9 The option --debug-trace and the environemnt variable UDEVD_MAX_CHILDS=
10 was removed from udevd.
12 Udevd now checks the kernel commandline for the following variables:
13 udev.log-priority=<syslog priority>
14 udev.children-max=<maximum number of workers>
15 udev.exec-delay=<seconds to delay the execution of RUN=>
16 to help debuging coldplug setups where the loading of a kernel
17 module crashes the system.
19 The subdirectory in the source tree rules/packages has been renamed to
20 rules/arch, anc contains only architecture specific rules now.
30 Now the udev daemon itself, does on startup:
31 - copy the content of /lib/udev/devices to /dev
32 - create the standard symlinks like /dev/std{in,out,err},
33 /dev/core, /dev/fd, ...
34 - use static node information provided by kernel modules
35 and creates these nodes to allow module on-demand loading
36 - possibly apply permissions to all ststic nodes from udev
37 rules which are annotated to match a static node
39 The default mode for a device node is 0600 now to match the kernel
40 created devtmpfs defaults. If GROUP= is specified and no MODE= is
41 given the default will be 0660.
47 Udev now gradually starts to pass control over the primary device nodes
48 and their names to the kernel, and will in the end only manage the
49 permissions of the node, and possibly create additional symlinks.
50 As a first step NAME="" will be ignored, and NAME= setings with names
51 other than the kernel provided name will result in a logged warning.
52 Kernels that don't provide device names, or devtmpfs is not used, will
53 still work as they did before, but it is strongly recommended to use
54 only the same names for the primary device node as the recent kernel
55 provides for all devices.
59 Fix broken firmware loader search path.
65 "udevadm trigger" defaults to "change" events now instead of "add"
66 events. The "udev boot script" might need to add "--action=add" to
67 the trigger command if not already there, in case the initial coldplug
68 events are expected as "add" events.
70 The option "all_partitons" was removed from udev. This should not be
71 needed for usual hardware. Udev can not safely make assumptions
72 about non-existing partition major/minor numbers, and therefore no
73 longer provide this unreliable and unsafe option.
75 The option "ignore_remove" was removed from udev. With devtmpfs
76 udev passed control over device nodes to the kernel. This option
77 should not be needed, or can not work as advertised. Neither
78 udev nor the kernel will remove device nodes which are copied from
79 the /lib/udev/devices/ directory.
81 All "add|change" matches are replaced by "!remove" in the rules and
82 in the udev logic. All types of events will update possible symlinks
83 and permissions, only "remove" is handled special now.
85 The modem modeswitch extra was removed and the external usb_modeswitch
86 program should be used instead.
88 New and fixed keymaps.
98 Kernels with SYSFS_DEPRECATED=y are not supported since a while. Many users
99 depend on the current sysfs layout and the information not available in the
100 deprecated layout. All remaining support for the deprecated sysfs layout is
105 Fix for a possible endless loop in the new input_id program.
111 The option "ignore_device" does no longer exist. There is no way to
112 ignore an event, as libudev events can not be suppressed by rules.
113 It only prevented RUN keys from being executed, which results in an
114 inconsistent behavior in current setups.
116 BUS=, SYSFS{}=, ID= are long deprecated and should be SUBSYSTEM(S)=,
117 ATTR(S){}=, KERNEL(S)=. It will cause a warning once for every rule
120 The support for the deprecated IDE devices has been removed from the
121 default set of rules. Distros who still care about non-libata drivers
122 need to add the rules to the compat rules file.
124 The ID_CLASS property on input devices has been replaced by the more accurate
125 set of flags ID_INPUT_{KEYBOARD,KEY,MOUSE,TOUCHPAD,TABLET,JOYSTICK}. These are
126 determined by the new "input_id" prober now. Some devices, such as touchpads,
127 can have several classes. So if you previously had custom udev rules which e. g.
128 checked for ENV{ID_CLASS}=="kbd", you need to replace this with
129 ENV{ID_INPUT_KEYBOARD}=="?*".
135 To support DEVPATH strings larger than the maximum file name length, the
136 private udev database format has changed. If some software still reads the
137 private files in /dev/.udev/, which it shouldn't, now it's time to fix it.
138 Please do not port anything to the new format again, everything in /dev/.udev
139 is and always was private to udev, and may and will change any time without
142 Multiple devices claiming the same names in /dev are limited to symlinks
143 only now. Mixing identical symlink names and node names is not supported.
144 This reduces the amount of data in the database significantly.
146 NAME="%k" causes a warning now. It's is and always was completely superfluous.
147 It will break kernel supplied DEVNAMEs and therefore it needs to be removed
150 Most NAME= instructions got removed. Kernel 2.6.31 supplies the needed names
151 if they are not the default. To support older kernels, the NAME= rules need to
152 be added to the compat rules file.
154 Symlinks to udevadm with the old command names are no longer resolved to
155 the udevadm commands.
157 The udev-acl tool got adopted to changes in ConsoleKit. Version 0.4.1 is
160 The option "last_rule" does no longer exist. Its use breaks too many
161 things which expect to be run from independent later rules, and is an idication
162 that something needs to be fixed properly instead.
