5 All distribution specific rules are removed from the udev source tree,
6 most of them are no longer needed. The Gentoo rules which allow to support
7 older kernel versions, which are not covered by the default rules anymore
8 has moved to rules/misc/30-kernel-compat.rules.
14 The option --debug-trace and the environemnt variable UDEVD_MAX_CHILDS=
15 was removed from udevd.
17 Udevd now checks the kernel commandline for the following variables:
18 udev.log-priority=<syslog priority>
19 udev.children-max=<maximum number of workers>
20 udev.exec-delay=<seconds to delay the execution of RUN=>
21 to help debuging coldplug setups where the loading of a kernel
22 module crashes the system.
24 The subdirectory in the source tree rules/packages has been renamed to
25 rules/arch, anc contains only architecture specific rules now.
35 Now the udev daemon itself, does on startup:
36 - copy the content of /lib/udev/devices to /dev
37 - create the standard symlinks like /dev/std{in,out,err},
38 /dev/core, /dev/fd, ...
39 - use static node information provided by kernel modules
40 and creates these nodes to allow module on-demand loading
41 - possibly apply permissions to all ststic nodes from udev
42 rules which are annotated to match a static node
44 The default mode for a device node is 0600 now to match the kernel
45 created devtmpfs defaults. If GROUP= is specified and no MODE= is
46 given the default will be 0660.
52 Udev now gradually starts to pass control over the primary device nodes
53 and their names to the kernel, and will in the end only manage the
54 permissions of the node, and possibly create additional symlinks.
55 As a first step NAME="" will be ignored, and NAME= setings with names
56 other than the kernel provided name will result in a logged warning.
57 Kernels that don't provide device names, or devtmpfs is not used, will
58 still work as they did before, but it is strongly recommended to use
59 only the same names for the primary device node as the recent kernel
60 provides for all devices.
64 Fix broken firmware loader search path.
70 "udevadm trigger" defaults to "change" events now instead of "add"
71 events. The "udev boot script" might need to add "--action=add" to
72 the trigger command if not already there, in case the initial coldplug
73 events are expected as "add" events.
75 The option "all_partitons" was removed from udev. This should not be
76 needed for usual hardware. Udev can not safely make assumptions
77 about non-existing partition major/minor numbers, and therefore no
78 longer provide this unreliable and unsafe option.
80 The option "ignore_remove" was removed from udev. With devtmpfs
81 udev passed control over device nodes to the kernel. This option
82 should not be needed, or can not work as advertised. Neither
83 udev nor the kernel will remove device nodes which are copied from
84 the /lib/udev/devices/ directory.
86 All "add|change" matches are replaced by "!remove" in the rules and
87 in the udev logic. All types of events will update possible symlinks
88 and permissions, only "remove" is handled special now.
90 The modem modeswitch extra was removed and the external usb_modeswitch
91 program should be used instead.
93 New and fixed keymaps.
103 Kernels with SYSFS_DEPRECATED=y are not supported since a while. Many users
104 depend on the current sysfs layout and the information not available in the
105 deprecated layout. All remaining support for the deprecated sysfs layout is
110 Fix for a possible endless loop in the new input_id program.
116 The option "ignore_device" does no longer exist. There is no way to
117 ignore an event, as libudev events can not be suppressed by rules.
118 It only prevented RUN keys from being executed, which results in an
119 inconsistent behavior in current setups.
121 BUS=, SYSFS{}=, ID= are long deprecated and should be SUBSYSTEM(S)=,
122 ATTR(S){}=, KERNEL(S)=. It will cause a warning once for every rule
125 The support for the deprecated IDE devices has been removed from the
126 default set of rules. Distros who still care about non-libata drivers
127 need to add the rules to the compat rules file.
