5 Persistent network naming rules are disabled inside of Qemu/KVM now.
7 New and updated keymaps.
9 Udev gets unconditionally enabled on systemd installations now. There
10 is no longer the need to to run 'systemctl enable udev.service'.
24 New and fixed keymaps.
26 Install systemd service files if applicable.
32 All distribution specific rules are removed from the udev source tree,
33 most of them are no longer needed. The Gentoo rules which allow to support
34 older kernel versions, which are not covered by the default rules anymore
35 has moved to rules/misc/30-kernel-compat.rules.
41 The option --debug-trace and the environemnt variable UDEVD_MAX_CHILDS=
42 was removed from udevd.
44 Udevd now checks the kernel commandline for the following variables:
45 udev.log-priority=<syslog priority>
46 udev.children-max=<maximum number of workers>
47 udev.exec-delay=<seconds to delay the execution of RUN=>
48 to help debuging coldplug setups where the loading of a kernel
49 module crashes the system.
51 The subdirectory in the source tree rules/packages has been renamed to
52 rules/arch, anc contains only architecture specific rules now.
62 Now the udev daemon itself, does on startup:
63 - copy the content of /lib/udev/devices to /dev
64 - create the standard symlinks like /dev/std{in,out,err},
65 /dev/core, /dev/fd, ...
66 - use static node information provided by kernel modules
67 and creates these nodes to allow module on-demand loading
68 - possibly apply permissions to all ststic nodes from udev
69 rules which are annotated to match a static node
71 The default mode for a device node is 0600 now to match the kernel
72 created devtmpfs defaults. If GROUP= is specified and no MODE= is
73 given the default will be 0660.
79 Udev now gradually starts to pass control over the primary device nodes
80 and their names to the kernel, and will in the end only manage the
81 permissions of the node, and possibly create additional symlinks.
82 As a first step NAME="" will be ignored, and NAME= setings with names
83 other than the kernel provided name will result in a logged warning.
84 Kernels that don't provide device names, or devtmpfs is not used, will
85 still work as they did before, but it is strongly recommended to use
86 only the same names for the primary device node as the recent kernel
87 provides for all devices.
91 Fix broken firmware loader search path.
97 "udevadm trigger" defaults to "change" events now instead of "add"
98 events. The "udev boot script" might need to add "--action=add" to
99 the trigger command if not already there, in case the initial coldplug
100 events are expected as "add" events.
102 The option "all_partitons" was removed from udev. This should not be
103 needed for usual hardware. Udev can not safely make assumptions
104 about non-existing partition major/minor numbers, and therefore no
105 longer provide this unreliable and unsafe option.
107 The option "ignore_remove" was removed from udev. With devtmpfs
108 udev passed control over device nodes to the kernel. This option
109 should not be needed, or can not work as advertised. Neither
110 udev nor the kernel will remove device nodes which are copied from
111 the /lib/udev/devices/ directory.
113 All "add|change" matches are replaced by "!remove" in the rules and
114 in the udev logic. All types of events will update possible symlinks
115 and permissions, only "remove" is handled special now.
117 The modem modeswitch extra was removed and the external usb_modeswitch
118 program should be used instead.
120 New and fixed keymaps.
130 Kernels with SYSFS_DEPRECATED=y are not supported since a while. Many users
131 depend on the current sysfs layout and the information not available in the
132 deprecated layout. All remaining support for the deprecated sysfs layout is
137 Fix for a possible endless loop in the new input_id program.
143 The option "ignore_device" does no longer exist. There is no way to
144 ignore an event, as libudev events can not be suppressed by rules.
145 It only prevented RUN keys from being executed, which results in an
146 inconsistent behavior in current setups.
148 BUS=, SYSFS{}=, ID= are long deprecated and should be SUBSYSTEM(S)=,
149 ATTR(S){}=, KERNEL(S)=. It will cause a warning once for every rule
152 The support for the deprecated IDE devices has been removed from the
153 default set of rules. Distros who still care about non-libata drivers
154 need to add the rules to the compat rules file.
156 The ID_CLASS property on input devices has been replaced by the more accurate
157 set of flags ID_INPUT_{KEYBOARD,KEY,MOUSE,TOUCHPAD,TABLET,JOYSTICK}. These are
158 determined by the new "input_id" prober now. Some devices, such as touchpads,
159 can have several classes. So if you previously had custom udev rules which e. g.
160 checked for ENV{ID_CLASS}=="kbd", you need to replace this with
161 ENV{ID_INPUT_KEYBOARD}=="?*".
167 To support DEVPATH strings larger than the maximum file name length, the
168 private udev database format has changed. If some software still reads the
169 private files in /dev/.udev/, which it shouldn't, now it's time to fix it.
170 Please do not port anything to the new format again, everything in /dev/.udev
171 is and always was private to udev, and may and will change any time without
174 Multiple devices claiming the same names in /dev are limited to symlinks
175 only now. Mixing identical symlink names and node names is not supported.
176 This reduces the amount of data in the database significantly.
178 NAME="%k" causes a warning now. It's is and always was completely superfluous.
179 It will break kernel supplied DEVNAMEs and therefore it needs to be removed
182 Most NAME= instructions got removed. Kernel 2.6.31 supplies the needed names
183 if they are not the default. To support older kernels, the NAME= rules need to
184 be added to the compat rules file.
