9 New and updated keymaps.
15 The udev database has changed, After installation of a new udev
16 version, 'udevadm info --convert-db' should be called, to let the new
17 udev/libudev version read the already stored data.
19 udevadm now supports quoting of property values, and prefixing of
21 $ udevadm info --export --export-prefix=MY_ --query=property -n sda
29 udev_device_get_is_initialized()
30 udev_enumerate_add_match_is_initialized()
31 to be able to skip devices the kernel has created , but udev has
35 udev_device_get_usec_since_initialized()
36 to retrieve the "age" of a udev device record.
38 GUdev supports a more generic GUdevEnumerator class, udev TAG
39 handling, device initialization and timestamp now.
41 The counterpart of /sys/dev/{char,block}/$major:$minor,
42 /dev/{char,block}/$major:$minor symlinks are now unconditionally
43 created, even when no rule files exist.
45 New and updated keymaps.
51 GUdev moved from /usr to /.
61 Persistent network naming rules are disabled inside of Qemu/KVM now.
63 New and updated keymaps.
65 Udev gets unconditionally enabled on systemd installations now. There
66 is no longer the need to to run 'systemctl enable udev.service'.
80 New and fixed keymaps.
82 Install systemd service files if applicable.
88 All distribution specific rules are removed from the udev source tree,
89 most of them are no longer needed. The Gentoo rules which allow to support
90 older kernel versions, which are not covered by the default rules anymore
91 has moved to rules/misc/30-kernel-compat.rules.
97 The option --debug-trace and the environemnt variable UDEVD_MAX_CHILDS=
98 was removed from udevd.
100 Udevd now checks the kernel commandline for the following variables:
101 udev.log-priority=<syslog priority>
102 udev.children-max=<maximum number of workers>
103 udev.exec-delay=<seconds to delay the execution of RUN=>
104 to help debuging coldplug setups where the loading of a kernel
105 module crashes the system.
107 The subdirectory in the source tree rules/packages has been renamed to
108 rules/arch, anc contains only architecture specific rules now.
118 Now the udev daemon itself, does on startup:
119 - copy the content of /lib/udev/devices to /dev
120 - create the standard symlinks like /dev/std{in,out,err},
121 /dev/core, /dev/fd, ...
122 - use static node information provided by kernel modules
123 and creates these nodes to allow module on-demand loading
124 - possibly apply permissions to all ststic nodes from udev
125 rules which are annotated to match a static node
127 The default mode for a device node is 0600 now to match the kernel
128 created devtmpfs defaults. If GROUP= is specified and no MODE= is
129 given the default will be 0660.
135 Udev now gradually starts to pass control over the primary device nodes
136 and their names to the kernel, and will in the end only manage the
137 permissions of the node, and possibly create additional symlinks.
138 As a first step NAME="" will be ignored, and NAME= setings with names
139 other than the kernel provided name will result in a logged warning.
140 Kernels that don't provide device names, or devtmpfs is not used, will
141 still work as they did before, but it is strongly recommended to use
142 only the same names for the primary device node as the recent kernel
143 provides for all devices.
147 Fix broken firmware loader search path.
153 "udevadm trigger" defaults to "change" events now instead of "add"
154 events. The "udev boot script" might need to add "--action=add" to
155 the trigger command if not already there, in case the initial coldplug
156 events are expected as "add" events.
158 The option "all_partitons" was removed from udev. This should not be
159 needed for usual hardware. Udev can not safely make assumptions
160 about non-existing partition major/minor numbers, and therefore no
161 longer provide this unreliable and unsafe option.
163 The option "ignore_remove" was removed from udev. With devtmpfs
164 udev passed control over device nodes to the kernel. This option
165 should not be needed, or can not work as advertised. Neither
166 udev nor the kernel will remove device nodes which are copied from
167 the /lib/udev/devices/ directory.
169 All "add|change" matches are replaced by "!remove" in the rules and
170 in the udev logic. All types of events will update possible symlinks
171 and permissions, only "remove" is handled special now.
173 The modem modeswitch extra was removed and the external usb_modeswitch
174 program should be used instead.
176 New and fixed keymaps.
186 Kernels with SYSFS_DEPRECATED=y are not supported since a while. Many users
187 depend on the current sysfs layout and the information not available in the
188 deprecated layout. All remaining support for the deprecated sysfs layout is
193 Fix for a possible endless loop in the new input_id program.
199 The option "ignore_device" does no longer exist. There is no way to
200 ignore an event, as libudev events can not be suppressed by rules.
201 It only prevented RUN keys from being executed, which results in an
202 inconsistent behavior in current setups.
204 BUS=, SYSFS{}=, ID= are long deprecated and should be SUBSYSTEM(S)=,
205 ATTR(S){}=, KERNEL(S)=. It will cause a warning once for every rule
208 The support for the deprecated IDE devices has been removed from the
209 default set of rules. Distros who still care about non-libata drivers
210 need to add the rules to the compat rules file.
212 The ID_CLASS property on input devices has been replaced by the more accurate
213 set of flags ID_INPUT_{KEYBOARD,KEY,MOUSE,TOUCHPAD,TABLET,JOYSTICK}. These are
214 determined by the new "input_id" prober now. Some devices, such as touchpads,
215 can have several classes. So if you previously had custom udev rules which e. g.