129 The ID_CLASS property on input devices has been replaced by the more accurate
130 set of flags ID_INPUT_{KEYBOARD,KEY,MOUSE,TOUCHPAD,TABLET,JOYSTICK}. These are
131 determined by the new "input_id" prober now. Some devices, such as touchpads,
132 can have several classes. So if you previously had custom udev rules which e. g.
133 checked for ENV{ID_CLASS}=="kbd", you need to replace this with
134 ENV{ID_INPUT_KEYBOARD}=="?*".
140 To support DEVPATH strings larger than the maximum file name length, the
141 private udev database format has changed. If some software still reads the
142 private files in /dev/.udev/, which it shouldn't, now it's time to fix it.
143 Please do not port anything to the new format again, everything in /dev/.udev
144 is and always was private to udev, and may and will change any time without
147 Multiple devices claiming the same names in /dev are limited to symlinks
148 only now. Mixing identical symlink names and node names is not supported.
149 This reduces the amount of data in the database significantly.
151 NAME="%k" causes a warning now. It's is and always was completely superfluous.
152 It will break kernel supplied DEVNAMEs and therefore it needs to be removed
155 Most NAME= instructions got removed. Kernel 2.6.31 supplies the needed names
156 if they are not the default. To support older kernels, the NAME= rules need to
157 be added to the compat rules file.
159 Symlinks to udevadm with the old command names are no longer resolved to
160 the udevadm commands.
162 The udev-acl tool got adopted to changes in ConsoleKit. Version 0.4.1 is
165 The option "last_rule" does no longer exist. Its use breaks too many
166 things which expect to be run from independent later rules, and is an idication
167 that something needs to be fixed properly instead.
169 The gudev API is no longer marked as experimental,
170 G_UDEV_API_IS_SUBJECT_TO_CHANGE is no longer needed. The gudev introspection
171 is enabled by default now. Various projects already depend on introspection
172 information to bind dynamic languages to the gudev interfaces.
178 The udevadm trigger "--retry-failed" option, which is replaced since quite
179 a while by "--type=failed" is removed.
181 The failed tracking was not working at all for a few releases. The RUN
182 option "ignore_error" is replaced by a "fail_event_on_error" option, and the
183 default is not to track any failing RUN executions.
185 New keymaps, new modem, hid2hci updated.
189 Fix possible crash in udevd when worker processes are busy, rules are
190 changed at the same time, and workers get killed to reload the rules.
196 Properties set with ENV{.FOO}="bar" are marked private by starting the
197 name with a '.'. They will not be stored in the database, and not be
198 exported with the event.
200 Firmware files are looked up in:
201 /lib/firmware/updates/$(uname -r)
202 /lib/firmware/updates
203 /lib/firmware/$(uname -r)
207 ATA devices switched the property from ID_BUS=scsi to ID_BUS=ata.
208 ata_id, instead of scsi_id, is the default tool now for ATA devices.
214 The configure options have changed because another library needs to be
215 installed in a different location. Instead of exec_prefix and udev_prefix,
216 libdir, rootlibdir and libexecdir are used. The Details are explained in
219 Event processes now get re-used after they handled an event. This reduces
220 the number of forks and the pressure on the CPU significantly, because
221 cloned event processes no longer cause page faults in the main daemon.
222 After the events have settled, a few worker processes stay around for
223 future events, all others get cleaned up.
225 To be able to use signalfd(), udev depends on kernel version 2.6.25 now.
226 Also inotify support is mandatory now to run udev.
228 The format of the queue exported by the udev damon has changed. There is
229 no longer a /dev/.udev/queue/ directory. The current event queue can be
230 accessed with udevadm settle and libudedv.
232 Libudev does not have the unstable API header anymore. From now on,
233 incompatible changes will be handled by bumping the library major version.
235 To build udev from the git tree gtk-doc is needed now. The tarballs will
236 build without it and contain the pre-built documentation. An online copy
238 http://www.kernel.org/pub/linux/utils/kernel/hotplug/libudev/
240 The tools from the udev-extras repository have been merged into the main
241 udev repository. Some of the extras have larger external dependencies, and
242 they can be disabled with the configure switch --disable-extras.