186 Symlinks to udevadm with the old command names are no longer resolved to
187 the udevadm commands.
189 The udev-acl tool got adopted to changes in ConsoleKit. Version 0.4.1 is
192 The option "last_rule" does no longer exist. Its use breaks too many
193 things which expect to be run from independent later rules, and is an idication
194 that something needs to be fixed properly instead.
196 The gudev API is no longer marked as experimental,
197 G_UDEV_API_IS_SUBJECT_TO_CHANGE is no longer needed. The gudev introspection
198 is enabled by default now. Various projects already depend on introspection
199 information to bind dynamic languages to the gudev interfaces.
205 The udevadm trigger "--retry-failed" option, which is replaced since quite
206 a while by "--type=failed" is removed.
208 The failed tracking was not working at all for a few releases. The RUN
209 option "ignore_error" is replaced by a "fail_event_on_error" option, and the
210 default is not to track any failing RUN executions.
212 New keymaps, new modem, hid2hci updated.
216 Fix possible crash in udevd when worker processes are busy, rules are
217 changed at the same time, and workers get killed to reload the rules.
223 Properties set with ENV{.FOO}="bar" are marked private by starting the
224 name with a '.'. They will not be stored in the database, and not be
225 exported with the event.
227 Firmware files are looked up in:
228 /lib/firmware/updates/$(uname -r)
229 /lib/firmware/updates
230 /lib/firmware/$(uname -r)
234 ATA devices switched the property from ID_BUS=scsi to ID_BUS=ata.
235 ata_id, instead of scsi_id, is the default tool now for ATA devices.
241 The configure options have changed because another library needs to be
242 installed in a different location. Instead of exec_prefix and udev_prefix,
243 libdir, rootlibdir and libexecdir are used. The Details are explained in
246 Event processes now get re-used after they handled an event. This reduces
247 the number of forks and the pressure on the CPU significantly, because
248 cloned event processes no longer cause page faults in the main daemon.
249 After the events have settled, a few worker processes stay around for
250 future events, all others get cleaned up.
252 To be able to use signalfd(), udev depends on kernel version 2.6.25 now.
253 Also inotify support is mandatory now to run udev.
255 The format of the queue exported by the udev damon has changed. There is
256 no longer a /dev/.udev/queue/ directory. The current event queue can be
257 accessed with udevadm settle and libudedv.
259 Libudev does not have the unstable API header anymore. From now on,
260 incompatible changes will be handled by bumping the library major version.
262 To build udev from the git tree gtk-doc is needed now. The tarballs will
263 build without it and contain the pre-built documentation. An online copy
265 http://www.kernel.org/pub/linux/utils/kernel/hotplug/libudev/
267 The tools from the udev-extras repository have been merged into the main
268 udev repository. Some of the extras have larger external dependencies, and
269 they can be disabled with the configure switch --disable-extras.
275 The program vol_id and the library libvolume_id are removed from the
276 repository. Libvolume_id is merged with libblkid from the util-linux-ng
277 package. Persistent disk links for label and uuid depend on the
278 util-linux-ng version (2.15) of blkid now. Older versions of blkid
279 can not be used with udev.
281 Libudev allows to subscribe to udev events. To prevent unwanted messages
282 to be delivered, and waking up the subscribing process, a filter can be
283 installed, to drop messages inside a kernel socket filter. The filters
284 match on the <subsytem>:<devtype> properties of the device.
285 This is part of the ongoing effort to replace HAL, and switch current
286 users over to directly use libudev.
287 Libudev is still marked as experimental, and its interface might
288 eventually change if needed, but no major changes of the currently exported
289 interface are expected anymore, and a first stable release should happen
292 A too old kernel (2.6.21) or a kernel with CONFIG_SYSFS_DEPRECATED
293 is not supported since while and udevd will log an error message at
294 startup. It should still be able to boot-up, but advanced rules and system
295 services which depend on the information not available in the old sysfs
296 format will fail to work correctly.
298 DVB device naming is supplied by the kernel now. In case older kernels
299 need to be supported, the old shell script should be added to a compat
306 The processed udev events get send back to the netlink socket. Libudev
307 provides access to these events. This is work-in-progress, to replace
308 the DeviceKit daemon functionality directly with libudev. There are
309 upcoming kernel changes to allow non-root users to subcribe to these
316 "udevadm settle" now optionally accepts a range of events to wait for,
317 instead of waiting for "all" events.
323 The installed watch for block device metadata changes is now removed
324 during event hadling, because some (broken) tools may be called from udev
325 rules and (wrongly) open the device with write access. After the finished
326 event handling the watch is restored.
332 Device nodes can be watched for changes with inotify with OPTIONS="watch".
333 If closed after being opened for writing, a "change" uevent will occur.
334 /dev/disk/by-{label,uuid}/* symlinks will be automatically updated.
340 The udevadm test command has no longer a --force option, nodes and symlinks
341 are always updated with a test run now.
343 The udevd daemon can be started with --resolve-names=never to avoid all user
344 and group lookups (e.g. in cut-down systems) or --resolve-names=late to
345 lookup user and groups every time events are handled.