216 checked for ENV{ID_CLASS}=="kbd", you need to replace this with
217 ENV{ID_INPUT_KEYBOARD}=="?*".
223 To support DEVPATH strings larger than the maximum file name length, the
224 private udev database format has changed. If some software still reads the
225 private files in /dev/.udev/, which it shouldn't, now it's time to fix it.
226 Please do not port anything to the new format again, everything in /dev/.udev
227 is and always was private to udev, and may and will change any time without
230 Multiple devices claiming the same names in /dev are limited to symlinks
231 only now. Mixing identical symlink names and node names is not supported.
232 This reduces the amount of data in the database significantly.
234 NAME="%k" causes a warning now. It's is and always was completely superfluous.
235 It will break kernel supplied DEVNAMEs and therefore it needs to be removed
238 Most NAME= instructions got removed. Kernel 2.6.31 supplies the needed names
239 if they are not the default. To support older kernels, the NAME= rules need to
240 be added to the compat rules file.
242 Symlinks to udevadm with the old command names are no longer resolved to
243 the udevadm commands.
245 The udev-acl tool got adopted to changes in ConsoleKit. Version 0.4.1 is
248 The option "last_rule" does no longer exist. Its use breaks too many
249 things which expect to be run from independent later rules, and is an idication
250 that something needs to be fixed properly instead.
252 The gudev API is no longer marked as experimental,
253 G_UDEV_API_IS_SUBJECT_TO_CHANGE is no longer needed. The gudev introspection
254 is enabled by default now. Various projects already depend on introspection
255 information to bind dynamic languages to the gudev interfaces.
261 The udevadm trigger "--retry-failed" option, which is replaced since quite
262 a while by "--type=failed" is removed.
264 The failed tracking was not working at all for a few releases. The RUN
265 option "ignore_error" is replaced by a "fail_event_on_error" option, and the
266 default is not to track any failing RUN executions.
268 New keymaps, new modem, hid2hci updated.
272 Fix possible crash in udevd when worker processes are busy, rules are
273 changed at the same time, and workers get killed to reload the rules.
279 Properties set with ENV{.FOO}="bar" are marked private by starting the
280 name with a '.'. They will not be stored in the database, and not be
281 exported with the event.
283 Firmware files are looked up in:
284 /lib/firmware/updates/$(uname -r)
285 /lib/firmware/updates
286 /lib/firmware/$(uname -r)
290 ATA devices switched the property from ID_BUS=scsi to ID_BUS=ata.
291 ata_id, instead of scsi_id, is the default tool now for ATA devices.
297 The configure options have changed because another library needs to be
298 installed in a different location. Instead of exec_prefix and udev_prefix,
299 libdir, rootlibdir and libexecdir are used. The Details are explained in
302 Event processes now get re-used after they handled an event. This reduces
303 the number of forks and the pressure on the CPU significantly, because
304 cloned event processes no longer cause page faults in the main daemon.
305 After the events have settled, a few worker processes stay around for
306 future events, all others get cleaned up.
308 To be able to use signalfd(), udev depends on kernel version 2.6.25 now.
309 Also inotify support is mandatory now to run udev.
311 The format of the queue exported by the udev damon has changed. There is
312 no longer a /dev/.udev/queue/ directory. The current event queue can be
313 accessed with udevadm settle and libudedv.
315 Libudev does not have the unstable API header anymore. From now on,
316 incompatible changes will be handled by bumping the library major version.
318 To build udev from the git tree gtk-doc is needed now. The tarballs will
319 build without it and contain the pre-built documentation. An online copy
321 http://www.kernel.org/pub/linux/utils/kernel/hotplug/libudev/
323 The tools from the udev-extras repository have been merged into the main
324 udev repository. Some of the extras have larger external dependencies, and
325 they can be disabled with the configure switch --disable-extras.
331 The program vol_id and the library libvolume_id are removed from the
332 repository. Libvolume_id is merged with libblkid from the util-linux-ng
333 package. Persistent disk links for label and uuid depend on the
334 util-linux-ng version (2.15) of blkid now. Older versions of blkid
335 can not be used with udev.
337 Libudev allows to subscribe to udev events. To prevent unwanted messages
338 to be delivered, and waking up the subscribing process, a filter can be
339 installed, to drop messages inside a kernel socket filter. The filters
340 match on the <subsytem>:<devtype> properties of the device.
341 This is part of the ongoing effort to replace HAL, and switch current
342 users over to directly use libudev.
343 Libudev is still marked as experimental, and its interface might
344 eventually change if needed, but no major changes of the currently exported
345 interface are expected anymore, and a first stable release should happen
348 A too old kernel (2.6.21) or a kernel with CONFIG_SYSFS_DEPRECATED
349 is not supported since while and udevd will log an error message at
350 startup. It should still be able to boot-up, but advanced rules and system
351 services which depend on the information not available in the old sysfs
352 format will fail to work correctly.
354 DVB device naming is supplied by the kernel now. In case older kernels
355 need to be supported, the old shell script should be added to a compat
362 The processed udev events get send back to the netlink socket. Libudev
363 provides access to these events. This is work-in-progress, to replace
364 the DeviceKit daemon functionality directly with libudev. There are
365 upcoming kernel changes to allow non-root users to subcribe to these
372 "udevadm settle" now optionally accepts a range of events to wait for,
373 instead of waiting for "all" events.
379 The installed watch for block device metadata changes is now removed
380 during event hadling, because some (broken) tools may be called from udev
381 rules and (wrongly) open the device with write access. After the finished
382 event handling the watch is restored.