248 The program vol_id and the library libvolume_id are removed from the
249 repository. Libvolume_id is merged with libblkid from the util-linux-ng
250 package. Persistent disk links for label and uuid depend on the
251 util-linux-ng version (2.15) of blkid now. Older versions of blkid
252 can not be used with udev.
254 Libudev allows to subscribe to udev events. To prevent unwanted messages
255 to be delivered, and waking up the subscribing process, a filter can be
256 installed, to drop messages inside a kernel socket filter. The filters
257 match on the <subsytem>:<devtype> properties of the device.
258 This is part of the ongoing effort to replace HAL, and switch current
259 users over to directly use libudev.
260 Libudev is still marked as experimental, and its interface might
261 eventually change if needed, but no major changes of the currently exported
262 interface are expected anymore, and a first stable release should happen
265 A too old kernel (2.6.21) or a kernel with CONFIG_SYSFS_DEPRECATED
266 is not supported since while and udevd will log an error message at
267 startup. It should still be able to boot-up, but advanced rules and system
268 services which depend on the information not available in the old sysfs
269 format will fail to work correctly.
271 DVB device naming is supplied by the kernel now. In case older kernels
272 need to be supported, the old shell script should be added to a compat
279 The processed udev events get send back to the netlink socket. Libudev
280 provides access to these events. This is work-in-progress, to replace
281 the DeviceKit daemon functionality directly with libudev. There are
282 upcoming kernel changes to allow non-root users to subcribe to these
289 "udevadm settle" now optionally accepts a range of events to wait for,
290 instead of waiting for "all" events.
296 The installed watch for block device metadata changes is now removed
297 during event hadling, because some (broken) tools may be called from udev
298 rules and (wrongly) open the device with write access. After the finished
299 event handling the watch is restored.
305 Device nodes can be watched for changes with inotify with OPTIONS="watch".
306 If closed after being opened for writing, a "change" uevent will occur.
307 /dev/disk/by-{label,uuid}/* symlinks will be automatically updated.
313 The udevadm test command has no longer a --force option, nodes and symlinks
314 are always updated with a test run now.
316 The udevd daemon can be started with --resolve-names=never to avoid all user
317 and group lookups (e.g. in cut-down systems) or --resolve-names=late to
318 lookup user and groups every time events are handled.
324 We are currently merging the Ubuntu rules in the udev default rules,
325 and get one step closer to provide a common Linux /dev setup, regarding
326 device names, symlinks, and default device permissions. On udev startup,
327 we now expect the following groups to be resolvable to their ids with
329 disk, cdrom, floppy, tape, audio, video, lp, tty, dialout, kmem.
330 LDAP setups need to make sure, that these groups are always resolvable at
331 bootup, with only the rootfs mounted, and without network access available.
333 Some systems may need to add some new, currently not used groups, or need
334 to add some users to new groups, but the cost of this change is minimal,
335 compared to the pain the current, rather random, differences between the
336 various distributions cause for upstream projects and third-party vendors.
338 In general, "normal" users who log into a machine should never be a member
339 of any such group, but the device-access should be managed by dynamic ACLs,
340 which get added and removed for the specific users on login/logout and
341 session activity/inactivity. These groups are only provided for custom setups,
342 and mainly system services, to allow proper privilege separation.
343 A video-streaming daemon uid would be a member of "audio" and "video", to get
344 access to the sound and video devices, but no "normal" user should ever belong
345 to the "audio" group, because he could listen to the built-in microphone with
346 any ssh-session established from the other side of the world.
348 /dev/serial/by-{id,path}/ now contains links for ttyUSB devices,
349 which do not depend on the kernel device name. As usual, unique
350 devices - only a single one per product connected, or a real
351 USB serial number in the device - are always found with the same
352 name in the by-id/ directory.
