
<para>Signal systemd-udevd to reload the rules files and other databases like the kernel
|
||
module index. Reloading rules and databases does not apply any changes to already
|
||
existing devices; the new configuration will only be applied to new events.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-p</option></term>
|
||
<term><option>--property=<replaceable>KEY</replaceable>=<replaceable>value</replaceable></option></term>
|
||
<listitem>
|
||
<para>Set a global property for all events.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-m</option></term>
|
||
<term><option>--children-max=</option><replaceable>value</replaceable></term>
|
||
<listitem>
|
||
<para>Set the maximum number of events, systemd-udevd will handle at the
|
||
same time.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>--ping</option></term>
|
||
<listitem>
|
||
<para>Send a ping message to systemd-udevd and wait for the reply. This may be useful to check that
|
||
systemd-udevd daemon is running.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-t</option></term>
|
||
<term><option>--timeout=</option><replaceable>seconds</replaceable></term>
|
||
<listitem>
|
||
<para>The maximum number of seconds to wait for a reply from systemd-udevd.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<xi:include href="standard-options.xml" xpointer="help" />
|
||
</variablelist>
|
||
</refsect2>
|
||
|
||
<refsect2><title>udevadm monitor
|
||
<arg choice="opt"><replaceable>options</replaceable></arg>
|
||
</title>
|
||
<para>Listens to the kernel uevents and events sent out by a udev rule
|
||
and prints the devpath of the event to the console. It can be used to analyze the
|
||
event timing, by comparing the timestamps of the kernel uevent and the udev event.
|
||
</para>
|
||
<variablelist>
|
||
<varlistentry>
|
||
<term><option>-k</option></term>
|
||
<term><option>--kernel</option></term>
|
||
<listitem>
|
||
<para>Print the kernel uevents.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-u</option></term>
|
||
<term><option>--udev</option></term>
|
||
<listitem>
|
||
<para>Print the udev event after the rule processing.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-p</option></term>
|
||
<term><option>--property</option></term>
|
||
<listitem>
|
||
<para>Also print the properties of the event.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-s</option></term>
|
||
<term><option>--subsystem-match=<replaceable>string[/string]</replaceable></option></term>
|
||
<listitem>
|
||
<para>Filter kernel uevents and udev events by subsystem[/devtype]. Only events with a matching subsystem value will pass.
|
||
When this option is specified more than once, then each matching result is ORed, that is, all devices in the specified
|
||
subsystems are monitored.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-t</option></term>
|
||
<term><option>--tag-match=<replaceable>string</replaceable></option></term>
|
||
<listitem>
|
||
<para>Filter udev events by tag. Only udev events with a given tag attached will pass.
|
||
When this option is specified more than once, then each matching result is ORed, that is, devices which have one of the
|
||
specified tags are monitored.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<xi:include href="standard-options.xml" xpointer="help" />
|
||
</variablelist>
|
||
</refsect2>
|
||
|
||
<refsect2><title>udevadm test
|
||
<arg choice="opt"><replaceable>options</replaceable></arg>
|
||
<arg choice="opt"><replaceable>devpath</replaceable>|<replaceable>file</replaceable>|<replaceable>unit</replaceable></arg>
|
||
</title>
|
||
<para>Simulate a udev event run for the given device, and print debug output.</para>
|
||
<variablelist>
|
||
<varlistentry>
|
||
<term><option>-a</option></term>
|
||
<term><option>--action=<replaceable>ACTION</replaceable></option></term>
|
||
<listitem>
|
||
<para>Type of event to be simulated. Possible actions are <literal>add</literal>,
|
||
<literal>remove</literal>, <literal>change</literal>, <literal>move</literal>,
|
||
<literal>online</literal>, <literal>offline</literal>, <literal>bind</literal>,
|
||
