5 The option --debug-trace and the environemnt variable UDEVD_MAX_CHILDS=
6 was removed from udevd.
8 Udevd now parses the kernel commandline for the following variables:
9 udev.log-priority=<syslog priority>
10 udev.children-max=<maximum number of workers>
11 udev.exec-delay=<seconds to delay the execution of RUN=>
12 to help debuging coldplug setups where the loading of a kernel
13 module crashes the system.
15 The subdirectory in the source tree rules/packages has been renamed to
16 rules/arch, anc contains only architecture specific rules now.
26 Now the udev daemon itself, does on startup:
27 - copy the content of /lib/udev/devices to /dev
28 - create the standard symlinks like /dev/std{in,out,err},
29 /dev/core, /dev/fd, ...
30 - use static node information provided by kernel modules
31 and creates these nodes to allow module on-demand loading
32 - possibly apply permissions to all ststic nodes from udev
33 rules which are annotated to match a static node
35 The default mode for a device node is 0600 now to match the kernel
36 created devtmpfs defaults. If GROUP= is specified and no MODE= is
37 given the default will be 0660.
43 Udev now gradually starts to pass control over the primary device nodes
44 and their names to the kernel, and will in the end only manage the
45 permissions of the node, and possibly create additional symlinks.
46 As a first step NAME="" will be ignored, and NAME= setings with names
47 other than the kernel provided name will result in a logged warning.
48 Kernels that don't provide device names, or devtmpfs is not used, will
49 still work as they did before, but it is strongly recommended to use
50 only the same names for the primary device node as the recent kernel
51 provides for all devices.
55 Fix broken firmware loader search path.
61 "udevadm trigger" defaults to "change" events now instead of "add"
62 events. The "udev boot script" might need to add "--action=add" to
63 the trigger command if not already there, in case the initial coldplug
64 events are expected as "add" events.
66 The option "all_partitons" was removed from udev. This should not be
67 needed for usual hardware. Udev can not safely make assumptions
68 about non-existing partition major/minor numbers, and therefore no
69 longer provide this unreliable and unsafe option.
71 The option "ignore_remove" was removed from udev. With devtmpfs
72 udev passed control over device nodes to the kernel. This option
73 should not be needed, or can not work as advertised. Neither
74 udev nor the kernel will remove device nodes which are copied from
75 the /lib/udev/devices/ directory.
77 All "add|change" matches are replaced by "!remove" in the rules and
78 in the udev logic. All types of events will update possible symlinks
79 and permissions, only "remove" is handled special now.
81 The modem modeswitch extra was removed and the external usb_modeswitch
82 program should be used instead.
84 New and fixed keymaps.
94 Kernels with SYSFS_DEPRECATED=y are not supported since a while. Many users
95 depend on the current sysfs layout and the information not available in the
96 deprecated layout. All remaining support for the deprecated sysfs layout is
101 Fix for a possible endless loop in the new input_id program.
107 The option "ignore_device" does no longer exist. There is no way to
108 ignore an event, as libudev events can not be suppressed by rules.
109 It only prevented RUN keys from being executed, which results in an
110 inconsistent behavior in current setups.
112 BUS=, SYSFS{}=, ID= are long deprecated and should be SUBSYSTEM(S)=,
113 ATTR(S){}=, KERNEL(S)=. It will cause a warning once for every rule
116 The support for the deprecated IDE devices has been removed from the
117 default set of rules. Distros who still care about non-libata drivers
118 need to add the rules to the compat rules file.
120 The ID_CLASS property on input devices has been replaced by the more accurate
121 set of flags ID_INPUT_{KEYBOARD,KEY,MOUSE,TOUCHPAD,TABLET,JOYSTICK}. These are
122 determined by the new "input_id" prober now. Some devices, such as touchpads,
123 can have several classes. So if you previously had custom udev rules which e. g.
124 checked for ENV{ID_CLASS}=="kbd", you need to replace this with
125 ENV{ID_INPUT_KEYBOARD}=="?*".
131 To support DEVPATH strings larger than the maximum file name length, the
132 private udev database format has changed. If some software still reads the
133 private files in /dev/.udev/, which it shouldn't, now it's time to fix it.
134 Please do not port anything to the new format again, everything in /dev/.udev
135 is and always was private to udev, and may and will change any time without
138 Multiple devices claiming the same names in /dev are limited to symlinks
139 only now. Mixing identical symlink names and node names is not supported.
140 This reduces the amount of data in the database significantly.
142 NAME="%k" causes a warning now. It's is and always was completely superfluous.
143 It will break kernel supplied DEVNAMEs and therefore it needs to be removed
146 Most NAME= instructions got removed. Kernel 2.6.31 supplies the needed names
147 if they are not the default. To support older kernels, the NAME= rules need to
148 be added to the compat rules file.
150 Symlinks to udevadm with the old command names are no longer resolved to
151 the udevadm commands.
153 The udev-acl tool got adopted to changes in ConsoleKit. Version 0.4.1 is
156 The option "last_rule" does no longer exist. Its use breaks too many
157 things which expect to be run from independent later rules, and is an idication
158 that something needs to be fixed properly instead.