164 The gudev API is no longer marked as experimental,
165 G_UDEV_API_IS_SUBJECT_TO_CHANGE is no longer needed. The gudev introspection
166 is enabled by default now. Various projects already depend on introspection
167 information to bind dynamic languages to the gudev interfaces.
173 The udevadm trigger "--retry-failed" option, which is replaced since quite
174 a while by "--type=failed" is removed.
176 The failed tracking was not working at all for a few releases. The RUN
177 option "ignore_error" is replaced by a "fail_event_on_error" option, and the
178 default is not to track any failing RUN executions.
180 New keymaps, new modem, hid2hci updated.
184 Fix possible crash in udevd when worker processes are busy, rules are
185 changed at the same time, and workers get killed to reload the rules.
191 Properties set with ENV{.FOO}="bar" are marked private by starting the
192 name with a '.'. They will not be stored in the database, and not be
193 exported with the event.
195 Firmware files are looked up in:
196 /lib/firmware/updates/$(uname -r)
197 /lib/firmware/updates
198 /lib/firmware/$(uname -r)
202 ATA devices switched the property from ID_BUS=scsi to ID_BUS=ata.
203 ata_id, instead of scsi_id, is the default tool now for ATA devices.
209 The configure options have changed because another library needs to be
210 installed in a different location. Instead of exec_prefix and udev_prefix,
211 libdir, rootlibdir and libexecdir are used. The Details are explained in
214 Event processes now get re-used after they handled an event. This reduces
215 the number of forks and the pressure on the CPU significantly, because
216 cloned event processes no longer cause page faults in the main daemon.
217 After the events have settled, a few worker processes stay around for
218 future events, all others get cleaned up.
220 To be able to use signalfd(), udev depends on kernel version 2.6.25 now.
221 Also inotify support is mandatory now to run udev.
223 The format of the queue exported by the udev damon has changed. There is
224 no longer a /dev/.udev/queue/ directory. The current event queue can be
225 accessed with udevadm settle and libudedv.
227 Libudev does not have the unstable API header anymore. From now on,
228 incompatible changes will be handled by bumping the library major version.
230 To build udev from the git tree gtk-doc is needed now. The tarballs will
231 build without it and contain the pre-built documentation. An online copy
233 http://www.kernel.org/pub/linux/utils/kernel/hotplug/libudev/
235 The tools from the udev-extras repository have been merged into the main
236 udev repository. Some of the extras have larger external dependencies, and
237 they can be disabled with the configure switch --disable-extras.
243 The program vol_id and the library libvolume_id are removed from the
244 repository. Libvolume_id is merged with libblkid from the util-linux-ng
245 package. Persistent disk links for label and uuid depend on the
246 util-linux-ng version (2.15) of blkid now. Older versions of blkid
247 can not be used with udev.
249 Libudev allows to subscribe to udev events. To prevent unwanted messages
250 to be delivered, and waking up the subscribing process, a filter can be
251 installed, to drop messages inside a kernel socket filter. The filters
252 match on the <subsytem>:<devtype> properties of the device.
253 This is part of the ongoing effort to replace HAL, and switch current
254 users over to directly use libudev.
255 Libudev is still marked as experimental, and its interface might
256 eventually change if needed, but no major changes of the currently exported
257 interface are expected anymore, and a first stable release should happen
260 A too old kernel (2.6.21) or a kernel with CONFIG_SYSFS_DEPRECATED
261 is not supported since while and udevd will log an error message at
262 startup. It should still be able to boot-up, but advanced rules and system
263 services which depend on the information not available in the old sysfs
264 format will fail to work correctly.
266 DVB device naming is supplied by the kernel now. In case older kernels
267 need to be supported, the old shell script should be added to a compat
274 The processed udev events get send back to the netlink socket. Libudev
275 provides access to these events. This is work-in-progress, to replace
276 the DeviceKit daemon functionality directly with libudev. There are
277 upcoming kernel changes to allow non-root users to subcribe to these
284 "udevadm settle" now optionally accepts a range of events to wait for,
285 instead of waiting for "all" events.
291 The installed watch for block device metadata changes is now removed
292 during event hadling, because some (broken) tools may be called from udev
293 rules and (wrongly) open the device with write access. After the finished
294 event handling the watch is restored.
300 Device nodes can be watched for changes with inotify with OPTIONS="watch".
301 If closed after being opened for writing, a "change" uevent will occur.
302 /dev/disk/by-{label,uuid}/* symlinks will be automatically updated.
308 The udevadm test command has no longer a --force option, nodes and symlinks
309 are always updated with a test run now.
311 The udevd daemon can be started with --resolve-names=never to avoid all user
312 and group lookups (e.g. in cut-down systems) or --resolve-names=late to
313 lookup user and groups every time events are handled.
319 We are currently merging the Ubuntu rules in the udev default rules,
320 and get one step closer to provide a common Linux /dev setup, regarding
321 device names, symlinks, and default device permissions. On udev startup,
322 we now expect the following groups to be resolvable to their ids with
324 disk, cdrom, floppy, tape, audio, video, lp, tty, dialout, kmem.
325 LDAP setups need to make sure, that these groups are always resolvable at
326 bootup, with only the rootfs mounted, and without network access available.