351 We are currently merging the Ubuntu rules in the udev default rules,
352 and get one step closer to provide a common Linux /dev setup, regarding
353 device names, symlinks, and default device permissions. On udev startup,
354 we now expect the following groups to be resolvable to their ids with
356 disk, cdrom, floppy, tape, audio, video, lp, tty, dialout, kmem.
357 LDAP setups need to make sure, that these groups are always resolvable at
358 bootup, with only the rootfs mounted, and without network access available.
360 Some systems may need to add some new, currently not used groups, or need
361 to add some users to new groups, but the cost of this change is minimal,
362 compared to the pain the current, rather random, differences between the
363 various distributions cause for upstream projects and third-party vendors.
365 In general, "normal" users who log into a machine should never be a member
366 of any such group, but the device-access should be managed by dynamic ACLs,
367 which get added and removed for the specific users on login/logout and
368 session activity/inactivity. These groups are only provided for custom setups,
369 and mainly system services, to allow proper privilege separation.
370 A video-streaming daemon uid would be a member of "audio" and "video", to get
371 access to the sound and video devices, but no "normal" user should ever belong
372 to the "audio" group, because he could listen to the built-in microphone with
373 any ssh-session established from the other side of the world.
375 /dev/serial/by-{id,path}/ now contains links for ttyUSB devices,
376 which do not depend on the kernel device name. As usual, unique
377 devices - only a single one per product connected, or a real
378 USB serial number in the device - are always found with the same
379 name in the by-id/ directory.
380 Completely identical devices may overwrite their names in by-id/
381 and can only be found reliably in the by-path/ directory. Devices
382 specified by by-path/ must not change their connection, like the
383 USB port number they are plugged in, to keep their name.
385 To support some advanced features, Linux 2.6.22 is the oldest supported
386 version now. The kernel config with enabled SYSFS_DEPRECATED is no longer
387 supported. Older kernels should still work, and devices nodes should be
388 reliably created, but some rules and libudev will not work correctly because
389 the old kernels do not provide the expected information or interfaces.
395 Fix for a possible segfault while swapping network interface names in udev
402 The group "video" is part of the default rules now.
406 Bugfix for kernels using SYSFS_DEPRECATED* option and finding parent
407 block devices in some cases. No common distro uses this option anymore,
408 and we do not get enough testing for this and recent udev versions. If
409 this option is not needed to run some old distro with a new kernel,
410 it should be disabled in the kernel config.
412 Bugfix for the $links substitution variable, which may crash if no links
413 are created. This should not happen in usual setups because we always
414 create /dev/{block,char}/ links.
416 The strings of the parsed rules, which are kept in memory, no longer
417 contain duplicate entries, or duplicate tails of strings. This, and the
418 new rules parsing/matching code reduces the total in-memory size of
419 a huge distro rule sets to 0.08 MB, compared to the 1.2MB of udev
422 The export of DEVTYPE=disk/partition got removed from the default
423 rules. This value is available from the kernel. The pnp shell script
424 modprobe hack is removed from the default rules. ACPI devices have _proper_
425 modalias support and take care of the same functionality.
426 Installations which support old kernels, but install current default
427 udev rules may want to add that to the compat rules file.
429 Libvolume_id now always probes for all known filesystems, and does not
430 stop at the first match. Some filesystems are marked as "exclusive probe",
431 and if any other filesytem type matches at the same time, libvolume_id
432 will, by default, not return any probing result. This is intended to prevent
433 mis-detection with conflicting left-over signatures found from earlier
434 file system formats. That way, we no longer depend on the probe-order
435 in case of multiple competing signatures. In some setups the kernel allows
436 to mount a volume with just the old filesystem signature still in place.
437 This may damage the new filesystem and cause data-loss, just by mounting
438 it. Because volume_id can not decide which one the correct signature is,
439 the wrong signatures need to be removed manually from the volume, or the
440 volume needs to be reformatted, to enable filesystem detection and possible
445 Fix segfault if compiled without optimization and dbg() does not get
446 compiled out and uses variables which are not available.
450 Bugfixes. (And maybe new bugs. :))
452 The rule matching engine got converted from a rule list to a token
453 array which reduced the in-memory rules representation of a full
454 featured distros with thousends of udev rules from 1.2MB to 0.12 MB.
455 Limits like 5 ENV and ATTR matches, and one single instance for most
456 other keys per rule are gone.
458 The NAME assignment is no longer special cased. If later rules assign
459 a NAME value again, the former value will be overwritten. As usual
460 for most other keys, the NAME value can be protected by doing a final
461 assignment with NAME:="<value>".
463 All udev code now uses libudev, which is also exported. The library
464 is still under development, marked as experimental, and its interface
465 may change as long as the DeviceKit integration is not finished.
467 Many thanks to Alan Jenkins for his continuous help, and finding and
468 optimizing some of the computing expensive parts.
474 Kernel devices and device nodes are connected now by reverse indizes in
475 /sys and /dev. A device number retrieved by a stat() or similar, the
476 kernel device directory can be found by looking up:
477 /sys/dev/{block,char}/<maj>:<min>
478 and the device node of the same device by looking up:
479 /dev/{block,char}/<maj>:<min>
483 Fix recently introduced bug, which caused a compilation without large
484 file support, where vol_id does not recognize raid signatures at the end
487 Firewire disks now create both, by-id/scsi-* and by-id/ieee-* links.
488 Seems some kernel versions prevent the creation of the ieee-* links,
489 so people used the scsi-* link which disappeared now.