388 Device nodes can be watched for changes with inotify with OPTIONS="watch".
389 If closed after being opened for writing, a "change" uevent will occur.
390 /dev/disk/by-{label,uuid}/* symlinks will be automatically updated.
396 The udevadm test command has no longer a --force option, nodes and symlinks
397 are always updated with a test run now.
399 The udevd daemon can be started with --resolve-names=never to avoid all user
400 and group lookups (e.g. in cut-down systems) or --resolve-names=late to
401 lookup user and groups every time events are handled.
407 We are currently merging the Ubuntu rules in the udev default rules,
408 and get one step closer to provide a common Linux /dev setup, regarding
409 device names, symlinks, and default device permissions. On udev startup,
410 we now expect the following groups to be resolvable to their ids with
412 disk, cdrom, floppy, tape, audio, video, lp, tty, dialout, kmem.
413 LDAP setups need to make sure, that these groups are always resolvable at
414 bootup, with only the rootfs mounted, and without network access available.
416 Some systems may need to add some new, currently not used groups, or need
417 to add some users to new groups, but the cost of this change is minimal,
418 compared to the pain the current, rather random, differences between the
419 various distributions cause for upstream projects and third-party vendors.
421 In general, "normal" users who log into a machine should never be a member
422 of any such group, but the device-access should be managed by dynamic ACLs,
423 which get added and removed for the specific users on login/logout and
424 session activity/inactivity. These groups are only provided for custom setups,
425 and mainly system services, to allow proper privilege separation.
426 A video-streaming daemon uid would be a member of "audio" and "video", to get
427 access to the sound and video devices, but no "normal" user should ever belong
428 to the "audio" group, because he could listen to the built-in microphone with
429 any ssh-session established from the other side of the world.
431 /dev/serial/by-{id,path}/ now contains links for ttyUSB devices,
432 which do not depend on the kernel device name. As usual, unique
433 devices - only a single one per product connected, or a real
434 USB serial number in the device - are always found with the same
435 name in the by-id/ directory.
436 Completely identical devices may overwrite their names in by-id/
437 and can only be found reliably in the by-path/ directory. Devices
438 specified by by-path/ must not change their connection, like the
439 USB port number they are plugged in, to keep their name.
441 To support some advanced features, Linux 2.6.22 is the oldest supported
442 version now. The kernel config with enabled SYSFS_DEPRECATED is no longer
443 supported. Older kernels should still work, and devices nodes should be
444 reliably created, but some rules and libudev will not work correctly because
445 the old kernels do not provide the expected information or interfaces.
451 Fix for a possible segfault while swapping network interface names in udev
458 The group "video" is part of the default rules now.
462 Bugfix for kernels using SYSFS_DEPRECATED* option and finding parent
463 block devices in some cases. No common distro uses this option anymore,
464 and we do not get enough testing for this and recent udev versions. If
465 this option is not needed to run some old distro with a new kernel,
466 it should be disabled in the kernel config.
468 Bugfix for the $links substitution variable, which may crash if no links
469 are created. This should not happen in usual setups because we always
470 create /dev/{block,char}/ links.
472 The strings of the parsed rules, which are kept in memory, no longer
473 contain duplicate entries, or duplicate tails of strings. This, and the
474 new rules parsing/matching code reduces the total in-memory size of
475 a huge distro rule sets to 0.08 MB, compared to the 1.2MB of udev
478 The export of DEVTYPE=disk/partition got removed from the default
479 rules. This value is available from the kernel. The pnp shell script
480 modprobe hack is removed from the default rules. ACPI devices have _proper_
481 modalias support and take care of the same functionality.
482 Installations which support old kernels, but install current default
483 udev rules may want to add that to the compat rules file.
485 Libvolume_id now always probes for all known filesystems, and does not
486 stop at the first match. Some filesystems are marked as "exclusive probe",
487 and if any other filesytem type matches at the same time, libvolume_id
488 will, by default, not return any probing result. This is intended to prevent
489 mis-detection with conflicting left-over signatures found from earlier
490 file system formats. That way, we no longer depend on the probe-order
491 in case of multiple competing signatures. In some setups the kernel allows
492 to mount a volume with just the old filesystem signature still in place.
493 This may damage the new filesystem and cause data-loss, just by mounting
494 it. Because volume_id can not decide which one the correct signature is,
495 the wrong signatures need to be removed manually from the volume, or the
496 volume needs to be reformatted, to enable filesystem detection and possible
501 Fix segfault if compiled without optimization and dbg() does not get
502 compiled out and uses variables which are not available.
506 Bugfixes. (And maybe new bugs. :))
508 The rule matching engine got converted from a rule list to a token
509 array which reduced the in-memory rules representation of a full
510 featured distros with thousends of udev rules from 1.2MB to 0.12 MB.
511 Limits like 5 ENV and ATTR matches, and one single instance for most
512 other keys per rule are gone.
514 The NAME assignment is no longer special cased. If later rules assign
515 a NAME value again, the former value will be overwritten. As usual
516 for most other keys, the NAME value can be protected by doing a final
517 assignment with NAME:="<value>".
519 All udev code now uses libudev, which is also exported. The library
520 is still under development, marked as experimental, and its interface
521 may change as long as the DeviceKit integration is not finished.
523 Many thanks to Alan Jenkins for his continuous help, and finding and
524 optimizing some of the computing expensive parts.