and <literal>unbind</literal>. Also, the special value <literal>help</literal> can be used
|
||
to list the possible actions. The default value is <literal>add</literal>.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
<varlistentry>
|
||
<term><option>-N</option></term>
|
||
<term><option>--resolve-names=<constant>early</constant>|<constant>late</constant>|<constant>never</constant></option></term>
|
||
<listitem>
|
||
<para>Specify when udevadm should resolve names of users
|
||
and groups. When set to <constant>early</constant> (the
|
||
default), names will be resolved when the rules are
|
||
parsed. When set to <constant>late</constant>, names will
|
||
be resolved for every event. When set to
|
||
<constant>never</constant>, names will never be resolved
|
||
and all devices will be owned by root.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<xi:include href="standard-options.xml" xpointer="help" />
|
||
</variablelist>
|
||
</refsect2>
|
||
|
||
<refsect2><title>udevadm test-builtin
|
||
<arg choice="opt"><replaceable>options</replaceable></arg>
|
||
<arg><replaceable>command</replaceable></arg>
|
||
<arg choice="opt"><replaceable>devpath</replaceable>|<replaceable>file</replaceable>|<replaceable>unit</replaceable></arg>
|
||
</title>
|
||
<para>Run a built-in command <replaceable>COMMAND</replaceable>
|
||
for device <replaceable>DEVPATH</replaceable>, and print debug
|
||
output.</para>
|
||
<variablelist>
|
||
<varlistentry>
|
||
<term><option>-a</option></term>
|
||
<term><option>--action=<replaceable>ACTION</replaceable></option></term>
|
||
<listitem>
|
||
<para>Type of event to be simulated. Possible actions are <literal>add</literal>,
|
||
<literal>remove</literal>, <literal>change</literal>, <literal>move</literal>,
|
||
<literal>online</literal>, <literal>offline</literal>, <literal>bind</literal>,
|
||
and <literal>unbind</literal>. Also, the special value <literal>help</literal> can be used
|
||
to list the possible actions. The default value is <literal>add</literal>.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<xi:include href="standard-options.xml" xpointer="help" />
|
||
</variablelist>
|
||
</refsect2>
|
||
|
||
<refsect2>
|
||
<title>udevadm verify
|
||
<arg choice="opt"><replaceable>options</replaceable></arg>
|
||
<arg choice="plain" rep="repeat"><replaceable>file</replaceable></arg>
|
||
…
|
||
</title>
|
||
|
||
<para>Verify syntactic and semantic correctness of udev rules files.</para>
|
||
|
||
<para>Positional arguments should be used to specify one or more files to check.</para>
|
||
|
||
<para>The exit status is <constant>0</constant> if all specified udev rules files
|
||
are syntactically and semantically correct, and a non-zero error code otherwise.</para>
|
||
|
||
<variablelist>
|
||
<varlistentry>
|
||
<term><option>-N</option></term>
|
||
<term><option>--resolve-names=<constant>early</constant>|<constant>never</constant></option></term>
|
||
<listitem>
|
||
<para>Specify when udevadm should resolve names of users
|
||
and groups. When set to <constant>early</constant> (the
|
||
default), names will be resolved when the rules are
|
||
parsed. When set to <constant>never</constant>, names will
|
||
never be resolved.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<xi:include href="standard-options.xml" xpointer="help" />
|
||
</variablelist>
|
||
</refsect2>
|
||
|
||
<refsect2>
|
||
<title>udevadm wait
|
||
<arg choice="opt"><replaceable>options</replaceable></arg>
|
||
<arg choice="opt"><replaceable>device|syspath</replaceable></arg>
|
||
…
|
||
</title>
|
||
|
||
<para>Wait for devices or device symlinks being created and initialized by
|
||
<command>systemd-udevd</command>. Each device path must start with
|
||
<literal>/dev/</literal> or <literal>/sys/</literal>, e.g. <literal>/dev/sda</literal>,
|
||
<literal>/dev/disk/by-path/pci-0000:3c:00.0-nvme-1-part1</literal>,
|
||
<literal>/sys/devices/pci0000:00/0000:00:1f.6/net/eth0</literal>, or
|
||
<literal>/sys/class/net/eth0</literal>. This can take multiple devices. This may be useful for
|
||
waiting for devices being processed by <command>systemd-udevd</command> after e.g. partitioning
|
||
or formatting the devices.</para>