491 More libudev work. Almost all udevadm functionality comes from libudev
494 udevadm trigger has a new option --type, which allows to trigger events
495 for "devices", for "subsystems", or "failed" devices. The old option
496 --retry-failed" still works, but is no longer mentioned in the man page.
502 The udevadm info --device-id-of-file= output has changed to use
503 the obvious format. Possible current users should use the --export
504 option which is not affected.
506 The old udev commands symlinks to udevadm are not installed, if
507 these symlinks are used, a warning is printed.
513 Optical drive's media is no longer probed for raid signatures,
514 reading the end of the device causes some devices to malfunction.
515 Also the offset of the last session found is used now to probe
518 The volume_id library got a major version number update to 1,
519 some deprecated functions are removed.
521 A shared library "libudev" gets installed now to provide access
522 to udev device information. DeviceKit, the successor of HAL, will
523 need this library to access the udev database and search sysfs for
525 The library is currently in an experimental state, also the API is
526 expected to change, as long as the DeviceKit integration is not
531 We use ./configure now. See INSTALL for details. Current
534 "/usr" - prefix for man pages, include files
536 "" - the root filesystem, prefix for libs and binaries
540 "lib" - directory name for libraries, not a path name
541 multilib 64bit systems may use "lib64" instead of "lib"
543 compile-in verbose debug messages
545 disable all logging and compile-out all log strings
547 link against SELInux libraries, to set the expected context
550 In the default rules, the group "disk" gets permissions 0660 instead
551 of 0640. One small step closer to unify distro rules. Some day, all
552 distros hopefully end up with the same set of rules.
554 No symlinks to udevadm are installed anymore, if they are still needed,
555 they should be provided by the package.
561 Default udev rules, which are not supposed to be edited by the user, should
562 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
563 the udev package and will be replaced with an update. Udev will pick up rule
565 /lib/udev/rules.d/ - default installed rules
566 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
567 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
568 It does not matter in which directory a rule file lives, all files are sorted
571 To help creating /dev/root, we have now:
572 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
575 In case the current --device-id-of-file is already used, please switch to
576 the --export format version, it saves the output parsing and the old
577 format will be changed to use ':' as a separator, like the format in the
582 Fix cdrom_id to properly recognize blank media.
588 Tape drive id-data is queried from /dev/bsg/* instead of the tape
589 nodes. This avoids rewinding tapes on open().
595 The symlinks udevcontrol and udevtrigger are no longer installed by
598 The scsi_id program does not depend on sysfs anymore. It can speak
599 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
600 data, which should solve some old problems with tape devices, where
601 we better do not open all tape device nodes to identify the device.
607 The cdrom_id program is replaced by an advanced version, which can
608 detect most common device types, and also properties of the inserted
609 media. This is part of moving some basic functionality from HAL into
610 udev (and the kernel).
616 The last WAIT_FOR_SYSFS rule is removed from the default rules.
618 The symlinks to udevadm for the debugging tools: udevmonitor and
619 udevtest are no longer created.
621 The symlinks to the udevadm man page for the old tool names are
624 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
625 should be prefixed with '@' to indicate that the path is not a
636 Udevstart is removed from the tree, it did not get installed for
637 a long time now, and is long replaced by trigger and settle.
643 All udev tools are merged into a single binary called udevadm.
644 The old names of the tools are built-in commands in udevadm now.
645 Symlinks to udevadm, with the names of the old tools, provide
646 the same functionality as the standalone tools. There is also
647 only a single udevadm.8 man page left for all tools.
649 Tools like mkinitramfs should be checked, if they need to include
650 udevadm in the list of files.
660 The etc/udev/rules.d/ directory now contains a default set of basic
661 udev rules. This initial version is the result of a rules file merge
662 of Fedora and openSUSE. For these both distros only a few specific
663 rules are left in their own file, named after the distro. Rules which
664 are optionally installed, because they are only valid for a specific
665 architecture, or rules for subsystems which are not always used are
666 in etc/udev/packages/.
672 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
673 actions by dynamically created rules.
675 SYMLINK=="<value>" matches agains the entries in the list of
676 currently defined symlinks. The links are not created in the
677 filesystem at that point in time, but the values can be matched.
679 RUN{ignore_error}+="<program>" will ignore any exit code from the
680 program and not record as a failed event.
686 Final merge of patches/features from the Ubuntu package.
692 Control characters in filesystem label strings are no longer silenty
693 removed, but hex-encoded, to be able to uniquely identify the device
694 by its symlink in /dev/disk/by-label/.
695 If libvolume_id is used by mount(8), LABEL= will work as expected,
696 if slashes or other characters are used in the label string.
698 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
699 can be specified now. The TEST key accepts an optional mode mask
700 TEST{0100}=="<is executable file>".
702 Scsi_id now supports a mode without expecting scsi-specific sysfs
703 entries to allow the extraction of cciss-device persistent properties.
709 In the future, we may see uuid's which are just simple character
710 strings (see the DDF Raid Specification). For that reason vol_id now
711 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
712 the creation of symlinks, the *_SAFE values ensure, that no control
713 or whitespace characters are used in the filename.