328 Some systems may need to add some new, currently not used groups, or need
329 to add some users to new groups, but the cost of this change is minimal,
330 compared to the pain the current, rather random, differences between the
331 various distributions cause for upstream projects and third-party vendors.
333 In general, "normal" users who log into a machine should never be a member
334 of any such group, but the device-access should be managed by dynamic ACLs,
335 which get added and removed for the specific users on login/logout and
336 session activity/inactivity. These groups are only provided for custom setups,
337 and mainly system services, to allow proper privilege separation.
338 A video-streaming daemon uid would be a member of "audio" and "video", to get
339 access to the sound and video devices, but no "normal" user should ever belong
340 to the "audio" group, because he could listen to the built-in microphone with
341 any ssh-session established from the other side of the world.
343 /dev/serial/by-{id,path}/ now contains links for ttyUSB devices,
344 which do not depend on the kernel device name. As usual, unique
345 devices - only a single one per product connected, or a real
346 USB serial number in the device - are always found with the same
347 name in the by-id/ directory.
348 Completely identical devices may overwrite their names in by-id/
349 and can only be found reliably in the by-path/ directory. Devices
350 specified by by-path/ must not change their connection, like the
351 USB port number they are plugged in, to keep their name.
353 To support some advanced features, Linux 2.6.22 is the oldest supported
354 version now. The kernel config with enabled SYSFS_DEPRECATED is no longer
355 supported. Older kernels should still work, and devices nodes should be
356 reliably created, but some rules and libudev will not work correctly because
357 the old kernels do not provide the expected information or interfaces.
363 Fix for a possible segfault while swapping network interface names in udev
370 The group "video" is part of the default rules now.
374 Bugfix for kernels using SYSFS_DEPRECATED* option and finding parent
375 block devices in some cases. No common distro uses this option anymore,
376 and we do not get enough testing for this and recent udev versions. If
377 this option is not needed to run some old distro with a new kernel,
378 it should be disabled in the kernel config.
380 Bugfix for the $links substitution variable, which may crash if no links
381 are created. This should not happen in usual setups because we always
382 create /dev/{block,char}/ links.
384 The strings of the parsed rules, which are kept in memory, no longer
385 contain duplicate entries, or duplicate tails of strings. This, and the
386 new rules parsing/matching code reduces the total in-memory size of
387 a huge distro rule sets to 0.08 MB, compared to the 1.2MB of udev
390 The export of DEVTYPE=disk/partition got removed from the default
391 rules. This value is available from the kernel. The pnp shell script
392 modprobe hack is removed from the default rules. ACPI devices have _proper_
393 modalias support and take care of the same functionality.
394 Installations which support old kernels, but install current default
395 udev rules may want to add that to the compat rules file.
397 Libvolume_id now always probes for all known filesystems, and does not
398 stop at the first match. Some filesystems are marked as "exclusive probe",
399 and if any other filesytem type matches at the same time, libvolume_id
400 will, by default, not return any probing result. This is intended to prevent
401 mis-detection with conflicting left-over signatures found from earlier
402 file system formats. That way, we no longer depend on the probe-order
403 in case of multiple competing signatures. In some setups the kernel allows
404 to mount a volume with just the old filesystem signature still in place.
405 This may damage the new filesystem and cause data-loss, just by mounting
406 it. Because volume_id can not decide which one the correct signature is,
407 the wrong signatures need to be removed manually from the volume, or the
408 volume needs to be reformatted, to enable filesystem detection and possible
413 Fix segfault if compiled without optimization and dbg() does not get
414 compiled out and uses variables which are not available.
418 Bugfixes. (And maybe new bugs. :))
420 The rule matching engine got converted from a rule list to a token
421 array which reduced the in-memory rules representation of a full
422 featured distros with thousends of udev rules from 1.2MB to 0.12 MB.
423 Limits like 5 ENV and ATTR matches, and one single instance for most
424 other keys per rule are gone.
426 The NAME assignment is no longer special cased. If later rules assign
427 a NAME value again, the former value will be overwritten. As usual
428 for most other keys, the NAME value can be protected by doing a final
429 assignment with NAME:="<value>".
431 All udev code now uses libudev, which is also exported. The library
432 is still under development, marked as experimental, and its interface
433 may change as long as the DeviceKit integration is not finished.
435 Many thanks to Alan Jenkins for his continuous help, and finding and
436 optimizing some of the computing expensive parts.
442 Kernel devices and device nodes are connected now by reverse indizes in
443 /sys and /dev. A device number retrieved by a stat() or similar, the
444 kernel device directory can be found by looking up:
445 /sys/dev/{block,char}/<maj>:<min>
446 and the device node of the same device by looking up:
447 /dev/{block,char}/<maj>:<min>
451 Fix recently introduced bug, which caused a compilation without large
452 file support, where vol_id does not recognize raid signatures at the end
455 Firewire disks now create both, by-id/scsi-* and by-id/ieee-* links.
456 Seems some kernel versions prevent the creation of the ieee-* links,
457 so people used the scsi-* link which disappeared now.
459 More libudev work. Almost all udevadm functionality comes from libudev
462 udevadm trigger has a new option --type, which allows to trigger events
463 for "devices", for "subsystems", or "failed" devices. The old option
464 --retry-failed" still works, but is no longer mentioned in the man page.