530 Kernel devices and device nodes are connected now by reverse indizes in
531 /sys and /dev. A device number retrieved by a stat() or similar, the
532 kernel device directory can be found by looking up:
533 /sys/dev/{block,char}/<maj>:<min>
534 and the device node of the same device by looking up:
535 /dev/{block,char}/<maj>:<min>
539 Fix recently introduced bug, which caused a compilation without large
540 file support, where vol_id does not recognize raid signatures at the end
543 Firewire disks now create both, by-id/scsi-* and by-id/ieee-* links.
544 Seems some kernel versions prevent the creation of the ieee-* links,
545 so people used the scsi-* link which disappeared now.
547 More libudev work. Almost all udevadm functionality comes from libudev
550 udevadm trigger has a new option --type, which allows to trigger events
551 for "devices", for "subsystems", or "failed" devices. The old option
552 --retry-failed" still works, but is no longer mentioned in the man page.
558 The udevadm info --device-id-of-file= output has changed to use
559 the obvious format. Possible current users should use the --export
560 option which is not affected.
562 The old udev commands symlinks to udevadm are not installed, if
563 these symlinks are used, a warning is printed.
569 Optical drive's media is no longer probed for raid signatures,
570 reading the end of the device causes some devices to malfunction.
571 Also the offset of the last session found is used now to probe
574 The volume_id library got a major version number update to 1,
575 some deprecated functions are removed.
577 A shared library "libudev" gets installed now to provide access
578 to udev device information. DeviceKit, the successor of HAL, will
579 need this library to access the udev database and search sysfs for
581 The library is currently in an experimental state, also the API is
582 expected to change, as long as the DeviceKit integration is not
587 We use ./configure now. See INSTALL for details. Current
590 "/usr" - prefix for man pages, include files
592 "" - the root filesystem, prefix for libs and binaries
596 "lib" - directory name for libraries, not a path name
597 multilib 64bit systems may use "lib64" instead of "lib"
599 compile-in verbose debug messages
601 disable all logging and compile-out all log strings
603 link against SELInux libraries, to set the expected context
606 In the default rules, the group "disk" gets permissions 0660 instead
607 of 0640. One small step closer to unify distro rules. Some day, all
608 distros hopefully end up with the same set of rules.
610 No symlinks to udevadm are installed anymore, if they are still needed,
611 they should be provided by the package.
617 Default udev rules, which are not supposed to be edited by the user, should
618 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
619 the udev package and will be replaced with an update. Udev will pick up rule
621 /lib/udev/rules.d/ - default installed rules
622 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
623 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
624 It does not matter in which directory a rule file lives, all files are sorted
627 To help creating /dev/root, we have now:
628 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
631 In case the current --device-id-of-file is already used, please switch to
632 the --export format version, it saves the output parsing and the old
633 format will be changed to use ':' as a separator, like the format in the
638 Fix cdrom_id to properly recognize blank media.
644 Tape drive id-data is queried from /dev/bsg/* instead of the tape
645 nodes. This avoids rewinding tapes on open().
651 The symlinks udevcontrol and udevtrigger are no longer installed by
654 The scsi_id program does not depend on sysfs anymore. It can speak
655 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
656 data, which should solve some old problems with tape devices, where
657 we better do not open all tape device nodes to identify the device.
663 The cdrom_id program is replaced by an advanced version, which can
664 detect most common device types, and also properties of the inserted
665 media. This is part of moving some basic functionality from HAL into
666 udev (and the kernel).
672 The last WAIT_FOR_SYSFS rule is removed from the default rules.
674 The symlinks to udevadm for the debugging tools: udevmonitor and
675 udevtest are no longer created.
677 The symlinks to the udevadm man page for the old tool names are
680 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
681 should be prefixed with '@' to indicate that the path is not a
692 Udevstart is removed from the tree, it did not get installed for
693 a long time now, and is long replaced by trigger and settle.
699 All udev tools are merged into a single binary called udevadm.
700 The old names of the tools are built-in commands in udevadm now.
701 Symlinks to udevadm, with the names of the old tools, provide
702 the same functionality as the standalone tools. There is also
703 only a single udevadm.8 man page left for all tools.
705 Tools like mkinitramfs should be checked, if they need to include
706 udevadm in the list of files.
716 The etc/udev/rules.d/ directory now contains a default set of basic
717 udev rules. This initial version is the result of a rules file merge
718 of Fedora and openSUSE. For these both distros only a few specific
719 rules are left in their own file, named after the distro. Rules which
720 are optionally installed, because they are only valid for a specific
721 architecture, or rules for subsystems which are not always used are
722 in etc/udev/packages/.
728 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
729 actions by dynamically created rules.
731 SYMLINK=="<value>" matches agains the entries in the list of
732 currently defined symlinks. The links are not created in the
733 filesystem at that point in time, but the values can be matched.
735 RUN{ignore_error}+="<program>" will ignore any exit code from the
736 program and not record as a failed event.
742 Final merge of patches/features from the Ubuntu package.
748 Control characters in filesystem label strings are no longer silenty
749 removed, but hex-encoded, to be able to uniquely identify the device
750 by its symlink in /dev/disk/by-label/.
751 If libvolume_id is used by mount(8), LABEL= will work as expected,
752 if slashes or other characters are used in the label string.