715 Possible users of libvolume_id, please use the volume_id_get_* functions.
716 The public struct will go away in a future release of the library.
722 Removal of useless extras/eventrecorder.sh.
732 The directory multiplexer for dev.d/ and hotplug.d are finally removed
733 from the udev package.
739 Symlinks can have priorities now, the priority is assigned to the device
740 and specified with OPTIONS="link_priority=100". Devices with higher
741 priorities overwrite the symlinks of devices with lower priorities.
742 If the device that currently owns the link, goes away, the symlink
743 will be removed, and recreated, pointing to the next device with the
744 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
745 more reliable, if multiple devices contain the same metadata and overwrite
748 The dasd_id program is removed from the udev tree, and dasdinfo, with the
749 needed rules, are part of the s390-tools now.
751 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
752 we may get the scsi sysfs mess fixed some day, and this will only catch
753 the devices we are looking for.
755 USB serial numbers for storage devices have the target:lun now appended,
756 to make it possibble to distinguish broken multi-lun devices with all
757 the same SCSI identifiers.
759 Note: The extra "run_directory" which searches and executes stuff in
760 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
761 with the next release. Make sure, that you don't use it anymore, or
762 provides your own implementation of that inefficient stuff.
763 We are tired of reports about a "slow udev", because these directories
764 contain stuff, that runs with _every_ event, instead of using rules,
765 that run programs only for the matching events.
775 DRIVER== will match only for devices that actually have a real
776 driver. DRIVERS== must be used, if parent devices should be
777 included in the match.
779 Libvolume_id's "linux_raid" detection needed another fix.
787 Add additional check to volume_id detection of via_raid, cause
788 some company decided to put a matching pattern all over the empty
789 storage area of their music players.
793 Fix path_id for SAS devices.
797 The udev daemon can be started with --debug-trace now, which will
798 execute all events serialized to get a chance to catch a possible
799 action that crashes the box.
801 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
802 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
803 are excluded from the warning. Referencing parent attributes directly
804 may break when something in the kernel driver model changes. Udev will
805 just find the attribute by walking up the parent chain.
807 Udevtrigger now sorts the list of devices depending on the device
808 dependency, so a "usb" device is triggered after the parent "pci"
813 Revert persistent-storage ata-serial '_' '-' replacement.
819 Udevtrigger can now filter the list of devices to be triggered. Matches
820 for subsystems or sysfs attributes can be specified.
822 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
823 zero-sized files to avoid pointing to /sys and confuse broken tools which
824 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
827 The rules and scripts to create udev rules for persistent network
828 devices and optical drives are in the extras/rules_generator directory
829 now. If you use something similar, please consider replacing your own
830 version with this, to share the support effort. The rule_generator
831 installs its own rules into /etc/udev/rules.d.
833 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
834 the rule_generator depends on cdrom_id to be called in an earlier rule.
840 Renaming of some key names (the old names still work):
841 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
842 (The behavior of the key DRIVER will change soon in one of the next
843 releases, to match only the event device, please switch to DRIVERS
844 instead. If DRIVER is used, it will behave like DRIVERS, but an error
846 With the new key names, we have a more consistent and simpler scheme.
847 We can match the properties of the event device only, with: KERNEL,
848 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
849 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
850 longer mentioned in the man page and should be switched in the rule
853 ATTR{file}="value" can be used now, to write to a sysfs file of the
854 event device. Instead of:
855 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
857 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
859 All the PHYSDEV* keys are deprecated and will be removed from a
861 PHYDEVPATH - is the path of a parent device and should not be
863 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
864 matched with SUBSYSTEMS==
865 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
866 Newer kernels will have DRIVER in the environment,
867 for older kernels udev puts in. Class device will
868 no longer carry this property of a parent and
869 DRIVERS== can be used to match such a parent value.
870 Note that ENV{DRIVER} is only available for a few bus devices, where
871 the driver is already bound at device event time. On coldplug, the
872 events for a lot devices are already bound to a driver, and they will have
873 that value set. But on hotplug, at the time the kernel creates the device,
874 it can't know what driver may claim the device after that, therefore
875 in most cases it will be empty.
877 Failed events should now be re-triggered with:
878 udevtrigger --retry-failed.
879 Please switch to this command, so we keep the details of the /dev/.udev/failed/
880 files private to the udev tools. We may need to switch the current symlink
881 target, cause some obviously broken tools try to scan all files in /dev
882 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
883 million times. This takes ages on slow boxes.
885 The udevinfo attribute walk (-a) now works with giving a device node
886 name (-n) instead of a devpath (-p). The query now always works, also when
887 no database file was created by udev.
889 The built-in /etc/passwd /etc/group parser is removed, we always depend on
890 getpwnam() and getgrnam() now. One of the next releases will depend on
891 fnmatch() and may use getopt_long().
895 Bugfixes and small improvements.
899 Fix path_id for recent kernels.
905 Added support for swapping network interface names, by temporarily
906 renaming the device and wait for the target name to become free.
910 The built-in MODALIAS key and substitution is removed.
914 The binary firmware helper is replaced by the usual simple
915 shell script. Udevsend is removed from the tree.
923 Some more keys require the correct use of '==' and '=' depending
924 on the kind of operation beeing an assignment or a match. Rules
925 with invalid operations are skipped and logged to syslog. Please
926 test with udevtest if the parsing of your rules throws errors and
927 fix possibly broken rules.