160 The gudev API is no longer marked as experimental,
161 G_UDEV_API_IS_SUBJECT_TO_CHANGE is no longer needed. The gudev introspection
162 is enabled by default now. Various projects already depend on introspection
163 information to bind dynamic languages to the gudev interfaces.
169 The udevadm trigger "--retry-failed" option, which is replaced since quite
170 a while by "--type=failed" is removed.
172 The failed tracking was not working at all for a few releases. The RUN
173 option "ignore_error" is replaced by a "fail_event_on_error" option, and the
174 default is not to track any failing RUN executions.
176 New keymaps, new modem, hid2hci updated.
180 Fix possible crash in udevd when worker processes are busy, rules are
181 changed at the same time, and workers get killed to reload the rules.
187 Properties set with ENV{.FOO}="bar" are marked private by starting the
188 name with a '.'. They will not be stored in the database, and not be
189 exported with the event.
191 Firmware files are looked up in:
192 /lib/firmware/updates/$(uname -r)
193 /lib/firmware/updates
194 /lib/firmware/$(uname -r)
198 ATA devices switched the property from ID_BUS=scsi to ID_BUS=ata.
199 ata_id, instead of scsi_id, is the default tool now for ATA devices.
205 The configure options have changed because another library needs to be
206 installed in a different location. Instead of exec_prefix and udev_prefix,
207 libdir, rootlibdir and libexecdir are used. The Details are explained in
210 Event processes now get re-used after they handled an event. This reduces
211 the number of forks and the pressure on the CPU significantly, because
212 cloned event processes no longer cause page faults in the main daemon.
213 After the events have settled, a few worker processes stay around for
214 future events, all others get cleaned up.
216 To be able to use signalfd(), udev depends on kernel version 2.6.25 now.
217 Also inotify support is mandatory now to run udev.
219 The format of the queue exported by the udev damon has changed. There is
220 no longer a /dev/.udev/queue/ directory. The current event queue can be
221 accessed with udevadm settle and libudedv.
223 Libudev does not have the unstable API header anymore. From now on,
224 incompatible changes will be handled by bumping the library major version.
226 To build udev from the git tree gtk-doc is needed now. The tarballs will
227 build without it and contain the pre-built documentation. An online copy
229 http://www.kernel.org/pub/linux/utils/kernel/hotplug/libudev/
231 The tools from the udev-extras repository have been merged into the main
232 udev repository. Some of the extras have larger external dependencies, and
233 they can be disabled with the configure switch --disable-extras.
239 The program vol_id and the library libvolume_id are removed from the
240 repository. Libvolume_id is merged with libblkid from the util-linux-ng
241 package. Persistent disk links for label and uuid depend on the
242 util-linux-ng version (2.15) of blkid now. Older versions of blkid
243 can not be used with udev.
245 Libudev allows to subscribe to udev events. To prevent unwanted messages
246 to be delivered, and waking up the subscribing process, a filter can be
247 installed, to drop messages inside a kernel socket filter. The filters
248 match on the <subsytem>:<devtype> properties of the device.
249 This is part of the ongoing effort to replace HAL, and switch current
250 users over to directly use libudev.
251 Libudev is still marked as experimental, and its interface might
252 eventually change if needed, but no major changes of the currently exported
253 interface are expected anymore, and a first stable release should happen
256 A too old kernel (2.6.21) or a kernel with CONFIG_SYSFS_DEPRECATED
257 is not supported since while and udevd will log an error message at
258 startup. It should still be able to boot-up, but advanced rules and system
259 services which depend on the information not available in the old sysfs
260 format will fail to work correctly.
262 DVB device naming is supplied by the kernel now. In case older kernels
263 need to be supported, the old shell script should be added to a compat
270 The processed udev events get send back to the netlink socket. Libudev
271 provides access to these events. This is work-in-progress, to replace
272 the DeviceKit daemon functionality directly with libudev. There are
273 upcoming kernel changes to allow non-root users to subcribe to these
280 "udevadm settle" now optionally accepts a range of events to wait for,
281 instead of waiting for "all" events.
287 The installed watch for block device metadata changes is now removed
288 during event hadling, because some (broken) tools may be called from udev
289 rules and (wrongly) open the device with write access. After the finished
290 event handling the watch is restored.
296 Device nodes can be watched for changes with inotify with OPTIONS="watch".
297 If closed after being opened for writing, a "change" uevent will occur.
298 /dev/disk/by-{label,uuid}/* symlinks will be automatically updated.
304 The udevadm test command has no longer a --force option, nodes and symlinks
305 are always updated with a test run now.
307 The udevd daemon can be started with --resolve-names=never to avoid all user
308 and group lookups (e.g. in cut-down systems) or --resolve-names=late to
309 lookup user and groups every time events are handled.
315 We are currently merging the Ubuntu rules in the udev default rules,
316 and get one step closer to provide a common Linux /dev setup, regarding
317 device names, symlinks, and default device permissions. On udev startup,
318 we now expect the following groups to be resolvable to their ids with
320 disk, cdrom, floppy, tape, audio, video, lp, tty, dialout, kmem.
321 LDAP setups need to make sure, that these groups are always resolvable at
322 bootup, with only the rootfs mounted, and without network access available.