|
||
|
||
<variablelist>
|
||
<varlistentry>
|
||
<term><option>-t</option></term>
|
||
<term><option>--timeout=<replaceable>SECONDS</replaceable></option></term>
|
||
<listitem>
|
||
<para>Maximum number of seconds to wait for the specified devices or device symlinks being
|
||
created, initialized, or removed. The default value is <literal>infinity</literal>.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--initialized=<replaceable>BOOL</replaceable></option></term>
|
||
<listitem>
|
||
<para>Check if <command>systemd-udevd</command> initialized devices. Defaults to true. When
|
||
false, the command only checks if the specified devices exist. Set false to this setting if
|
||
there is no udev rules for the specified devices, as the devices will never be considered
|
||
as initialized in that case. See Initialized Devices section below for more details.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--removed</option></term>
|
||
<listitem>
|
||
<para>When specified, the command wait for devices being removed instead of created or
|
||
initialized. If this is specified, <option>--initialized=</option> will be ignored.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--settle</option></term>
|
||
<listitem>
|
||
<para>When specified, also watches the udev event queue, and wait for all queued events
|
||
being processed by <command>systemd-udevd</command>.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<xi:include href="standard-options.xml" xpointer="help" />
|
||
</variablelist>
|
||
</refsect2>
|
||
|
||
<refsect2>
|
||
<title>udevadm lock
|
||
<arg choice="opt"><replaceable>options</replaceable></arg>
|
||
<arg choice="opt"><replaceable>command</replaceable></arg>
|
||
…
|
||
</title>
|
||
|
||
<para><command>udevadm lock</command> takes an (advisory) exclusive lock on a block device (or all
|
||
specified devices), as per <ulink url="https://systemd.io/BLOCK_DEVICE_LOCKING">Locking Block Device
|
||
Access</ulink> and invokes a program with the locks taken. When the invoked program exits the locks
|
||
are automatically released and its return value is propagated as exit code of <command>udevadm
|
||
lock</command>.</para>
|
||
|
||
<para>This tool is in particular useful to ensure that
|
||
<citerefentry><refentrytitle>systemd-udevd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
|
||
does not probe a block device while changes are made to it, for example partitions created or file
|
||
systems formatted. Note that many tools that interface with block devices natively support taking
|
||
relevant locks, see for example
|
||
<citerefentry project='man-pages'><refentrytitle>sfdisk</refentrytitle><manvolnum>8</manvolnum></citerefentry>'s
|
||
<option>--lock</option> switch.</para>
|
||
|
||
<para>The command expects at least one block device specified via <option>--device=</option> or
|
||
<option>--backing=</option>, and a command line to execute as arguments.</para>
|
||
|
||
<variablelist>
|
||
<varlistentry>
|
||
<term><option>--device=<replaceable>DEVICE</replaceable></option></term>
|
||
<term><option>-d <replaceable>DEVICE</replaceable></option></term>
|
||
|
||
<listitem><para>Takes a path to a device node of the device to lock. This switch may be used
|
||
multiple times (and in combination with <option>--backing=</option>) in order to lock multiple
|
||
devices. If a partition block device node is specified the containing "whole" block device is
|
||
automatically determined and used for the lock, as per the specification. If multiple devices are
|
||
specified, they are deduplicated, sorted by the major/minor of their device nodes and then locked
|
||
in order.</para>
|
||
|
||
<para>This switch must be used at least once, to specify at least one device to
|
||
lock. (Alternatively, use <option>--backing=</option>, see below.)</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--backing=<replaceable>PATH</replaceable></option></term>
|
||
<term><option>-b <replaceable>PATH</replaceable></option></term>
|
||
|
||
<listitem><para>If a path to a device node is specified, identical to
|
||
<option>--device=</option>. However, this switch alternatively accepts a path to a regular file or