470 The udevadm info --device-id-of-file= output has changed to use
471 the obvious format. Possible current users should use the --export
472 option which is not affected.
474 The old udev commands symlinks to udevadm are not installed, if
475 these symlinks are used, a warning is printed.
481 Optical drive's media is no longer probed for raid signatures,
482 reading the end of the device causes some devices to malfunction.
483 Also the offset of the last session found is used now to probe
486 The volume_id library got a major version number update to 1,
487 some deprecated functions are removed.
489 A shared library "libudev" gets installed now to provide access
490 to udev device information. DeviceKit, the successor of HAL, will
491 need this library to access the udev database and search sysfs for
493 The library is currently in an experimental state, also the API is
494 expected to change, as long as the DeviceKit integration is not
499 We use ./configure now. See INSTALL for details. Current
502 "/usr" - prefix for man pages, include files
504 "" - the root filesystem, prefix for libs and binaries
508 "lib" - directory name for libraries, not a path name
509 multilib 64bit systems may use "lib64" instead of "lib"
511 compile-in verbose debug messages
513 disable all logging and compile-out all log strings
515 link against SELInux libraries, to set the expected context
518 In the default rules, the group "disk" gets permissions 0660 instead
519 of 0640. One small step closer to unify distro rules. Some day, all
520 distros hopefully end up with the same set of rules.
522 No symlinks to udevadm are installed anymore, if they are still needed,
523 they should be provided by the package.
529 Default udev rules, which are not supposed to be edited by the user, should
530 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
531 the udev package and will be replaced with an update. Udev will pick up rule
533 /lib/udev/rules.d/ - default installed rules
534 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
535 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
536 It does not matter in which directory a rule file lives, all files are sorted
539 To help creating /dev/root, we have now:
540 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
543 In case the current --device-id-of-file is already used, please switch to
544 the --export format version, it saves the output parsing and the old
545 format will be changed to use ':' as a separator, like the format in the
550 Fix cdrom_id to properly recognize blank media.
556 Tape drive id-data is queried from /dev/bsg/* instead of the tape
557 nodes. This avoids rewinding tapes on open().
563 The symlinks udevcontrol and udevtrigger are no longer installed by
566 The scsi_id program does not depend on sysfs anymore. It can speak
567 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
568 data, which should solve some old problems with tape devices, where
569 we better do not open all tape device nodes to identify the device.
575 The cdrom_id program is replaced by an advanced version, which can
576 detect most common device types, and also properties of the inserted
577 media. This is part of moving some basic functionality from HAL into
578 udev (and the kernel).
584 The last WAIT_FOR_SYSFS rule is removed from the default rules.
586 The symlinks to udevadm for the debugging tools: udevmonitor and
587 udevtest are no longer created.
589 The symlinks to the udevadm man page for the old tool names are
592 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
593 should be prefixed with '@' to indicate that the path is not a
604 Udevstart is removed from the tree, it did not get installed for
605 a long time now, and is long replaced by trigger and settle.
611 All udev tools are merged into a single binary called udevadm.
612 The old names of the tools are built-in commands in udevadm now.
613 Symlinks to udevadm, with the names of the old tools, provide
614 the same functionality as the standalone tools. There is also
615 only a single udevadm.8 man page left for all tools.
617 Tools like mkinitramfs should be checked, if they need to include
618 udevadm in the list of files.
628 The etc/udev/rules.d/ directory now contains a default set of basic
629 udev rules. This initial version is the result of a rules file merge
630 of Fedora and openSUSE. For these both distros only a few specific
631 rules are left in their own file, named after the distro. Rules which
632 are optionally installed, because they are only valid for a specific
633 architecture, or rules for subsystems which are not always used are
634 in etc/udev/packages/.
640 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
641 actions by dynamically created rules.
643 SYMLINK=="<value>" matches agains the entries in the list of
644 currently defined symlinks. The links are not created in the
645 filesystem at that point in time, but the values can be matched.
647 RUN{ignore_error}+="<program>" will ignore any exit code from the
648 program and not record as a failed event.
654 Final merge of patches/features from the Ubuntu package.
660 Control characters in filesystem label strings are no longer silenty
661 removed, but hex-encoded, to be able to uniquely identify the device
662 by its symlink in /dev/disk/by-label/.
663 If libvolume_id is used by mount(8), LABEL= will work as expected,
664 if slashes or other characters are used in the label string.
666 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
667 can be specified now. The TEST key accepts an optional mode mask
668 TEST{0100}=="<is executable file>".
670 Scsi_id now supports a mode without expecting scsi-specific sysfs
671 entries to allow the extraction of cciss-device persistent properties.
677 In the future, we may see uuid's which are just simple character
678 strings (see the DDF Raid Specification). For that reason vol_id now
679 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
680 the creation of symlinks, the *_SAFE values ensure, that no control
681 or whitespace characters are used in the filename.
683 Possible users of libvolume_id, please use the volume_id_get_* functions.
684 The public struct will go away in a future release of the library.
690 Removal of useless extras/eventrecorder.sh.
700 The directory multiplexer for dev.d/ and hotplug.d are finally removed
701 from the udev package.