324 Some systems may need to add some new, currently not used groups, or need
325 to add some users to new groups, but the cost of this change is minimal,
326 compared to the pain the current, rather random, differences between the
327 various distributions cause for upstream projects and third-party vendors.
329 In general, "normal" users who log into a machine should never be a member
330 of any such group, but the device-access should be managed by dynamic ACLs,
331 which get added and removed for the specific users on login/logout and
332 session activity/inactivity. These groups are only provided for custom setups,
333 and mainly system services, to allow proper privilege separation.
334 A video-streaming daemon uid would be a member of "audio" and "video", to get
335 access to the sound and video devices, but no "normal" user should ever belong
336 to the "audio" group, because he could listen to the built-in microphone with
337 any ssh-session established from the other side of the world.
339 /dev/serial/by-{id,path}/ now contains links for ttyUSB devices,
340 which do not depend on the kernel device name. As usual, unique
341 devices - only a single one per product connected, or a real
342 USB serial number in the device - are always found with the same
343 name in the by-id/ directory.
344 Completely identical devices may overwrite their names in by-id/
345 and can only be found reliably in the by-path/ directory. Devices
346 specified by by-path/ must not change their connection, like the
347 USB port number they are plugged in, to keep their name.
349 To support some advanced features, Linux 2.6.22 is the oldest supported
350 version now. The kernel config with enabled SYSFS_DEPRECATED is no longer
351 supported. Older kernels should still work, and devices nodes should be
352 reliably created, but some rules and libudev will not work correctly because
353 the old kernels do not provide the expected information or interfaces.
359 Fix for a possible segfault while swapping network interface names in udev
366 The group "video" is part of the default rules now.
370 Bugfix for kernels using SYSFS_DEPRECATED* option and finding parent
371 block devices in some cases. No common distro uses this option anymore,
372 and we do not get enough testing for this and recent udev versions. If
373 this option is not needed to run some old distro with a new kernel,
374 it should be disabled in the kernel config.
376 Bugfix for the $links substitution variable, which may crash if no links
377 are created. This should not happen in usual setups because we always
378 create /dev/{block,char}/ links.
380 The strings of the parsed rules, which are kept in memory, no longer
381 contain duplicate entries, or duplicate tails of strings. This, and the
382 new rules parsing/matching code reduces the total in-memory size of
383 a huge distro rule sets to 0.08 MB, compared to the 1.2MB of udev
386 The export of DEVTYPE=disk/partition got removed from the default
387 rules. This value is available from the kernel. The pnp shell script
388 modprobe hack is removed from the default rules. ACPI devices have _proper_
389 modalias support and take care of the same functionality.
390 Installations which support old kernels, but install current default
391 udev rules may want to add that to the compat rules file.
393 Libvolume_id now always probes for all known filesystems, and does not
394 stop at the first match. Some filesystems are marked as "exclusive probe",
395 and if any other filesytem type matches at the same time, libvolume_id
396 will, by default, not return any probing result. This is intended to prevent
397 mis-detection with conflicting left-over signatures found from earlier
398 file system formats. That way, we no longer depend on the probe-order
399 in case of multiple competing signatures. In some setups the kernel allows
400 to mount a volume with just the old filesystem signature still in place.
401 This may damage the new filesystem and cause data-loss, just by mounting
402 it. Because volume_id can not decide which one the correct signature is,
403 the wrong signatures need to be removed manually from the volume, or the
404 volume needs to be reformatted, to enable filesystem detection and possible
409 Fix segfault if compiled without optimization and dbg() does not get
410 compiled out and uses variables which are not available.
414 Bugfixes. (And maybe new bugs. :))
416 The rule matching engine got converted from a rule list to a token
417 array which reduced the in-memory rules representation of a full
418 featured distros with thousends of udev rules from 1.2MB to 0.12 MB.
419 Limits like 5 ENV and ATTR matches, and one single instance for most
420 other keys per rule are gone.
422 The NAME assignment is no longer special cased. If later rules assign
423 a NAME value again, the former value will be overwritten. As usual
424 for most other keys, the NAME value can be protected by doing a final
425 assignment with NAME:="<value>".
427 All udev code now uses libudev, which is also exported. The library
428 is still under development, marked as experimental, and its interface
429 may change as long as the DeviceKit integration is not finished.
431 Many thanks to Alan Jenkins for his continuous help, and finding and
432 optimizing some of the computing expensive parts.
438 Kernel devices and device nodes are connected now by reverse indizes in
439 /sys and /dev. A device number retrieved by a stat() or similar, the
440 kernel device directory can be found by looking up:
441 /sys/dev/{block,char}/<maj>:<min>
442 and the device node of the same device by looking up:
443 /dev/{block,char}/<maj>:<min>
447 Fix recently introduced bug, which caused a compilation without large
448 file support, where vol_id does not recognize raid signatures at the end
451 Firewire disks now create both, by-id/scsi-* and by-id/ieee-* links.
452 Seems some kernel versions prevent the creation of the ieee-* links,
453 so people used the scsi-* link which disappeared now.
455 More libudev work. Almost all udevadm functionality comes from libudev
458 udevadm trigger has a new option --type, which allows to trigger events
459 for "devices", for "subsystems", or "failed" devices. The old option
460 --retry-failed" still works, but is no longer mentioned in the man page.