754 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
755 can be specified now. The TEST key accepts an optional mode mask
756 TEST{0100}=="<is executable file>".
758 Scsi_id now supports a mode without expecting scsi-specific sysfs
759 entries to allow the extraction of cciss-device persistent properties.
765 In the future, we may see uuid's which are just simple character
766 strings (see the DDF Raid Specification). For that reason vol_id now
767 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
768 the creation of symlinks, the *_SAFE values ensure, that no control
769 or whitespace characters are used in the filename.
771 Possible users of libvolume_id, please use the volume_id_get_* functions.
772 The public struct will go away in a future release of the library.
778 Removal of useless extras/eventrecorder.sh.
788 The directory multiplexer for dev.d/ and hotplug.d are finally removed
789 from the udev package.
795 Symlinks can have priorities now, the priority is assigned to the device
796 and specified with OPTIONS="link_priority=100". Devices with higher
797 priorities overwrite the symlinks of devices with lower priorities.
798 If the device that currently owns the link, goes away, the symlink
799 will be removed, and recreated, pointing to the next device with the
800 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
801 more reliable, if multiple devices contain the same metadata and overwrite
804 The dasd_id program is removed from the udev tree, and dasdinfo, with the
805 needed rules, are part of the s390-tools now.
807 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
808 we may get the scsi sysfs mess fixed some day, and this will only catch
809 the devices we are looking for.
811 USB serial numbers for storage devices have the target:lun now appended,
812 to make it possibble to distinguish broken multi-lun devices with all
813 the same SCSI identifiers.
815 Note: The extra "run_directory" which searches and executes stuff in
816 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
817 with the next release. Make sure, that you don't use it anymore, or
818 provides your own implementation of that inefficient stuff.
819 We are tired of reports about a "slow udev", because these directories
820 contain stuff, that runs with _every_ event, instead of using rules,
821 that run programs only for the matching events.
831 DRIVER== will match only for devices that actually have a real
832 driver. DRIVERS== must be used, if parent devices should be
833 included in the match.
835 Libvolume_id's "linux_raid" detection needed another fix.
843 Add additional check to volume_id detection of via_raid, cause
844 some company decided to put a matching pattern all over the empty
845 storage area of their music players.
849 Fix path_id for SAS devices.
853 The udev daemon can be started with --debug-trace now, which will
854 execute all events serialized to get a chance to catch a possible
855 action that crashes the box.
857 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
858 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
859 are excluded from the warning. Referencing parent attributes directly
860 may break when something in the kernel driver model changes. Udev will
861 just find the attribute by walking up the parent chain.
863 Udevtrigger now sorts the list of devices depending on the device
864 dependency, so a "usb" device is triggered after the parent "pci"
869 Revert persistent-storage ata-serial '_' '-' replacement.
875 Udevtrigger can now filter the list of devices to be triggered. Matches
876 for subsystems or sysfs attributes can be specified.
878 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
879 zero-sized files to avoid pointing to /sys and confuse broken tools which
880 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
883 The rules and scripts to create udev rules for persistent network
884 devices and optical drives are in the extras/rules_generator directory
885 now. If you use something similar, please consider replacing your own
886 version with this, to share the support effort. The rule_generator
887 installs its own rules into /etc/udev/rules.d.
889 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
890 the rule_generator depends on cdrom_id to be called in an earlier rule.
896 Renaming of some key names (the old names still work):
897 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
898 (The behavior of the key DRIVER will change soon in one of the next
899 releases, to match only the event device, please switch to DRIVERS
900 instead. If DRIVER is used, it will behave like DRIVERS, but an error
902 With the new key names, we have a more consistent and simpler scheme.
903 We can match the properties of the event device only, with: KERNEL,
904 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
905 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
906 longer mentioned in the man page and should be switched in the rule
909 ATTR{file}="value" can be used now, to write to a sysfs file of the
910 event device. Instead of:
911 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
913 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
915 All the PHYSDEV* keys are deprecated and will be removed from a
917 PHYDEVPATH - is the path of a parent device and should not be
919 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
920 matched with SUBSYSTEMS==
921 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
922 Newer kernels will have DRIVER in the environment,
923 for older kernels udev puts in. Class device will
924 no longer carry this property of a parent and
925 DRIVERS== can be used to match such a parent value.
926 Note that ENV{DRIVER} is only available for a few bus devices, where
927 the driver is already bound at device event time. On coldplug, the
928 events for a lot devices are already bound to a driver, and they will have
929 that value set. But on hotplug, at the time the kernel creates the device,
930 it can't know what driver may claim the device after that, therefore
931 in most cases it will be empty.
933 Failed events should now be re-triggered with:
934 udevtrigger --retry-failed.
935 Please switch to this command, so we keep the details of the /dev/.udev/failed/
936 files private to the udev tools. We may need to switch the current symlink
937 target, cause some obviously broken tools try to scan all files in /dev
938 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
939 million times. This takes ages on slow boxes.
941 The udevinfo attribute walk (-a) now works with giving a device node
942 name (-n) instead of a devpath (-p). The query now always works, also when
943 no database file was created by udev.
945 The built-in /etc/passwd /etc/group parser is removed, we always depend on
946 getpwnam() and getgrnam() now. One of the next releases will depend on
947 fnmatch() and may use getopt_long().
951 Bugfixes and small improvements.
955 Fix path_id for recent kernels.
961 Added support for swapping network interface names, by temporarily
962 renaming the device and wait for the target name to become free.