353 Completely identical devices may overwrite their names in by-id/
354 and can only be found reliably in the by-path/ directory. Devices
355 specified by by-path/ must not change their connection, like the
356 USB port number they are plugged in, to keep their name.
358 To support some advanced features, Linux 2.6.22 is the oldest supported
359 version now. The kernel config with enabled SYSFS_DEPRECATED is no longer
360 supported. Older kernels should still work, and devices nodes should be
361 reliably created, but some rules and libudev will not work correctly because
362 the old kernels do not provide the expected information or interfaces.
368 Fix for a possible segfault while swapping network interface names in udev
375 The group "video" is part of the default rules now.
379 Bugfix for kernels using SYSFS_DEPRECATED* option and finding parent
380 block devices in some cases. No common distro uses this option anymore,
381 and we do not get enough testing for this and recent udev versions. If
382 this option is not needed to run some old distro with a new kernel,
383 it should be disabled in the kernel config.
385 Bugfix for the $links substitution variable, which may crash if no links
386 are created. This should not happen in usual setups because we always
387 create /dev/{block,char}/ links.
389 The strings of the parsed rules, which are kept in memory, no longer
390 contain duplicate entries, or duplicate tails of strings. This, and the
391 new rules parsing/matching code reduces the total in-memory size of
392 a huge distro rule sets to 0.08 MB, compared to the 1.2MB of udev
395 The export of DEVTYPE=disk/partition got removed from the default
396 rules. This value is available from the kernel. The pnp shell script
397 modprobe hack is removed from the default rules. ACPI devices have _proper_
398 modalias support and take care of the same functionality.
399 Installations which support old kernels, but install current default
400 udev rules may want to add that to the compat rules file.
402 Libvolume_id now always probes for all known filesystems, and does not
403 stop at the first match. Some filesystems are marked as "exclusive probe",
404 and if any other filesytem type matches at the same time, libvolume_id
405 will, by default, not return any probing result. This is intended to prevent
406 mis-detection with conflicting left-over signatures found from earlier
407 file system formats. That way, we no longer depend on the probe-order
408 in case of multiple competing signatures. In some setups the kernel allows
409 to mount a volume with just the old filesystem signature still in place.
410 This may damage the new filesystem and cause data-loss, just by mounting
411 it. Because volume_id can not decide which one the correct signature is,
412 the wrong signatures need to be removed manually from the volume, or the
413 volume needs to be reformatted, to enable filesystem detection and possible
418 Fix segfault if compiled without optimization and dbg() does not get
419 compiled out and uses variables which are not available.
423 Bugfixes. (And maybe new bugs. :))
425 The rule matching engine got converted from a rule list to a token
426 array which reduced the in-memory rules representation of a full
427 featured distros with thousends of udev rules from 1.2MB to 0.12 MB.
428 Limits like 5 ENV and ATTR matches, and one single instance for most
429 other keys per rule are gone.
431 The NAME assignment is no longer special cased. If later rules assign
432 a NAME value again, the former value will be overwritten. As usual
433 for most other keys, the NAME value can be protected by doing a final
434 assignment with NAME:="<value>".
436 All udev code now uses libudev, which is also exported. The library
437 is still under development, marked as experimental, and its interface
438 may change as long as the DeviceKit integration is not finished.
440 Many thanks to Alan Jenkins for his continuous help, and finding and
441 optimizing some of the computing expensive parts.
447 Kernel devices and device nodes are connected now by reverse indizes in
448 /sys and /dev. A device number retrieved by a stat() or similar, the
449 kernel device directory can be found by looking up:
450 /sys/dev/{block,char}/<maj>:<min>
451 and the device node of the same device by looking up:
452 /dev/{block,char}/<maj>:<min>
456 Fix recently introduced bug, which caused a compilation without large
457 file support, where vol_id does not recognize raid signatures at the end
460 Firewire disks now create both, by-id/scsi-* and by-id/ieee-* links.
461 Seems some kernel versions prevent the creation of the ieee-* links,
462 so people used the scsi-* link which disappeared now.