707 Symlinks can have priorities now, the priority is assigned to the device
708 and specified with OPTIONS="link_priority=100". Devices with higher
709 priorities overwrite the symlinks of devices with lower priorities.
710 If the device that currently owns the link, goes away, the symlink
711 will be removed, and recreated, pointing to the next device with the
712 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
713 more reliable, if multiple devices contain the same metadata and overwrite
716 The dasd_id program is removed from the udev tree, and dasdinfo, with the
717 needed rules, are part of the s390-tools now.
719 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
720 we may get the scsi sysfs mess fixed some day, and this will only catch
721 the devices we are looking for.
723 USB serial numbers for storage devices have the target:lun now appended,
724 to make it possibble to distinguish broken multi-lun devices with all
725 the same SCSI identifiers.
727 Note: The extra "run_directory" which searches and executes stuff in
728 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
729 with the next release. Make sure, that you don't use it anymore, or
730 provides your own implementation of that inefficient stuff.
731 We are tired of reports about a "slow udev", because these directories
732 contain stuff, that runs with _every_ event, instead of using rules,
733 that run programs only for the matching events.
743 DRIVER== will match only for devices that actually have a real
744 driver. DRIVERS== must be used, if parent devices should be
745 included in the match.
747 Libvolume_id's "linux_raid" detection needed another fix.
755 Add additional check to volume_id detection of via_raid, cause
756 some company decided to put a matching pattern all over the empty
757 storage area of their music players.
761 Fix path_id for SAS devices.
765 The udev daemon can be started with --debug-trace now, which will
766 execute all events serialized to get a chance to catch a possible
767 action that crashes the box.
769 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
770 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
771 are excluded from the warning. Referencing parent attributes directly
772 may break when something in the kernel driver model changes. Udev will
773 just find the attribute by walking up the parent chain.
775 Udevtrigger now sorts the list of devices depending on the device
776 dependency, so a "usb" device is triggered after the parent "pci"
781 Revert persistent-storage ata-serial '_' '-' replacement.
787 Udevtrigger can now filter the list of devices to be triggered. Matches
788 for subsystems or sysfs attributes can be specified.
790 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
791 zero-sized files to avoid pointing to /sys and confuse broken tools which
792 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
795 The rules and scripts to create udev rules for persistent network
796 devices and optical drives are in the extras/rules_generator directory
797 now. If you use something similar, please consider replacing your own
798 version with this, to share the support effort. The rule_generator
799 installs its own rules into /etc/udev/rules.d.
801 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
802 the rule_generator depends on cdrom_id to be called in an earlier rule.
808 Renaming of some key names (the old names still work):
809 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
810 (The behavior of the key DRIVER will change soon in one of the next
811 releases, to match only the event device, please switch to DRIVERS
812 instead. If DRIVER is used, it will behave like DRIVERS, but an error
814 With the new key names, we have a more consistent and simpler scheme.
815 We can match the properties of the event device only, with: KERNEL,
816 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
817 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
818 longer mentioned in the man page and should be switched in the rule
821 ATTR{file}="value" can be used now, to write to a sysfs file of the
822 event device. Instead of:
823 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
825 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
827 All the PHYSDEV* keys are deprecated and will be removed from a
829 PHYDEVPATH - is the path of a parent device and should not be
831 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
832 matched with SUBSYSTEMS==
833 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
834 Newer kernels will have DRIVER in the environment,
835 for older kernels udev puts in. Class device will
836 no longer carry this property of a parent and
837 DRIVERS== can be used to match such a parent value.
838 Note that ENV{DRIVER} is only available for a few bus devices, where
839 the driver is already bound at device event time. On coldplug, the
840 events for a lot devices are already bound to a driver, and they will have
841 that value set. But on hotplug, at the time the kernel creates the device,
842 it can't know what driver may claim the device after that, therefore
843 in most cases it will be empty.
845 Failed events should now be re-triggered with:
846 udevtrigger --retry-failed.
847 Please switch to this command, so we keep the details of the /dev/.udev/failed/
848 files private to the udev tools. We may need to switch the current symlink
849 target, cause some obviously broken tools try to scan all files in /dev
850 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
851 million times. This takes ages on slow boxes.
853 The udevinfo attribute walk (-a) now works with giving a device node
854 name (-n) instead of a devpath (-p). The query now always works, also when
855 no database file was created by udev.
857 The built-in /etc/passwd /etc/group parser is removed, we always depend on
858 getpwnam() and getgrnam() now. One of the next releases will depend on
859 fnmatch() and may use getopt_long().
863 Bugfixes and small improvements.
867 Fix path_id for recent kernels.
873 Added support for swapping network interface names, by temporarily
874 renaming the device and wait for the target name to become free.
878 The built-in MODALIAS key and substitution is removed.
882 The binary firmware helper is replaced by the usual simple
883 shell script. Udevsend is removed from the tree.
891 Some more keys require the correct use of '==' and '=' depending
892 on the kind of operation beeing an assignment or a match. Rules
893 with invalid operations are skipped and logged to syslog. Please
894 test with udevtest if the parsing of your rules throws errors and
895 fix possibly broken rules.