966 The built-in MODALIAS key and substitution is removed.
970 The binary firmware helper is replaced by the usual simple
971 shell script. Udevsend is removed from the tree.
979 Some more keys require the correct use of '==' and '=' depending
980 on the kind of operation beeing an assignment or a match. Rules
981 with invalid operations are skipped and logged to syslog. Please
982 test with udevtest if the parsing of your rules throws errors and
983 fix possibly broken rules.
987 Provide "udevsettle" to wait for all current udev events to finish.
988 It also watches the current kernel netlink queue by comparing the
989 even sequence number to make sure that there are no current pending
990 events that have not already arrived in the daemon.
994 Fix rule to skip persistent rules for removable IDE devices, which
995 also skipped optical IDE drives.
997 All *_id program are installed in /lib/udev/ by default now.
999 No binary is stripped anymore as this should be done in the
1000 packaging process and not at build time.
1002 libvolume_id is provided as a shared library now and vol_id is
1003 linked against it. Also one of the next HAL versions will require
1004 this library, and the HAL build process will also require the
1005 header file to be installed. The copy of the same code in HAL will
1006 be removed to have only a single copy left on the system.
1010 Add persistent links for SCSI tapes. The rules file is renamed
1011 to 60-persistent-storage.rules.
1013 Create persistent path for usb devices. Can be used for all sorts
1014 of devices that can't be distinguished by other properties like
1015 multiple identical keyboards and mice connected to the same box.
1017 Provide "udevtrigger" program to request events on coldplug. The
1018 shell script is much too slow with thousends of devices.
1022 Fix persistent disk rules to exclude removable IDE drives.
1024 Warn if %e, $modalias or MODALIAS is used.
1028 Fix queue export, which wasn't correct for subsequent add/remove
1029 events for the same device.
1033 Fix cramfs detection on big endian.
1035 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
1040 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
1041 attributes were only checked at the parent device that matched the
1042 by BUS requested subsystem. Fix it to also look at the device we
1043 received the event for.
1045 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
1050 Fix a bug where NAME="" would prevent RUN from beeing executed.
1052 RUN="/bin/program" does not longer automatically add the subsystem
1053 as the first parameter. This is from the days of /sbin/hotplug
1054 which is dead now and it's just confusing to need to add a space at
1055 the end of the program name to prevent this.
1056 If you use rules that need the subsystem as the first parameter,
1057 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
1058 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
1062 The udev man page has moved to udev(7) as it does not describe a command
1063 anymore. The programs udev, udevstart and udevsend are no longer installed
1064 by default and must be copied manually, if they should be installed or
1065 included in a package.
1067 Fix a bug where "ignore_device" could run earlier collected RUN keys before
1068 the ignore rule was applied.
1070 More preparation for future sysfs changes. usb_id and scsi_id no longer
1071 depend on a magic order of devices in the /devices chain. Specific devices
1072 should be requested by their subsytem.
1074 This will always find the scsi parent device without depending on a specific
1076 dev = sysfs_device_get(devpath);
1077 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
1079 The "device" link in the current sysfs layout will be automatically
1080 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
1081 parent in the devpath. If a device is requested by it's symlink, like all
1082 class devices in the new sysfs layout will look like, it gets automatically
1083 resolved and substituted with the real devpath and not the symlink path.
1086 A similar logic must be applied to _all_ sysfs users, including
1087 scripts, that search along parent devices in sysfs. The explicit use of
1088 the "device" link must be avoided. With the future sysfs layout all
1089 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
1090 back to the "class" or the "bus". The layout of the parent devices in
1091 /devices is not necessarily expected to be stable across kernel releases and
1092 searching for parents by their subsystem should make sysfs users tolerant
1093 for changed parent chains.
1097 Prepare udev to work with the experimental kernel patch, that moves
1098 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
1100 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
1101 moving the class devices to /sys/devices.
1103 Thanks again to Marco for help finding a hopefully nice compromise
1104 to make %b simpler and working again.
1108 Complete removal of libsysfs, replaced by simple helper functions
1109 which are much simpler and a bit faster. The udev daemon operatesentirely
1110 on event parameters and does not use sysfs for simple rules anymore.
1111 Please report any new bugs/problems, that may be caused by this big
1112 change. They will be fixed immediately.
1114 The enumeration format character '%e' is deprecated and will be
1115 removed sometimes from a future udev version. It never worked correctly
1116 outside of udevstart, so we can't use it with the new parallel
1117 coldplug. A simple enumeration is as useless as the devfs naming
1118 scheme, just get rid of both if you still use it.
1120 MODALIAS and $modalias is not needed and will be removed from one of
1121 the next udev versions, replace it in all rules with ENV{MODALIAS} or
1122 the sysfs "modalias" value.
1124 Thanks a lot to Marco for all his help on finding and fixing bugs.
1128 Let scsi_id request libata drive serial numbers from page 0x80.
1130 Renamed etc/udev/persistent.rules to persistent-disk.rules and
1131 added /dev/disk/by-name/* for device mapper device names.
1133 Removed %e from the man page. It never worked reliably outside
1134 of udevstart and udevstart is no longer recommended to use.
1138 Symlinks are now exported to the event environment. Hopefully it's no
1139 longer needed to run udevinfo from an event process, like it was
1140 mentioned on the hotplug list:
1141 UDEV [1134776873.702967] add@/block/sdb
1144 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
1148 Fix a problem if udevsend is used as the hotplug handler and tries to use
1149 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
1150 and this kind of problems will hopefully go away soon.