464 More libudev work. Almost all udevadm functionality comes from libudev
467 udevadm trigger has a new option --type, which allows to trigger events
468 for "devices", for "subsystems", or "failed" devices. The old option
469 --retry-failed" still works, but is no longer mentioned in the man page.
475 The udevadm info --device-id-of-file= output has changed to use
476 the obvious format. Possible current users should use the --export
477 option which is not affected.
479 The old udev commands symlinks to udevadm are not installed, if
480 these symlinks are used, a warning is printed.
486 Optical drive's media is no longer probed for raid signatures,
487 reading the end of the device causes some devices to malfunction.
488 Also the offset of the last session found is used now to probe
491 The volume_id library got a major version number update to 1,
492 some deprecated functions are removed.
494 A shared library "libudev" gets installed now to provide access
495 to udev device information. DeviceKit, the successor of HAL, will
496 need this library to access the udev database and search sysfs for
498 The library is currently in an experimental state, also the API is
499 expected to change, as long as the DeviceKit integration is not
504 We use ./configure now. See INSTALL for details. Current
507 "/usr" - prefix for man pages, include files
509 "" - the root filesystem, prefix for libs and binaries
513 "lib" - directory name for libraries, not a path name
514 multilib 64bit systems may use "lib64" instead of "lib"
516 compile-in verbose debug messages
518 disable all logging and compile-out all log strings
520 link against SELInux libraries, to set the expected context
523 In the default rules, the group "disk" gets permissions 0660 instead
524 of 0640. One small step closer to unify distro rules. Some day, all
525 distros hopefully end up with the same set of rules.
527 No symlinks to udevadm are installed anymore, if they are still needed,
528 they should be provided by the package.
534 Default udev rules, which are not supposed to be edited by the user, should
535 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
536 the udev package and will be replaced with an update. Udev will pick up rule
538 /lib/udev/rules.d/ - default installed rules
539 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
540 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
541 It does not matter in which directory a rule file lives, all files are sorted
544 To help creating /dev/root, we have now:
545 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
548 In case the current --device-id-of-file is already used, please switch to
549 the --export format version, it saves the output parsing and the old
550 format will be changed to use ':' as a separator, like the format in the
555 Fix cdrom_id to properly recognize blank media.
561 Tape drive id-data is queried from /dev/bsg/* instead of the tape
562 nodes. This avoids rewinding tapes on open().
568 The symlinks udevcontrol and udevtrigger are no longer installed by
571 The scsi_id program does not depend on sysfs anymore. It can speak
572 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
573 data, which should solve some old problems with tape devices, where
574 we better do not open all tape device nodes to identify the device.
580 The cdrom_id program is replaced by an advanced version, which can
581 detect most common device types, and also properties of the inserted
582 media. This is part of moving some basic functionality from HAL into
583 udev (and the kernel).
589 The last WAIT_FOR_SYSFS rule is removed from the default rules.
591 The symlinks to udevadm for the debugging tools: udevmonitor and
592 udevtest are no longer created.
594 The symlinks to the udevadm man page for the old tool names are
597 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
598 should be prefixed with '@' to indicate that the path is not a
609 Udevstart is removed from the tree, it did not get installed for
610 a long time now, and is long replaced by trigger and settle.
616 All udev tools are merged into a single binary called udevadm.
617 The old names of the tools are built-in commands in udevadm now.
618 Symlinks to udevadm, with the names of the old tools, provide
619 the same functionality as the standalone tools. There is also
620 only a single udevadm.8 man page left for all tools.
622 Tools like mkinitramfs should be checked, if they need to include
623 udevadm in the list of files.