899 Provide "udevsettle" to wait for all current udev events to finish.
900 It also watches the current kernel netlink queue by comparing the
901 even sequence number to make sure that there are no current pending
902 events that have not already arrived in the daemon.
906 Fix rule to skip persistent rules for removable IDE devices, which
907 also skipped optical IDE drives.
909 All *_id program are installed in /lib/udev/ by default now.
911 No binary is stripped anymore as this should be done in the
912 packaging process and not at build time.
914 libvolume_id is provided as a shared library now and vol_id is
915 linked against it. Also one of the next HAL versions will require
916 this library, and the HAL build process will also require the
917 header file to be installed. The copy of the same code in HAL will
918 be removed to have only a single copy left on the system.
922 Add persistent links for SCSI tapes. The rules file is renamed
923 to 60-persistent-storage.rules.
925 Create persistent path for usb devices. Can be used for all sorts
926 of devices that can't be distinguished by other properties like
927 multiple identical keyboards and mice connected to the same box.
929 Provide "udevtrigger" program to request events on coldplug. The
930 shell script is much too slow with thousends of devices.
934 Fix persistent disk rules to exclude removable IDE drives.
936 Warn if %e, $modalias or MODALIAS is used.
940 Fix queue export, which wasn't correct for subsequent add/remove
941 events for the same device.
945 Fix cramfs detection on big endian.
947 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
952 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
953 attributes were only checked at the parent device that matched the
954 by BUS requested subsystem. Fix it to also look at the device we
955 received the event for.
957 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
962 Fix a bug where NAME="" would prevent RUN from beeing executed.
964 RUN="/bin/program" does not longer automatically add the subsystem
965 as the first parameter. This is from the days of /sbin/hotplug
966 which is dead now and it's just confusing to need to add a space at
967 the end of the program name to prevent this.
968 If you use rules that need the subsystem as the first parameter,
969 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
970 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
974 The udev man page has moved to udev(7) as it does not describe a command
975 anymore. The programs udev, udevstart and udevsend are no longer installed
976 by default and must be copied manually, if they should be installed or
977 included in a package.
979 Fix a bug where "ignore_device" could run earlier collected RUN keys before
980 the ignore rule was applied.
982 More preparation for future sysfs changes. usb_id and scsi_id no longer
983 depend on a magic order of devices in the /devices chain. Specific devices
984 should be requested by their subsytem.
986 This will always find the scsi parent device without depending on a specific
988 dev = sysfs_device_get(devpath);
989 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
991 The "device" link in the current sysfs layout will be automatically
992 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
993 parent in the devpath. If a device is requested by it's symlink, like all
994 class devices in the new sysfs layout will look like, it gets automatically
995 resolved and substituted with the real devpath and not the symlink path.
998 A similar logic must be applied to _all_ sysfs users, including
999 scripts, that search along parent devices in sysfs. The explicit use of
1000 the "device" link must be avoided. With the future sysfs layout all
1001 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
1002 back to the "class" or the "bus". The layout of the parent devices in
1003 /devices is not necessarily expected to be stable across kernel releases and
1004 searching for parents by their subsystem should make sysfs users tolerant
1005 for changed parent chains.
1009 Prepare udev to work with the experimental kernel patch, that moves
1010 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
1012 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
1013 moving the class devices to /sys/devices.
1015 Thanks again to Marco for help finding a hopefully nice compromise
1016 to make %b simpler and working again.
1020 Complete removal of libsysfs, replaced by simple helper functions
1021 which are much simpler and a bit faster. The udev daemon operatesentirely
1022 on event parameters and does not use sysfs for simple rules anymore.
1023 Please report any new bugs/problems, that may be caused by this big
1024 change. They will be fixed immediately.
1026 The enumeration format character '%e' is deprecated and will be
1027 removed sometimes from a future udev version. It never worked correctly
1028 outside of udevstart, so we can't use it with the new parallel
1029 coldplug. A simple enumeration is as useless as the devfs naming
1030 scheme, just get rid of both if you still use it.
1032 MODALIAS and $modalias is not needed and will be removed from one of
1033 the next udev versions, replace it in all rules with ENV{MODALIAS} or
1034 the sysfs "modalias" value.
1036 Thanks a lot to Marco for all his help on finding and fixing bugs.
1040 Let scsi_id request libata drive serial numbers from page 0x80.
1042 Renamed etc/udev/persistent.rules to persistent-disk.rules and
1043 added /dev/disk/by-name/* for device mapper device names.
1045 Removed %e from the man page. It never worked reliably outside
1046 of udevstart and udevstart is no longer recommended to use.
1050 Symlinks are now exported to the event environment. Hopefully it's no
1051 longer needed to run udevinfo from an event process, like it was
1052 mentioned on the hotplug list:
1053 UDEV [1134776873.702967] add@/block/sdb
1056 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
1060 Fix a problem if udevsend is used as the hotplug handler and tries to use
1061 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
1062 and this kind of problems will hopefully go away soon.