1154 All built-in logic to work around bad sysfs timing is removed with this
1155 version. The need to wait for sysfs files is almost fixed with a kernel
1156 version that doesn't work with this udev version anyway. Until we fix
1157 the timing of the "bus" link creation, the former integrated logic should
1158 be emulated by a rule placed before all other rules:
1159 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
1161 The option "udev_db" does no longer exist. All udev state will be in
1162 /$udev_root/.udev/ now, there is no longer an option to set this
1164 If the init script or something else used this value, just depend on
1165 this hardcoded path. But remember _all_content_ of this directory is
1166 still private to udev and can change at any time.
1168 Default location for rule sripts and helper programs is now: /lib/udev/.
1169 Everything that is not useful on the commandline should go into this
1170 directory. Some of the helpers in the extras folder are installed there
1171 now. The rules need to be changed, to find the helpers there.
1173 Also /lib/udev/devices is recommended as a directory where packages or
1174 the user can place real device nodes, which get copied over to /dev at
1175 every boot. This should replace the various solutions with custom config
1178 Udevsend does no longer start the udev daemon. This must be done with
1179 the init script that prepares /dev on tmpfs and creates the initial nodes,
1180 before starting the daemon.
1184 Silent a too verbose error logging for the old hotplug.d/ dev.d/
1187 The copy of klibc is removed. A systemwide installed version of klibc
1188 should be used to build a klibc udev now.
1192 NAME="" will not create any nodes, but execute RUN keys. To completely
1193 ignore an event the OPTION "ignore_device" should be used.
1195 After removal of the reorder queue, events with a TIMEOUT can be executed
1196 without any queuing now.
1200 Fixed bug in udevd, if inotify is not available. We depend on netlink
1201 uevents now, kernels without that event source will not work with that
1202 version of udev anymore.
1206 The rule parsing happens now in the daemon once at startup, all udev
1207 event processes inherit the already parsed rules from the daemon.
1208 It is shipped with SUSE10.0 and reduces heavily the system load at
1209 startup. The option to save precompiled rules and let the udev process
1210 pick the them up is removed, as it's no longer needed.
1212 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
1213 device. Libsysfs is changed to "translate" the requested link into the
1214 real device path, as it would happen with the hotplug event. Otherwise
1215 device removal and the udev database will not work.
1217 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
1220 A few improvements for vol_id, the filesytem probing code.
1224 Fix a stupid typo in extras/run_directory for "make install".
1226 scsi_id creates the temporary devnode now in /dev for usage with a
1227 non-writable /tmp directory.
1229 The uevent kernel socket buffer can carry app. 50.000 events now,
1230 let's see who can break this again. :)
1232 The upcoming kernel will have a new input driver core integration.
1233 Some class devices are now symlinks to the real device. libsysfs
1234 needs a fix for this to work correctly. Udevstart of older udev
1235 versions will _not_ create these devices!
1239 Fix a 'install' target in the Makefile, that prevents EXTRAS from
1244 A bunch of mostly trivial bugfixes. From now on no node name or
1245 symlink name can contain any character than plain whitelisted ascii
1246 characters or validated utf8 byte-streams. This is needed for the
1247 /dev/disk/by-label/* links, because we import untrusted data and
1248 export it to the filesystem.
1252 More bugfixes. If udevd was started from the kernel, we don't
1253 have stdin/stdout/stderr, which broke the forked tools in some
1258 Bugfix. udevstart event ordering was broken for a long time.
1259 The new run_program() uncovered it, because /dev/null was not
1260 available while we try to run external programs.
1261 Now udevstart should create it before we run anything.
1265 Minor bugfixes and some distro rules updates. If you don't have the
1266 persistent disk rules in /dev/disk/by-*/* on your distro, just
1267 grab it from here. :)
1271 We can use socket communication now to pass events from udev to
1273 RUN+="socket:/org/freedesktop/hal/udev_event"
1274 will pass the whole udev event to the HAL daemon without the need
1275 for a forked helper. (See ChangeLog for udevmonitor, as an example)
1279 Mostly bugfixes and see ChangeLog.
1281 The test for the existence of an environment value should be
1283 ENV{KEY}=="*" to ENV{KEY}=="?*"
1284 because "*" will not fail anymore, if the key does not exist or
1289 Bugfixes and a few tweaks described in the ChangeLog.
1293 Mostly a Bugfix release.
1295 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
1296 timing with custom rules.
1300 We changed the internal rule storage format. Our large rule files took
1301 2 MB of RAM, with the change we are down to 99kB.
1303 If the device-node has been created with default name and no symlink or
1304 options are to remenber, it is not longer stored in the udevdb. HAL will
1305 need to be updated to work correctly with that change.
1307 To overrride optimization flags, OPTFLAGS may be used now.
1315 Major changes happened with this release. The goal is to take over the
1316 complete kernel-event handling and provide a more efficient way to dispatch
1317 kernel events. Replacing most of the current shell script logic and the
1318 kernel forked helper with a netlink-daemon and a rule-based event handling.
1320 o udevd listens to netlink events now. The first valid netlink event
1321 will make udevd ignore any message from udevsend that contains a
1322 SEQNUM, to avoid duplicate events. The forked events can be disabled
1324 echo "" > /proc/sys/kernel/hotplug
1325 For full support, the broken input-subsytem needs to be fixed, not to
1326 bypass the driver core.