466 The udevadm info --device-id-of-file= output has changed to use
467 the obvious format. Possible current users should use the --export
468 option which is not affected.
470 The old udev commands symlinks to udevadm are not installed, if
471 these symlinks are used, a warning is printed.
477 Optical drive's media is no longer probed for raid signatures,
478 reading the end of the device causes some devices to malfunction.
479 Also the offset of the last session found is used now to probe
482 The volume_id library got a major version number update to 1,
483 some deprecated functions are removed.
485 A shared library "libudev" gets installed now to provide access
486 to udev device information. DeviceKit, the successor of HAL, will
487 need this library to access the udev database and search sysfs for
489 The library is currently in an experimental state, also the API is
490 expected to change, as long as the DeviceKit integration is not
495 We use ./configure now. See INSTALL for details. Current
498 "/usr" - prefix for man pages, include files
500 "" - the root filesystem, prefix for libs and binaries
504 "lib" - directory name for libraries, not a path name
505 multilib 64bit systems may use "lib64" instead of "lib"
507 compile-in verbose debug messages
509 disable all logging and compile-out all log strings
511 link against SELInux libraries, to set the expected context
514 In the default rules, the group "disk" gets permissions 0660 instead
515 of 0640. One small step closer to unify distro rules. Some day, all
516 distros hopefully end up with the same set of rules.
518 No symlinks to udevadm are installed anymore, if they are still needed,
519 they should be provided by the package.
525 Default udev rules, which are not supposed to be edited by the user, should
526 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
527 the udev package and will be replaced with an update. Udev will pick up rule
529 /lib/udev/rules.d/ - default installed rules
530 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
531 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
532 It does not matter in which directory a rule file lives, all files are sorted
535 To help creating /dev/root, we have now:
536 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
539 In case the current --device-id-of-file is already used, please switch to
540 the --export format version, it saves the output parsing and the old
541 format will be changed to use ':' as a separator, like the format in the
546 Fix cdrom_id to properly recognize blank media.
552 Tape drive id-data is queried from /dev/bsg/* instead of the tape
553 nodes. This avoids rewinding tapes on open().
559 The symlinks udevcontrol and udevtrigger are no longer installed by
562 The scsi_id program does not depend on sysfs anymore. It can speak
563 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
564 data, which should solve some old problems with tape devices, where
565 we better do not open all tape device nodes to identify the device.
571 The cdrom_id program is replaced by an advanced version, which can
572 detect most common device types, and also properties of the inserted
573 media. This is part of moving some basic functionality from HAL into
574 udev (and the kernel).
580 The last WAIT_FOR_SYSFS rule is removed from the default rules.
582 The symlinks to udevadm for the debugging tools: udevmonitor and
583 udevtest are no longer created.
585 The symlinks to the udevadm man page for the old tool names are
588 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
589 should be prefixed with '@' to indicate that the path is not a
600 Udevstart is removed from the tree, it did not get installed for
601 a long time now, and is long replaced by trigger and settle.
607 All udev tools are merged into a single binary called udevadm.
608 The old names of the tools are built-in commands in udevadm now.
609 Symlinks to udevadm, with the names of the old tools, provide
610 the same functionality as the standalone tools. There is also
611 only a single udevadm.8 man page left for all tools.
613 Tools like mkinitramfs should be checked, if they need to include
614 udevadm in the list of files.
624 The etc/udev/rules.d/ directory now contains a default set of basic
625 udev rules. This initial version is the result of a rules file merge
626 of Fedora and openSUSE. For these both distros only a few specific
627 rules are left in their own file, named after the distro. Rules which
628 are optionally installed, because they are only valid for a specific
629 architecture, or rules for subsystems which are not always used are
630 in etc/udev/packages/.
636 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
637 actions by dynamically created rules.
639 SYMLINK=="<value>" matches agains the entries in the list of
640 currently defined symlinks. The links are not created in the
641 filesystem at that point in time, but the values can be matched.
643 RUN{ignore_error}+="<program>" will ignore any exit code from the
644 program and not record as a failed event.
650 Final merge of patches/features from the Ubuntu package.
656 Control characters in filesystem label strings are no longer silenty
657 removed, but hex-encoded, to be able to uniquely identify the device
658 by its symlink in /dev/disk/by-label/.
659 If libvolume_id is used by mount(8), LABEL= will work as expected,
660 if slashes or other characters are used in the label string.
662 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
663 can be specified now. The TEST key accepts an optional mode mask
664 TEST{0100}=="<is executable file>".
666 Scsi_id now supports a mode without expecting scsi-specific sysfs
667 entries to allow the extraction of cciss-device persistent properties.
673 In the future, we may see uuid's which are just simple character
674 strings (see the DDF Raid Specification). For that reason vol_id now
675 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
676 the creation of symlinks, the *_SAFE values ensure, that no control
677 or whitespace characters are used in the filename.
679 Possible users of libvolume_id, please use the volume_id_get_* functions.
680 The public struct will go away in a future release of the library.
686 Removal of useless extras/eventrecorder.sh.
696 The directory multiplexer for dev.d/ and hotplug.d are finally removed
697 from the udev package.