931 Provide "udevsettle" to wait for all current udev events to finish.
932 It also watches the current kernel netlink queue by comparing the
933 even sequence number to make sure that there are no current pending
934 events that have not already arrived in the daemon.
938 Fix rule to skip persistent rules for removable IDE devices, which
939 also skipped optical IDE drives.
941 All *_id program are installed in /lib/udev/ by default now.
943 No binary is stripped anymore as this should be done in the
944 packaging process and not at build time.
946 libvolume_id is provided as a shared library now and vol_id is
947 linked against it. Also one of the next HAL versions will require
948 this library, and the HAL build process will also require the
949 header file to be installed. The copy of the same code in HAL will
950 be removed to have only a single copy left on the system.
954 Add persistent links for SCSI tapes. The rules file is renamed
955 to 60-persistent-storage.rules.
957 Create persistent path for usb devices. Can be used for all sorts
958 of devices that can't be distinguished by other properties like
959 multiple identical keyboards and mice connected to the same box.
961 Provide "udevtrigger" program to request events on coldplug. The
962 shell script is much too slow with thousends of devices.
966 Fix persistent disk rules to exclude removable IDE drives.
968 Warn if %e, $modalias or MODALIAS is used.
972 Fix queue export, which wasn't correct for subsequent add/remove
973 events for the same device.
977 Fix cramfs detection on big endian.
979 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
984 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
985 attributes were only checked at the parent device that matched the
986 by BUS requested subsystem. Fix it to also look at the device we
987 received the event for.
989 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
994 Fix a bug where NAME="" would prevent RUN from beeing executed.
996 RUN="/bin/program" does not longer automatically add the subsystem
997 as the first parameter. This is from the days of /sbin/hotplug
998 which is dead now and it's just confusing to need to add a space at
999 the end of the program name to prevent this.
1000 If you use rules that need the subsystem as the first parameter,
1001 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
1002 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
1006 The udev man page has moved to udev(7) as it does not describe a command
1007 anymore. The programs udev, udevstart and udevsend are no longer installed
1008 by default and must be copied manually, if they should be installed or
1009 included in a package.
1011 Fix a bug where "ignore_device" could run earlier collected RUN keys before
1012 the ignore rule was applied.
1014 More preparation for future sysfs changes. usb_id and scsi_id no longer
1015 depend on a magic order of devices in the /devices chain. Specific devices
1016 should be requested by their subsytem.
1018 This will always find the scsi parent device without depending on a specific
1020 dev = sysfs_device_get(devpath);
1021 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
1023 The "device" link in the current sysfs layout will be automatically
1024 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
1025 parent in the devpath. If a device is requested by it's symlink, like all
1026 class devices in the new sysfs layout will look like, it gets automatically
1027 resolved and substituted with the real devpath and not the symlink path.
1030 A similar logic must be applied to _all_ sysfs users, including
1031 scripts, that search along parent devices in sysfs. The explicit use of
1032 the "device" link must be avoided. With the future sysfs layout all
1033 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
1034 back to the "class" or the "bus". The layout of the parent devices in
1035 /devices is not necessarily expected to be stable across kernel releases and
1036 searching for parents by their subsystem should make sysfs users tolerant
1037 for changed parent chains.
1041 Prepare udev to work with the experimental kernel patch, that moves
1042 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
1044 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
1045 moving the class devices to /sys/devices.
1047 Thanks again to Marco for help finding a hopefully nice compromise
1048 to make %b simpler and working again.
1052 Complete removal of libsysfs, replaced by simple helper functions
1053 which are much simpler and a bit faster. The udev daemon operatesentirely
1054 on event parameters and does not use sysfs for simple rules anymore.
1055 Please report any new bugs/problems, that may be caused by this big
1056 change. They will be fixed immediately.
1058 The enumeration format character '%e' is deprecated and will be
1059 removed sometimes from a future udev version. It never worked correctly
1060 outside of udevstart, so we can't use it with the new parallel
1061 coldplug. A simple enumeration is as useless as the devfs naming
1062 scheme, just get rid of both if you still use it.
1064 MODALIAS and $modalias is not needed and will be removed from one of
1065 the next udev versions, replace it in all rules with ENV{MODALIAS} or
1066 the sysfs "modalias" value.
1068 Thanks a lot to Marco for all his help on finding and fixing bugs.
1072 Let scsi_id request libata drive serial numbers from page 0x80.
1074 Renamed etc/udev/persistent.rules to persistent-disk.rules and
1075 added /dev/disk/by-name/* for device mapper device names.
1077 Removed %e from the man page. It never worked reliably outside
1078 of udevstart and udevstart is no longer recommended to use.
1082 Symlinks are now exported to the event environment. Hopefully it's no
1083 longer needed to run udevinfo from an event process, like it was
1084 mentioned on the hotplug list:
1085 UDEV [1134776873.702967] add@/block/sdb
1088 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
1092 Fix a problem if udevsend is used as the hotplug handler and tries to use
1093 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
1094 and this kind of problems will hopefully go away soon.