1066 All built-in logic to work around bad sysfs timing is removed with this
1067 version. The need to wait for sysfs files is almost fixed with a kernel
1068 version that doesn't work with this udev version anyway. Until we fix
1069 the timing of the "bus" link creation, the former integrated logic should
1070 be emulated by a rule placed before all other rules:
1071 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
1073 The option "udev_db" does no longer exist. All udev state will be in
1074 /$udev_root/.udev/ now, there is no longer an option to set this
1076 If the init script or something else used this value, just depend on
1077 this hardcoded path. But remember _all_content_ of this directory is
1078 still private to udev and can change at any time.
1080 Default location for rule sripts and helper programs is now: /lib/udev/.
1081 Everything that is not useful on the commandline should go into this
1082 directory. Some of the helpers in the extras folder are installed there
1083 now. The rules need to be changed, to find the helpers there.
1085 Also /lib/udev/devices is recommended as a directory where packages or
1086 the user can place real device nodes, which get copied over to /dev at
1087 every boot. This should replace the various solutions with custom config
1090 Udevsend does no longer start the udev daemon. This must be done with
1091 the init script that prepares /dev on tmpfs and creates the initial nodes,
1092 before starting the daemon.
1096 Silent a too verbose error logging for the old hotplug.d/ dev.d/
1099 The copy of klibc is removed. A systemwide installed version of klibc
1100 should be used to build a klibc udev now.
1104 NAME="" will not create any nodes, but execute RUN keys. To completely
1105 ignore an event the OPTION "ignore_device" should be used.
1107 After removal of the reorder queue, events with a TIMEOUT can be executed
1108 without any queuing now.
1112 Fixed bug in udevd, if inotify is not available. We depend on netlink
1113 uevents now, kernels without that event source will not work with that
1114 version of udev anymore.
1118 The rule parsing happens now in the daemon once at startup, all udev
1119 event processes inherit the already parsed rules from the daemon.
1120 It is shipped with SUSE10.0 and reduces heavily the system load at
1121 startup. The option to save precompiled rules and let the udev process
1122 pick the them up is removed, as it's no longer needed.
1124 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
1125 device. Libsysfs is changed to "translate" the requested link into the
1126 real device path, as it would happen with the hotplug event. Otherwise
1127 device removal and the udev database will not work.
1129 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
1132 A few improvements for vol_id, the filesytem probing code.
1136 Fix a stupid typo in extras/run_directory for "make install".
1138 scsi_id creates the temporary devnode now in /dev for usage with a
1139 non-writable /tmp directory.
1141 The uevent kernel socket buffer can carry app. 50.000 events now,
1142 let's see who can break this again. :)
1144 The upcoming kernel will have a new input driver core integration.
1145 Some class devices are now symlinks to the real device. libsysfs
1146 needs a fix for this to work correctly. Udevstart of older udev
1147 versions will _not_ create these devices!
1151 Fix a 'install' target in the Makefile, that prevents EXTRAS from
1156 A bunch of mostly trivial bugfixes. From now on no node name or
1157 symlink name can contain any character than plain whitelisted ascii
1158 characters or validated utf8 byte-streams. This is needed for the
1159 /dev/disk/by-label/* links, because we import untrusted data and
1160 export it to the filesystem.
1164 More bugfixes. If udevd was started from the kernel, we don't
1165 have stdin/stdout/stderr, which broke the forked tools in some
1170 Bugfix. udevstart event ordering was broken for a long time.
1171 The new run_program() uncovered it, because /dev/null was not
1172 available while we try to run external programs.
1173 Now udevstart should create it before we run anything.
1177 Minor bugfixes and some distro rules updates. If you don't have the
1178 persistent disk rules in /dev/disk/by-*/* on your distro, just
1179 grab it from here. :)
1183 We can use socket communication now to pass events from udev to
1185 RUN+="socket:/org/freedesktop/hal/udev_event"
1186 will pass the whole udev event to the HAL daemon without the need
1187 for a forked helper. (See ChangeLog for udevmonitor, as an example)
1191 Mostly bugfixes and see ChangeLog.
1193 The test for the existence of an environment value should be
1195 ENV{KEY}=="*" to ENV{KEY}=="?*"
1196 because "*" will not fail anymore, if the key does not exist or
1201 Bugfixes and a few tweaks described in the ChangeLog.
1205 Mostly a Bugfix release.
1207 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
1208 timing with custom rules.
1212 We changed the internal rule storage format. Our large rule files took
1213 2 MB of RAM, with the change we are down to 99kB.
1215 If the device-node has been created with default name and no symlink or
1216 options are to remenber, it is not longer stored in the udevdb. HAL will
1217 need to be updated to work correctly with that change.
1219 To overrride optimization flags, OPTFLAGS may be used now.
1227 Major changes happened with this release. The goal is to take over the
1228 complete kernel-event handling and provide a more efficient way to dispatch
1229 kernel events. Replacing most of the current shell script logic and the
1230 kernel forked helper with a netlink-daemon and a rule-based event handling.
1232 o udevd listens to netlink events now. The first valid netlink event
1233 will make udevd ignore any message from udevsend that contains a
1234 SEQNUM, to avoid duplicate events. The forked events can be disabled
1236 echo "" > /proc/sys/kernel/hotplug
1237 For full support, the broken input-subsytem needs to be fixed, not to
1238 bypass the driver core.