703 Symlinks can have priorities now, the priority is assigned to the device
704 and specified with OPTIONS="link_priority=100". Devices with higher
705 priorities overwrite the symlinks of devices with lower priorities.
706 If the device that currently owns the link, goes away, the symlink
707 will be removed, and recreated, pointing to the next device with the
708 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
709 more reliable, if multiple devices contain the same metadata and overwrite
712 The dasd_id program is removed from the udev tree, and dasdinfo, with the
713 needed rules, are part of the s390-tools now.
715 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
716 we may get the scsi sysfs mess fixed some day, and this will only catch
717 the devices we are looking for.
719 USB serial numbers for storage devices have the target:lun now appended,
720 to make it possibble to distinguish broken multi-lun devices with all
721 the same SCSI identifiers.
723 Note: The extra "run_directory" which searches and executes stuff in
724 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
725 with the next release. Make sure, that you don't use it anymore, or
726 provides your own implementation of that inefficient stuff.
727 We are tired of reports about a "slow udev", because these directories
728 contain stuff, that runs with _every_ event, instead of using rules,
729 that run programs only for the matching events.
739 DRIVER== will match only for devices that actually have a real
740 driver. DRIVERS== must be used, if parent devices should be
741 included in the match.
743 Libvolume_id's "linux_raid" detection needed another fix.
751 Add additional check to volume_id detection of via_raid, cause
752 some company decided to put a matching pattern all over the empty
753 storage area of their music players.
757 Fix path_id for SAS devices.
761 The udev daemon can be started with --debug-trace now, which will
762 execute all events serialized to get a chance to catch a possible
763 action that crashes the box.
765 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
766 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
767 are excluded from the warning. Referencing parent attributes directly
768 may break when something in the kernel driver model changes. Udev will
769 just find the attribute by walking up the parent chain.
771 Udevtrigger now sorts the list of devices depending on the device
772 dependency, so a "usb" device is triggered after the parent "pci"
777 Revert persistent-storage ata-serial '_' '-' replacement.
783 Udevtrigger can now filter the list of devices to be triggered. Matches
784 for subsystems or sysfs attributes can be specified.
786 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
787 zero-sized files to avoid pointing to /sys and confuse broken tools which
788 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
791 The rules and scripts to create udev rules for persistent network
792 devices and optical drives are in the extras/rules_generator directory
793 now. If you use something similar, please consider replacing your own
794 version with this, to share the support effort. The rule_generator
795 installs its own rules into /etc/udev/rules.d.
797 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
798 the rule_generator depends on cdrom_id to be called in an earlier rule.
804 Renaming of some key names (the old names still work):
805 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
806 (The behavior of the key DRIVER will change soon in one of the next
807 releases, to match only the event device, please switch to DRIVERS
808 instead. If DRIVER is used, it will behave like DRIVERS, but an error
810 With the new key names, we have a more consistent and simpler scheme.
811 We can match the properties of the event device only, with: KERNEL,
812 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
813 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
814 longer mentioned in the man page and should be switched in the rule
817 ATTR{file}="value" can be used now, to write to a sysfs file of the
818 event device. Instead of:
819 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
821 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
823 All the PHYSDEV* keys are deprecated and will be removed from a
825 PHYDEVPATH - is the path of a parent device and should not be
827 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
828 matched with SUBSYSTEMS==
829 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
830 Newer kernels will have DRIVER in the environment,
831 for older kernels udev puts in. Class device will
832 no longer carry this property of a parent and
833 DRIVERS== can be used to match such a parent value.
834 Note that ENV{DRIVER} is only available for a few bus devices, where
835 the driver is already bound at device event time. On coldplug, the
836 events for a lot devices are already bound to a driver, and they will have
837 that value set. But on hotplug, at the time the kernel creates the device,
838 it can't know what driver may claim the device after that, therefore
839 in most cases it will be empty.
841 Failed events should now be re-triggered with:
842 udevtrigger --retry-failed.
843 Please switch to this command, so we keep the details of the /dev/.udev/failed/
844 files private to the udev tools. We may need to switch the current symlink
845 target, cause some obviously broken tools try to scan all files in /dev
846 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
847 million times. This takes ages on slow boxes.
849 The udevinfo attribute walk (-a) now works with giving a device node
850 name (-n) instead of a devpath (-p). The query now always works, also when
851 no database file was created by udev.
853 The built-in /etc/passwd /etc/group parser is removed, we always depend on
854 getpwnam() and getgrnam() now. One of the next releases will depend on
855 fnmatch() and may use getopt_long().
859 Bugfixes and small improvements.
863 Fix path_id for recent kernels.
869 Added support for swapping network interface names, by temporarily
870 renaming the device and wait for the target name to become free.
874 The built-in MODALIAS key and substitution is removed.
878 The binary firmware helper is replaced by the usual simple
879 shell script. Udevsend is removed from the tree.
887 Some more keys require the correct use of '==' and '=' depending
888 on the kind of operation beeing an assignment or a match. Rules
889 with invalid operations are skipped and logged to syslog. Please
890 test with udevtest if the parsing of your rules throws errors and
891 fix possibly broken rules.