1098 All built-in logic to work around bad sysfs timing is removed with this
1099 version. The need to wait for sysfs files is almost fixed with a kernel
1100 version that doesn't work with this udev version anyway. Until we fix
1101 the timing of the "bus" link creation, the former integrated logic should
1102 be emulated by a rule placed before all other rules:
1103 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
1105 The option "udev_db" does no longer exist. All udev state will be in
1106 /$udev_root/.udev/ now, there is no longer an option to set this
1108 If the init script or something else used this value, just depend on
1109 this hardcoded path. But remember _all_content_ of this directory is
1110 still private to udev and can change at any time.
1112 Default location for rule sripts and helper programs is now: /lib/udev/.
1113 Everything that is not useful on the commandline should go into this
1114 directory. Some of the helpers in the extras folder are installed there
1115 now. The rules need to be changed, to find the helpers there.
1117 Also /lib/udev/devices is recommended as a directory where packages or
1118 the user can place real device nodes, which get copied over to /dev at
1119 every boot. This should replace the various solutions with custom config
1122 Udevsend does no longer start the udev daemon. This must be done with
1123 the init script that prepares /dev on tmpfs and creates the initial nodes,
1124 before starting the daemon.
1128 Silent a too verbose error logging for the old hotplug.d/ dev.d/
1131 The copy of klibc is removed. A systemwide installed version of klibc
1132 should be used to build a klibc udev now.
1136 NAME="" will not create any nodes, but execute RUN keys. To completely
1137 ignore an event the OPTION "ignore_device" should be used.
1139 After removal of the reorder queue, events with a TIMEOUT can be executed
1140 without any queuing now.
1144 Fixed bug in udevd, if inotify is not available. We depend on netlink
1145 uevents now, kernels without that event source will not work with that
1146 version of udev anymore.
1150 The rule parsing happens now in the daemon once at startup, all udev
1151 event processes inherit the already parsed rules from the daemon.
1152 It is shipped with SUSE10.0 and reduces heavily the system load at
1153 startup. The option to save precompiled rules and let the udev process
1154 pick the them up is removed, as it's no longer needed.
1156 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
1157 device. Libsysfs is changed to "translate" the requested link into the
1158 real device path, as it would happen with the hotplug event. Otherwise
1159 device removal and the udev database will not work.
1161 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
1164 A few improvements for vol_id, the filesytem probing code.
1168 Fix a stupid typo in extras/run_directory for "make install".
1170 scsi_id creates the temporary devnode now in /dev for usage with a
1171 non-writable /tmp directory.
1173 The uevent kernel socket buffer can carry app. 50.000 events now,
1174 let's see who can break this again. :)
1176 The upcoming kernel will have a new input driver core integration.
1177 Some class devices are now symlinks to the real device. libsysfs
1178 needs a fix for this to work correctly. Udevstart of older udev
1179 versions will _not_ create these devices!
1183 Fix a 'install' target in the Makefile, that prevents EXTRAS from
1188 A bunch of mostly trivial bugfixes. From now on no node name or
1189 symlink name can contain any character than plain whitelisted ascii
1190 characters or validated utf8 byte-streams. This is needed for the
1191 /dev/disk/by-label/* links, because we import untrusted data and
1192 export it to the filesystem.
1196 More bugfixes. If udevd was started from the kernel, we don't
1197 have stdin/stdout/stderr, which broke the forked tools in some
1202 Bugfix. udevstart event ordering was broken for a long time.
1203 The new run_program() uncovered it, because /dev/null was not
1204 available while we try to run external programs.
1205 Now udevstart should create it before we run anything.
1209 Minor bugfixes and some distro rules updates. If you don't have the
1210 persistent disk rules in /dev/disk/by-*/* on your distro, just
1211 grab it from here. :)
1215 We can use socket communication now to pass events from udev to
1217 RUN+="socket:/org/freedesktop/hal/udev_event"
1218 will pass the whole udev event to the HAL daemon without the need
1219 for a forked helper. (See ChangeLog for udevmonitor, as an example)
1223 Mostly bugfixes and see ChangeLog.
1225 The test for the existence of an environment value should be
1227 ENV{KEY}=="*" to ENV{KEY}=="?*"
1228 because "*" will not fail anymore, if the key does not exist or
1233 Bugfixes and a few tweaks described in the ChangeLog.
1237 Mostly a Bugfix release.
1239 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
1240 timing with custom rules.
1244 We changed the internal rule storage format. Our large rule files took
1245 2 MB of RAM, with the change we are down to 99kB.
1247 If the device-node has been created with default name and no symlink or
1248 options are to remenber, it is not longer stored in the udevdb. HAL will
1249 need to be updated to work correctly with that change.
1251 To overrride optimization flags, OPTFLAGS may be used now.
1259 Major changes happened with this release. The goal is to take over the
1260 complete kernel-event handling and provide a more efficient way to dispatch
1261 kernel events. Replacing most of the current shell script logic and the
1262 kernel forked helper with a netlink-daemon and a rule-based event handling.
1264 o udevd listens to netlink events now. The first valid netlink event
1265 will make udevd ignore any message from udevsend that contains a
1266 SEQNUM, to avoid duplicate events. The forked events can be disabled
1268 echo "" > /proc/sys/kernel/hotplug
1269 For full support, the broken input-subsytem needs to be fixed, not to
1270 bypass the driver core.