1240 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
1241 removed from udev itself and must be emulated by calling small
1242 helper binaries provided in the extras folder:
1243 make EXTRAS=extras/run_directory/
1244 will build udev_run_devd and udev_run_hotplugd, which can be called
1245 from a rule if needed:
1246 RUN+="/sbin/udev_run_hotplugd"
1247 The recommended way to handle this is to convert all the calls from
1248 the directories to explicit udev rules and get completely rid of the
1249 multiplexing. (To catch a ttyUSB event, you now no longer need to
1250 fork and exit 300 tty script instances you are not interested in, it
1251 is just one rule that matches exactly the device.)
1253 o udev handles now _all_ events not just events for class and block
1254 devices, this way it is possible to control the complete event
1255 behavior with udev rules. Especially useful for rules like:
1256 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
1258 o As used in the modalias rule, udev supports now textual
1259 substitution placeholder along with the usual format chars. This
1260 needs to be documented, for now it's only visible in udev_rules_parse.c.
1262 o The rule keys support now more operations. This is documented in the
1263 man page. It is possible to add values to list-keys like the SYMLINK
1264 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
1265 Also "final"-assignments are supported by using KEY:="value", which will
1266 prevent changing the key by any later rule.
1268 o kernel 2.6.12 has the "detached_state" attribute removed from
1269 sysfs, which was used to recognize sysfs population. We switched that
1270 to wait for the "bus" link, which is only available in kernels after 2.6.11.
1271 Running this udev version on older kernels may cause a short delay for
1274 o To provide infrastructure for persistent device naming, the id programs:
1275 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
1276 to export the probed data in environment key format:
1277 pim:~ # /sbin/ata_id --export /dev/hda
1278 ID_MODEL=HTS726060M9AT00
1279 ID_SERIAL=MRH401M4G6UM9B
1280 ID_REVISION=MH4OA6BA
1282 The following rules:
1283 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
1284 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
1287 kay@pim:~> tree /dev/disk
1290 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
1291 | `-- IBM-Memory_Key -> ../../sda
1293 | |-- swap -> ../../hda1
1294 | |-- date -> ../../sda1
1295 | `-- home -> ../../hda3
1297 |-- 2E08712B0870F2E7 -> ../../hda3
1298 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
1299 |-- E845-7A89 -> ../../sda1
1300 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
1302 The IMPORT= operation will import these keys in the environment and make
1303 it available for later PROGRAM= and RUN= executed programs. The keys are
1304 also stored in the udevdb and can be queried from there with one of the
1307 o A few binaries are silently added to the repository, which can be used
1308 to replay kernel events from initramfs instead of using coldplug. udevd
1309 can be instructed now to queue-up events while the stored events from
1310 initramfs are filled into the udevd-queue. This code is still under
1311 development and there is no documentation now besides the code itself.
1312 The additional binaries get compiled, but are not installed by default.
1314 o There is also a temporary fix for a performance problem where too many
1315 events happen in parallel and every event needs to parse the rules.
1316 udev can now read precompiled rules stored on disk. This is likely to be
1317 replaced by a more elegant solution in a future udev version.
1321 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
1322 Fix for libsysfs not to expect this file was added.
1326 All rules are applied now, but only the first matching rule with a NAME-key
1327 will be applied. All later rules with NAME-key are completely ignored. This
1328 way system supplied symlinks or permissions gets applied to user-defined
1332 Please check your rules setup, if you may need to add OPTIONS="last_rule"
1333 to some rules, to keep the old behavior.
1335 The rules are read on "remove"-events too. That makes is possible to match
1336 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
1337 instruct udev to ignore an event (OPTIONS="ignore_device").
1338 The new ACTION-key may be used to let a rule act only at a "remove"-event.
1340 The new RUN-key supports rule-based execution of programs after device-node
1341 handling. This is meant as a general replacement for the dev.d/-directories
1342 to give fine grained control over the execution of programs.
1344 The %s{}-sysfs format char replacement values are searched at any of the
1345 devices in the device chain now, not only at the class-device.
1347 We support log priority levels now. The value udev_log in udev.conf is used
1348 to determine what is printed to syslog. This makes it possible to
1349 run a version with compiled-in debug messages in a production environment
1350 which is sometimes needed to find a bug.
1351 It is still possible to supress the inclusion of _any_ syslog usage with
1352 USE_LOG=false to create the smallest possible binaries if needed.
1353 The configured udev_log value can be overridden with the environment variable
1358 Possible use of a system-wide klibc:
1359 make USE_KLIBC=true KLCC=/usr/bin/klcc all
1360 will link against an external klibc and our own version will be ignored.
1364 We support an unlimited count of symlinks now.
1366 If USE_STATIC=true is passed to a glibc build, we link statically and use
1367 a built-in userdb parser to resolve user and group names.
1369 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
1370 we walk up the chain of physical devices to find a match.
1372 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
1373 easy to skip certain attribute matches without composing rules with weird
1374 character class negations like:
1375 KERNEL="[!s][!c][!d]*"
1376 this can now be replaced with:
1378 The current simple '=' is still supported, and should work as it does today,
1379 but existing rules should be converted if possible, to be better readable.
1381 We have new ENV{}== key now, to match against a maximum of 5 environment
1384 udevstart is its own binary again, because we don't need co carry this araound
1385 with every forked event.