895 Provide "udevsettle" to wait for all current udev events to finish.
896 It also watches the current kernel netlink queue by comparing the
897 even sequence number to make sure that there are no current pending
898 events that have not already arrived in the daemon.
902 Fix rule to skip persistent rules for removable IDE devices, which
903 also skipped optical IDE drives.
905 All *_id program are installed in /lib/udev/ by default now.
907 No binary is stripped anymore as this should be done in the
908 packaging process and not at build time.
910 libvolume_id is provided as a shared library now and vol_id is
911 linked against it. Also one of the next HAL versions will require
912 this library, and the HAL build process will also require the
913 header file to be installed. The copy of the same code in HAL will
914 be removed to have only a single copy left on the system.
918 Add persistent links for SCSI tapes. The rules file is renamed
919 to 60-persistent-storage.rules.
921 Create persistent path for usb devices. Can be used for all sorts
922 of devices that can't be distinguished by other properties like
923 multiple identical keyboards and mice connected to the same box.
925 Provide "udevtrigger" program to request events on coldplug. The
926 shell script is much too slow with thousends of devices.
930 Fix persistent disk rules to exclude removable IDE drives.
932 Warn if %e, $modalias or MODALIAS is used.
936 Fix queue export, which wasn't correct for subsequent add/remove
937 events for the same device.
941 Fix cramfs detection on big endian.
943 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
948 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
949 attributes were only checked at the parent device that matched the
950 by BUS requested subsystem. Fix it to also look at the device we
951 received the event for.
953 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
958 Fix a bug where NAME="" would prevent RUN from beeing executed.
960 RUN="/bin/program" does not longer automatically add the subsystem
961 as the first parameter. This is from the days of /sbin/hotplug
962 which is dead now and it's just confusing to need to add a space at
963 the end of the program name to prevent this.
964 If you use rules that need the subsystem as the first parameter,
965 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
966 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
970 The udev man page has moved to udev(7) as it does not describe a command
971 anymore. The programs udev, udevstart and udevsend are no longer installed
972 by default and must be copied manually, if they should be installed or
973 included in a package.
975 Fix a bug where "ignore_device" could run earlier collected RUN keys before
976 the ignore rule was applied.
978 More preparation for future sysfs changes. usb_id and scsi_id no longer
979 depend on a magic order of devices in the /devices chain. Specific devices
980 should be requested by their subsytem.
982 This will always find the scsi parent device without depending on a specific
984 dev = sysfs_device_get(devpath);
985 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
987 The "device" link in the current sysfs layout will be automatically
988 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
989 parent in the devpath. If a device is requested by it's symlink, like all
990 class devices in the new sysfs layout will look like, it gets automatically
991 resolved and substituted with the real devpath and not the symlink path.
994 A similar logic must be applied to _all_ sysfs users, including
995 scripts, that search along parent devices in sysfs. The explicit use of
996 the "device" link must be avoided. With the future sysfs layout all
997 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
998 back to the "class" or the "bus". The layout of the parent devices in
999 /devices is not necessarily expected to be stable across kernel releases and
1000 searching for parents by their subsystem should make sysfs users tolerant
1001 for changed parent chains.
1005 Prepare udev to work with the experimental kernel patch, that moves
1006 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
1008 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
1009 moving the class devices to /sys/devices.
1011 Thanks again to Marco for help finding a hopefully nice compromise
1012 to make %b simpler and working again.
1016 Complete removal of libsysfs, replaced by simple helper functions
1017 which are much simpler and a bit faster. The udev daemon operatesentirely
1018 on event parameters and does not use sysfs for simple rules anymore.
1019 Please report any new bugs/problems, that may be caused by this big
1020 change. They will be fixed immediately.
1022 The enumeration format character '%e' is deprecated and will be
1023 removed sometimes from a future udev version. It never worked correctly
1024 outside of udevstart, so we can't use it with the new parallel
1025 coldplug. A simple enumeration is as useless as the devfs naming
1026 scheme, just get rid of both if you still use it.
1028 MODALIAS and $modalias is not needed and will be removed from one of
1029 the next udev versions, replace it in all rules with ENV{MODALIAS} or
1030 the sysfs "modalias" value.
1032 Thanks a lot to Marco for all his help on finding and fixing bugs.
1036 Let scsi_id request libata drive serial numbers from page 0x80.
1038 Renamed etc/udev/persistent.rules to persistent-disk.rules and
1039 added /dev/disk/by-name/* for device mapper device names.
1041 Removed %e from the man page. It never worked reliably outside
1042 of udevstart and udevstart is no longer recommended to use.
1046 Symlinks are now exported to the event environment. Hopefully it's no
1047 longer needed to run udevinfo from an event process, like it was
1048 mentioned on the hotplug list:
1049 UDEV [1134776873.702967] add@/block/sdb
1052 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
1056 Fix a problem if udevsend is used as the hotplug handler and tries to use
1057 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
1058 and this kind of problems will hopefully go away soon.