633 The etc/udev/rules.d/ directory now contains a default set of basic
634 udev rules. This initial version is the result of a rules file merge
635 of Fedora and openSUSE. For these both distros only a few specific
636 rules are left in their own file, named after the distro. Rules which
637 are optionally installed, because they are only valid for a specific
638 architecture, or rules for subsystems which are not always used are
639 in etc/udev/packages/.
645 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
646 actions by dynamically created rules.
648 SYMLINK=="<value>" matches agains the entries in the list of
649 currently defined symlinks. The links are not created in the
650 filesystem at that point in time, but the values can be matched.
652 RUN{ignore_error}+="<program>" will ignore any exit code from the
653 program and not record as a failed event.
659 Final merge of patches/features from the Ubuntu package.
665 Control characters in filesystem label strings are no longer silenty
666 removed, but hex-encoded, to be able to uniquely identify the device
667 by its symlink in /dev/disk/by-label/.
668 If libvolume_id is used by mount(8), LABEL= will work as expected,
669 if slashes or other characters are used in the label string.
671 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
672 can be specified now. The TEST key accepts an optional mode mask
673 TEST{0100}=="<is executable file>".
675 Scsi_id now supports a mode without expecting scsi-specific sysfs
676 entries to allow the extraction of cciss-device persistent properties.
682 In the future, we may see uuid's which are just simple character
683 strings (see the DDF Raid Specification). For that reason vol_id now
684 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
685 the creation of symlinks, the *_SAFE values ensure, that no control
686 or whitespace characters are used in the filename.
688 Possible users of libvolume_id, please use the volume_id_get_* functions.
689 The public struct will go away in a future release of the library.
695 Removal of useless extras/eventrecorder.sh.
705 The directory multiplexer for dev.d/ and hotplug.d are finally removed
706 from the udev package.
712 Symlinks can have priorities now, the priority is assigned to the device
713 and specified with OPTIONS="link_priority=100". Devices with higher
714 priorities overwrite the symlinks of devices with lower priorities.
715 If the device that currently owns the link, goes away, the symlink
716 will be removed, and recreated, pointing to the next device with the
717 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
718 more reliable, if multiple devices contain the same metadata and overwrite
721 The dasd_id program is removed from the udev tree, and dasdinfo, with the
722 needed rules, are part of the s390-tools now.
724 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
725 we may get the scsi sysfs mess fixed some day, and this will only catch
726 the devices we are looking for.
728 USB serial numbers for storage devices have the target:lun now appended,
729 to make it possibble to distinguish broken multi-lun devices with all
730 the same SCSI identifiers.
732 Note: The extra "run_directory" which searches and executes stuff in
733 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
734 with the next release. Make sure, that you don't use it anymore, or
735 provides your own implementation of that inefficient stuff.
736 We are tired of reports about a "slow udev", because these directories
737 contain stuff, that runs with _every_ event, instead of using rules,
738 that run programs only for the matching events.
748 DRIVER== will match only for devices that actually have a real
749 driver. DRIVERS== must be used, if parent devices should be
750 included in the match.
752 Libvolume_id's "linux_raid" detection needed another fix.
760 Add additional check to volume_id detection of via_raid, cause
761 some company decided to put a matching pattern all over the empty
762 storage area of their music players.
766 Fix path_id for SAS devices.
770 The udev daemon can be started with --debug-trace now, which will
771 execute all events serialized to get a chance to catch a possible
772 action that crashes the box.
774 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
775 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
776 are excluded from the warning. Referencing parent attributes directly
777 may break when something in the kernel driver model changes. Udev will
778 just find the attribute by walking up the parent chain.
780 Udevtrigger now sorts the list of devices depending on the device
781 dependency, so a "usb" device is triggered after the parent "pci"
786 Revert persistent-storage ata-serial '_' '-' replacement.
792 Udevtrigger can now filter the list of devices to be triggered. Matches
793 for subsystems or sysfs attributes can be specified.