|
||
directory, in which case the block device of the file system the file/directory resides on is
|
||
automatically determined and used as if it was specified with
|
||
<option>--device=</option>.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--timeout=<replaceable>SECS</replaceable></option></term>
|
||
<term><option>-t <replaceable>SECS</replaceable></option></term>
|
||
|
||
<listitem><para>Specifies how long to wait at most until all locks can be taken. Takes a value in
|
||
seconds, or in the usual supported time units, see
|
||
<citerefentry><refentrytitle>systemd.time</refentrytitle><manvolnum>7</manvolnum></citerefentry>. If
|
||
specified as zero the lock is attempted and if not successful the invocation will immediately
|
||
fail. If passed as <literal>infinity</literal> (the default) the invocation will wait indefinitely
|
||
until the lock can be acquired. If the lock cannot be taken in the specified time the specified
|
||
command will not be executed and the invocation will fail.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--print</option></term>
|
||
<term><option>-p</option></term>
|
||
|
||
<listitem><para>Instead of locking the specified devices and executing a command, just print the
|
||
device paths that would be locked, and execute no command. This command is useful to determine
|
||
the "whole" block device in case a partition block device is specified. The devices will be sorted
|
||
by their device node major number as primary ordering key and the minor number as secondary
|
||
ordering key (i.e. they are shown in the order they'd be locked). Note that the number of lines
|
||
printed here can be less than the number of <option>--device=</option> and
|
||
<option>--backing=</option> switches specified in case these resolve to the same "whole"
|
||
devices.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<xi:include href="standard-options.xml" xpointer="help" />
|
||
</variablelist>
|
||
</refsect2>
|
||
</refsect1>
|
||
|
||
<refsect1>
|
||
<title>Initialized Devices</title>
|
||
|
||
<para>Initialized devices are those for which at least one udev rule already completed execution
|
||
– for any action but <literal>remove</literal> — that set a property or other device setting (and
|
||
thus has an entry in the udev device database). Devices are no longer considered initialized if a
|
||
<literal>remove</literal> action is seen for them (which removes their entry in the udev device
|
||
database). Note that devices that have no udev rules are never considered initialized, but might
|
||
still be announced via the sd-device API (or similar).</para>
|
||
</refsect1>
|
||
|
||
<refsect1>
|
||
<title>Example</title>
|
||
|
||
<example>
|
||
<title>Format a File System</title>
|
||
|
||
<para>Take a lock on the backing block device while creating a file system, to ensure that
|
||
<command>systemd-udevd</command> doesn't probe or announce the new superblock before it is
|
||
comprehensively written:</para>
|
||
|
||
<programlisting># udevadm lock --device=/dev/sda1 mkfs.ext4 /dev/sda1</programlisting>
|
||
</example>
|
||
|
||
<example>
|
||
<title>Format a RAID File System</title>
|
||
|
||
<para>Similar, but take locks on multiple devices at once:</para>
|
||
|
||
<programlisting># udevadm lock --device=/dev/sda1 --device=/dev/sdb1 mkfs.btrfs /dev/sda1 /dev/sdb1</programlisting>
|
||
</example>
|
||
|
||
<example>
|
||
<title>Copy in a File System</title>
|
||
|
||
<para>Take a lock on the backing block device while copying in a prepared file system image, to ensure
|
||
that <command>systemd-udevd</command> doesn't probe or announce the new superblock before it is fully
|
||
written:</para>
|
||
|
||
<programlisting># udevadm lock -d /dev/sda1 dd if=fs.raw of=/dev/sda1</programlisting>
|
||
</example>
|
||
</refsect1>
|
||
|
||
<refsect1>
|
||
<title>See Also</title>
|
||
<para><citerefentry>
|
||
<refentrytitle>udev</refentrytitle><manvolnum>7</manvolnum>
|
||
</citerefentry>,
|
||
<citerefentry>
|
||
<refentrytitle>systemd-udevd.service</refentrytitle><manvolnum>8</manvolnum>
|
||
</citerefentry></para>
|
||
</refsect1>
|
||
</refentry>
|