1062 All built-in logic to work around bad sysfs timing is removed with this
1063 version. The need to wait for sysfs files is almost fixed with a kernel
1064 version that doesn't work with this udev version anyway. Until we fix
1065 the timing of the "bus" link creation, the former integrated logic should
1066 be emulated by a rule placed before all other rules:
1067 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
1069 The option "udev_db" does no longer exist. All udev state will be in
1070 /$udev_root/.udev/ now, there is no longer an option to set this
1072 If the init script or something else used this value, just depend on
1073 this hardcoded path. But remember _all_content_ of this directory is
1074 still private to udev and can change at any time.
1076 Default location for rule sripts and helper programs is now: /lib/udev/.
1077 Everything that is not useful on the commandline should go into this
1078 directory. Some of the helpers in the extras folder are installed there
1079 now. The rules need to be changed, to find the helpers there.
1081 Also /lib/udev/devices is recommended as a directory where packages or
1082 the user can place real device nodes, which get copied over to /dev at
1083 every boot. This should replace the various solutions with custom config
1086 Udevsend does no longer start the udev daemon. This must be done with
1087 the init script that prepares /dev on tmpfs and creates the initial nodes,
1088 before starting the daemon.
1092 Silent a too verbose error logging for the old hotplug.d/ dev.d/
1095 The copy of klibc is removed. A systemwide installed version of klibc
1096 should be used to build a klibc udev now.
1100 NAME="" will not create any nodes, but execute RUN keys. To completely
1101 ignore an event the OPTION "ignore_device" should be used.
1103 After removal of the reorder queue, events with a TIMEOUT can be executed
1104 without any queuing now.
1108 Fixed bug in udevd, if inotify is not available. We depend on netlink
1109 uevents now, kernels without that event source will not work with that
1110 version of udev anymore.
1114 The rule parsing happens now in the daemon once at startup, all udev
1115 event processes inherit the already parsed rules from the daemon.
1116 It is shipped with SUSE10.0 and reduces heavily the system load at
1117 startup. The option to save precompiled rules and let the udev process
1118 pick the them up is removed, as it's no longer needed.
1120 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
1121 device. Libsysfs is changed to "translate" the requested link into the
1122 real device path, as it would happen with the hotplug event. Otherwise
1123 device removal and the udev database will not work.
1125 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
1128 A few improvements for vol_id, the filesytem probing code.
1132 Fix a stupid typo in extras/run_directory for "make install".
1134 scsi_id creates the temporary devnode now in /dev for usage with a
1135 non-writable /tmp directory.
1137 The uevent kernel socket buffer can carry app. 50.000 events now,
1138 let's see who can break this again. :)
1140 The upcoming kernel will have a new input driver core integration.
1141 Some class devices are now symlinks to the real device. libsysfs
1142 needs a fix for this to work correctly. Udevstart of older udev
1143 versions will _not_ create these devices!
1147 Fix a 'install' target in the Makefile, that prevents EXTRAS from
1152 A bunch of mostly trivial bugfixes. From now on no node name or
1153 symlink name can contain any character than plain whitelisted ascii
1154 characters or validated utf8 byte-streams. This is needed for the
1155 /dev/disk/by-label/* links, because we import untrusted data and
1156 export it to the filesystem.
1160 More bugfixes. If udevd was started from the kernel, we don't
1161 have stdin/stdout/stderr, which broke the forked tools in some
1166 Bugfix. udevstart event ordering was broken for a long time.
1167 The new run_program() uncovered it, because /dev/null was not
1168 available while we try to run external programs.
1169 Now udevstart should create it before we run anything.
1173 Minor bugfixes and some distro rules updates. If you don't have the
1174 persistent disk rules in /dev/disk/by-*/* on your distro, just
1175 grab it from here. :)
1179 We can use socket communication now to pass events from udev to
1181 RUN+="socket:/org/freedesktop/hal/udev_event"
1182 will pass the whole udev event to the HAL daemon without the need
1183 for a forked helper. (See ChangeLog for udevmonitor, as an example)
1187 Mostly bugfixes and see ChangeLog.
1189 The test for the existence of an environment value should be
1191 ENV{KEY}=="*" to ENV{KEY}=="?*"
1192 because "*" will not fail anymore, if the key does not exist or
1197 Bugfixes and a few tweaks described in the ChangeLog.
1201 Mostly a Bugfix release.
1203 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
1204 timing with custom rules.
1208 We changed the internal rule storage format. Our large rule files took
1209 2 MB of RAM, with the change we are down to 99kB.
1211 If the device-node has been created with default name and no symlink or
1212 options are to remenber, it is not longer stored in the udevdb. HAL will
1213 need to be updated to work correctly with that change.
1215 To overrride optimization flags, OPTFLAGS may be used now.
1223 Major changes happened with this release. The goal is to take over the
1224 complete kernel-event handling and provide a more efficient way to dispatch
1225 kernel events. Replacing most of the current shell script logic and the
1226 kernel forked helper with a netlink-daemon and a rule-based event handling.
1228 o udevd listens to netlink events now. The first valid netlink event
1229 will make udevd ignore any message from udevsend that contains a
1230 SEQNUM, to avoid duplicate events. The forked events can be disabled
1232 echo "" > /proc/sys/kernel/hotplug
1233 For full support, the broken input-subsytem needs to be fixed, not to
1234 bypass the driver core.