1272 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
1273 removed from udev itself and must be emulated by calling small
1274 helper binaries provided in the extras folder:
1275 make EXTRAS=extras/run_directory/
1276 will build udev_run_devd and udev_run_hotplugd, which can be called
1277 from a rule if needed:
1278 RUN+="/sbin/udev_run_hotplugd"
1279 The recommended way to handle this is to convert all the calls from
1280 the directories to explicit udev rules and get completely rid of the
1281 multiplexing. (To catch a ttyUSB event, you now no longer need to
1282 fork and exit 300 tty script instances you are not interested in, it
1283 is just one rule that matches exactly the device.)
1285 o udev handles now _all_ events not just events for class and block
1286 devices, this way it is possible to control the complete event
1287 behavior with udev rules. Especially useful for rules like:
1288 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
1290 o As used in the modalias rule, udev supports now textual
1291 substitution placeholder along with the usual format chars. This
1292 needs to be documented, for now it's only visible in udev_rules_parse.c.
1294 o The rule keys support now more operations. This is documented in the
1295 man page. It is possible to add values to list-keys like the SYMLINK
1296 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
1297 Also "final"-assignments are supported by using KEY:="value", which will
1298 prevent changing the key by any later rule.
1300 o kernel 2.6.12 has the "detached_state" attribute removed from
1301 sysfs, which was used to recognize sysfs population. We switched that
1302 to wait for the "bus" link, which is only available in kernels after 2.6.11.
1303 Running this udev version on older kernels may cause a short delay for
1306 o To provide infrastructure for persistent device naming, the id programs:
1307 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
1308 to export the probed data in environment key format:
1309 pim:~ # /sbin/ata_id --export /dev/hda
1310 ID_MODEL=HTS726060M9AT00
1311 ID_SERIAL=MRH401M4G6UM9B
1312 ID_REVISION=MH4OA6BA
1314 The following rules:
1315 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
1316 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
1319 kay@pim:~> tree /dev/disk
1322 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
1323 | `-- IBM-Memory_Key -> ../../sda
1325 | |-- swap -> ../../hda1
1326 | |-- date -> ../../sda1
1327 | `-- home -> ../../hda3
1329 |-- 2E08712B0870F2E7 -> ../../hda3
1330 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
1331 |-- E845-7A89 -> ../../sda1
1332 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
1334 The IMPORT= operation will import these keys in the environment and make
1335 it available for later PROGRAM= and RUN= executed programs. The keys are
1336 also stored in the udevdb and can be queried from there with one of the
1339 o A few binaries are silently added to the repository, which can be used
1340 to replay kernel events from initramfs instead of using coldplug. udevd
1341 can be instructed now to queue-up events while the stored events from
1342 initramfs are filled into the udevd-queue. This code is still under
1343 development and there is no documentation now besides the code itself.
1344 The additional binaries get compiled, but are not installed by default.
1346 o There is also a temporary fix for a performance problem where too many
1347 events happen in parallel and every event needs to parse the rules.
1348 udev can now read precompiled rules stored on disk. This is likely to be
1349 replaced by a more elegant solution in a future udev version.
1353 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
1354 Fix for libsysfs not to expect this file was added.
1358 All rules are applied now, but only the first matching rule with a NAME-key
1359 will be applied. All later rules with NAME-key are completely ignored. This
1360 way system supplied symlinks or permissions gets applied to user-defined
1364 Please check your rules setup, if you may need to add OPTIONS="last_rule"
1365 to some rules, to keep the old behavior.
1367 The rules are read on "remove"-events too. That makes is possible to match
1368 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
1369 instruct udev to ignore an event (OPTIONS="ignore_device").
1370 The new ACTION-key may be used to let a rule act only at a "remove"-event.
1372 The new RUN-key supports rule-based execution of programs after device-node
1373 handling. This is meant as a general replacement for the dev.d/-directories
1374 to give fine grained control over the execution of programs.
1376 The %s{}-sysfs format char replacement values are searched at any of the
1377 devices in the device chain now, not only at the class-device.
1379 We support log priority levels now. The value udev_log in udev.conf is used
1380 to determine what is printed to syslog. This makes it possible to
1381 run a version with compiled-in debug messages in a production environment
1382 which is sometimes needed to find a bug.
1383 It is still possible to supress the inclusion of _any_ syslog usage with
1384 USE_LOG=false to create the smallest possible binaries if needed.
1385 The configured udev_log value can be overridden with the environment variable
1390 Possible use of a system-wide klibc:
1391 make USE_KLIBC=true KLCC=/usr/bin/klcc all
1392 will link against an external klibc and our own version will be ignored.
1396 We support an unlimited count of symlinks now.
1398 If USE_STATIC=true is passed to a glibc build, we link statically and use
1399 a built-in userdb parser to resolve user and group names.
1401 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
1402 we walk up the chain of physical devices to find a match.
1404 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
1405 easy to skip certain attribute matches without composing rules with weird
1406 character class negations like:
1407 KERNEL="[!s][!c][!d]*"
1408 this can now be replaced with:
1410 The current simple '=' is still supported, and should work as it does today,
1411 but existing rules should be converted if possible, to be better readable.
1413 We have new ENV{}== key now, to match against a maximum of 5 environment
1416 udevstart is its own binary again, because we don't need co carry this araound
1417 with every forked event.