1328 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
1329 removed from udev itself and must be emulated by calling small
1330 helper binaries provided in the extras folder:
1331 make EXTRAS=extras/run_directory/
1332 will build udev_run_devd and udev_run_hotplugd, which can be called
1333 from a rule if needed:
1334 RUN+="/sbin/udev_run_hotplugd"
1335 The recommended way to handle this is to convert all the calls from
1336 the directories to explicit udev rules and get completely rid of the
1337 multiplexing. (To catch a ttyUSB event, you now no longer need to
1338 fork and exit 300 tty script instances you are not interested in, it
1339 is just one rule that matches exactly the device.)
1341 o udev handles now _all_ events not just events for class and block
1342 devices, this way it is possible to control the complete event
1343 behavior with udev rules. Especially useful for rules like:
1344 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
1346 o As used in the modalias rule, udev supports now textual
1347 substitution placeholder along with the usual format chars. This
1348 needs to be documented, for now it's only visible in udev_rules_parse.c.
1350 o The rule keys support now more operations. This is documented in the
1351 man page. It is possible to add values to list-keys like the SYMLINK
1352 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
1353 Also "final"-assignments are supported by using KEY:="value", which will
1354 prevent changing the key by any later rule.
1356 o kernel 2.6.12 has the "detached_state" attribute removed from
1357 sysfs, which was used to recognize sysfs population. We switched that
1358 to wait for the "bus" link, which is only available in kernels after 2.6.11.
1359 Running this udev version on older kernels may cause a short delay for
1362 o To provide infrastructure for persistent device naming, the id programs:
1363 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
1364 to export the probed data in environment key format:
1365 pim:~ # /sbin/ata_id --export /dev/hda
1366 ID_MODEL=HTS726060M9AT00
1367 ID_SERIAL=MRH401M4G6UM9B
1368 ID_REVISION=MH4OA6BA
1370 The following rules:
1371 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
1372 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
1375 kay@pim:~> tree /dev/disk
1378 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
1379 | `-- IBM-Memory_Key -> ../../sda
1381 | |-- swap -> ../../hda1
1382 | |-- date -> ../../sda1
1383 | `-- home -> ../../hda3
1385 |-- 2E08712B0870F2E7 -> ../../hda3
1386 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
1387 |-- E845-7A89 -> ../../sda1
1388 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
1390 The IMPORT= operation will import these keys in the environment and make
1391 it available for later PROGRAM= and RUN= executed programs. The keys are
1392 also stored in the udevdb and can be queried from there with one of the
1395 o A few binaries are silently added to the repository, which can be used
1396 to replay kernel events from initramfs instead of using coldplug. udevd
1397 can be instructed now to queue-up events while the stored events from
1398 initramfs are filled into the udevd-queue. This code is still under
1399 development and there is no documentation now besides the code itself.
1400 The additional binaries get compiled, but are not installed by default.
1402 o There is also a temporary fix for a performance problem where too many
1403 events happen in parallel and every event needs to parse the rules.
1404 udev can now read precompiled rules stored on disk. This is likely to be
1405 replaced by a more elegant solution in a future udev version.
1409 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
1410 Fix for libsysfs not to expect this file was added.
1414 All rules are applied now, but only the first matching rule with a NAME-key
1415 will be applied. All later rules with NAME-key are completely ignored. This
1416 way system supplied symlinks or permissions gets applied to user-defined
1420 Please check your rules setup, if you may need to add OPTIONS="last_rule"
1421 to some rules, to keep the old behavior.
1423 The rules are read on "remove"-events too. That makes is possible to match
1424 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
1425 instruct udev to ignore an event (OPTIONS="ignore_device").
1426 The new ACTION-key may be used to let a rule act only at a "remove"-event.
1428 The new RUN-key supports rule-based execution of programs after device-node
1429 handling. This is meant as a general replacement for the dev.d/-directories
1430 to give fine grained control over the execution of programs.
1432 The %s{}-sysfs format char replacement values are searched at any of the
1433 devices in the device chain now, not only at the class-device.
1435 We support log priority levels now. The value udev_log in udev.conf is used
1436 to determine what is printed to syslog. This makes it possible to
1437 run a version with compiled-in debug messages in a production environment
1438 which is sometimes needed to find a bug.
1439 It is still possible to supress the inclusion of _any_ syslog usage with
1440 USE_LOG=false to create the smallest possible binaries if needed.
1441 The configured udev_log value can be overridden with the environment variable
1446 Possible use of a system-wide klibc:
1447 make USE_KLIBC=true KLCC=/usr/bin/klcc all
1448 will link against an external klibc and our own version will be ignored.
1452 We support an unlimited count of symlinks now.
1454 If USE_STATIC=true is passed to a glibc build, we link statically and use
1455 a built-in userdb parser to resolve user and group names.
1457 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
1458 we walk up the chain of physical devices to find a match.
1460 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
1461 easy to skip certain attribute matches without composing rules with weird
1462 character class negations like:
1463 KERNEL="[!s][!c][!d]*"
1464 this can now be replaced with:
1466 The current simple '=' is still supported, and should work as it does today,
1467 but existing rules should be converted if possible, to be better readable.
1469 We have new ENV{}== key now, to match against a maximum of 5 environment
1472 udevstart is its own binary again, because we don't need co carry this araound
1473 with every forked event.
~ianmdlvl / elogind.git / blob