1236 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
1237 removed from udev itself and must be emulated by calling small
1238 helper binaries provided in the extras folder:
1239 make EXTRAS=extras/run_directory/
1240 will build udev_run_devd and udev_run_hotplugd, which can be called
1241 from a rule if needed:
1242 RUN+="/sbin/udev_run_hotplugd"
1243 The recommended way to handle this is to convert all the calls from
1244 the directories to explicit udev rules and get completely rid of the
1245 multiplexing. (To catch a ttyUSB event, you now no longer need to
1246 fork and exit 300 tty script instances you are not interested in, it
1247 is just one rule that matches exactly the device.)
1249 o udev handles now _all_ events not just events for class and block
1250 devices, this way it is possible to control the complete event
1251 behavior with udev rules. Especially useful for rules like:
1252 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
1254 o As used in the modalias rule, udev supports now textual
1255 substitution placeholder along with the usual format chars. This
1256 needs to be documented, for now it's only visible in udev_rules_parse.c.
1258 o The rule keys support now more operations. This is documented in the
1259 man page. It is possible to add values to list-keys like the SYMLINK
1260 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
1261 Also "final"-assignments are supported by using KEY:="value", which will
1262 prevent changing the key by any later rule.
1264 o kernel 2.6.12 has the "detached_state" attribute removed from
1265 sysfs, which was used to recognize sysfs population. We switched that
1266 to wait for the "bus" link, which is only available in kernels after 2.6.11.
1267 Running this udev version on older kernels may cause a short delay for
1270 o To provide infrastructure for persistent device naming, the id programs:
1271 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
1272 to export the probed data in environment key format:
1273 pim:~ # /sbin/ata_id --export /dev/hda
1274 ID_MODEL=HTS726060M9AT00
1275 ID_SERIAL=MRH401M4G6UM9B
1276 ID_REVISION=MH4OA6BA
1278 The following rules:
1279 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
1280 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
1283 kay@pim:~> tree /dev/disk
1286 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
1287 | `-- IBM-Memory_Key -> ../../sda
1289 | |-- swap -> ../../hda1
1290 | |-- date -> ../../sda1
1291 | `-- home -> ../../hda3
1293 |-- 2E08712B0870F2E7 -> ../../hda3
1294 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
1295 |-- E845-7A89 -> ../../sda1
1296 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
1298 The IMPORT= operation will import these keys in the environment and make
1299 it available for later PROGRAM= and RUN= executed programs. The keys are
1300 also stored in the udevdb and can be queried from there with one of the
1303 o A few binaries are silently added to the repository, which can be used
1304 to replay kernel events from initramfs instead of using coldplug. udevd
1305 can be instructed now to queue-up events while the stored events from
1306 initramfs are filled into the udevd-queue. This code is still under
1307 development and there is no documentation now besides the code itself.
1308 The additional binaries get compiled, but are not installed by default.
1310 o There is also a temporary fix for a performance problem where too many
1311 events happen in parallel and every event needs to parse the rules.
1312 udev can now read precompiled rules stored on disk. This is likely to be
1313 replaced by a more elegant solution in a future udev version.
1317 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
1318 Fix for libsysfs not to expect this file was added.
1322 All rules are applied now, but only the first matching rule with a NAME-key
1323 will be applied. All later rules with NAME-key are completely ignored. This
1324 way system supplied symlinks or permissions gets applied to user-defined
1328 Please check your rules setup, if you may need to add OPTIONS="last_rule"
1329 to some rules, to keep the old behavior.
1331 The rules are read on "remove"-events too. That makes is possible to match
1332 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
1333 instruct udev to ignore an event (OPTIONS="ignore_device").
1334 The new ACTION-key may be used to let a rule act only at a "remove"-event.
1336 The new RUN-key supports rule-based execution of programs after device-node
1337 handling. This is meant as a general replacement for the dev.d/-directories
1338 to give fine grained control over the execution of programs.
1340 The %s{}-sysfs format char replacement values are searched at any of the
1341 devices in the device chain now, not only at the class-device.
1343 We support log priority levels now. The value udev_log in udev.conf is used
1344 to determine what is printed to syslog. This makes it possible to
1345 run a version with compiled-in debug messages in a production environment
1346 which is sometimes needed to find a bug.
1347 It is still possible to supress the inclusion of _any_ syslog usage with
1348 USE_LOG=false to create the smallest possible binaries if needed.
1349 The configured udev_log value can be overridden with the environment variable
1354 Possible use of a system-wide klibc:
1355 make USE_KLIBC=true KLCC=/usr/bin/klcc all
1356 will link against an external klibc and our own version will be ignored.
1360 We support an unlimited count of symlinks now.
1362 If USE_STATIC=true is passed to a glibc build, we link statically and use
1363 a built-in userdb parser to resolve user and group names.
1365 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
1366 we walk up the chain of physical devices to find a match.
1368 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
1369 easy to skip certain attribute matches without composing rules with weird
1370 character class negations like:
1371 KERNEL="[!s][!c][!d]*"
1372 this can now be replaced with:
1374 The current simple '=' is still supported, and should work as it does today,
1375 but existing rules should be converted if possible, to be better readable.
1377 We have new ENV{}== key now, to match against a maximum of 5 environment
1380 udevstart is its own binary again, because we don't need co carry this araound
1381 with every forked event.