795 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
796 zero-sized files to avoid pointing to /sys and confuse broken tools which
797 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
800 The rules and scripts to create udev rules for persistent network
801 devices and optical drives are in the extras/rules_generator directory
802 now. If you use something similar, please consider replacing your own
803 version with this, to share the support effort. The rule_generator
804 installs its own rules into /etc/udev/rules.d.
806 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
807 the rule_generator depends on cdrom_id to be called in an earlier rule.
813 Renaming of some key names (the old names still work):
814 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
815 (The behavior of the key DRIVER will change soon in one of the next
816 releases, to match only the event device, please switch to DRIVERS
817 instead. If DRIVER is used, it will behave like DRIVERS, but an error
819 With the new key names, we have a more consistent and simpler scheme.
820 We can match the properties of the event device only, with: KERNEL,
821 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
822 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
823 longer mentioned in the man page and should be switched in the rule
826 ATTR{file}="value" can be used now, to write to a sysfs file of the
827 event device. Instead of:
828 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
830 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
832 All the PHYSDEV* keys are deprecated and will be removed from a
834 PHYDEVPATH - is the path of a parent device and should not be
836 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
837 matched with SUBSYSTEMS==
838 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
839 Newer kernels will have DRIVER in the environment,
840 for older kernels udev puts in. Class device will
841 no longer carry this property of a parent and
842 DRIVERS== can be used to match such a parent value.
843 Note that ENV{DRIVER} is only available for a few bus devices, where
844 the driver is already bound at device event time. On coldplug, the
845 events for a lot devices are already bound to a driver, and they will have
846 that value set. But on hotplug, at the time the kernel creates the device,
847 it can't know what driver may claim the device after that, therefore
848 in most cases it will be empty.
850 Failed events should now be re-triggered with:
851 udevtrigger --retry-failed.
852 Please switch to this command, so we keep the details of the /dev/.udev/failed/
853 files private to the udev tools. We may need to switch the current symlink
854 target, cause some obviously broken tools try to scan all files in /dev
855 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
856 million times. This takes ages on slow boxes.
858 The udevinfo attribute walk (-a) now works with giving a device node
859 name (-n) instead of a devpath (-p). The query now always works, also when
860 no database file was created by udev.
862 The built-in /etc/passwd /etc/group parser is removed, we always depend on
863 getpwnam() and getgrnam() now. One of the next releases will depend on
864 fnmatch() and may use getopt_long().
868 Bugfixes and small improvements.
872 Fix path_id for recent kernels.
878 Added support for swapping network interface names, by temporarily
879 renaming the device and wait for the target name to become free.
883 The built-in MODALIAS key and substitution is removed.
887 The binary firmware helper is replaced by the usual simple
888 shell script. Udevsend is removed from the tree.
896 Some more keys require the correct use of '==' and '=' depending
897 on the kind of operation beeing an assignment or a match. Rules
898 with invalid operations are skipped and logged to syslog. Please
899 test with udevtest if the parsing of your rules throws errors and
900 fix possibly broken rules.
904 Provide "udevsettle" to wait for all current udev events to finish.
905 It also watches the current kernel netlink queue by comparing the
906 even sequence number to make sure that there are no current pending
907 events that have not already arrived in the daemon.
911 Fix rule to skip persistent rules for removable IDE devices, which
912 also skipped optical IDE drives.
914 All *_id program are installed in /lib/udev/ by default now.
916 No binary is stripped anymore as this should be done in the
917 packaging process and not at build time.
919 libvolume_id is provided as a shared library now and vol_id is
920 linked against it. Also one of the next HAL versions will require
921 this library, and the HAL build process will also require the
922 header file to be installed. The copy of the same code in HAL will
923 be removed to have only a single copy left on the system.
927 Add persistent links for SCSI tapes. The rules file is renamed
928 to 60-persistent-storage.rules.
930 Create persistent path for usb devices. Can be used for all sorts
931 of devices that can't be distinguished by other properties like
932 multiple identical keyboards and mice connected to the same box.
934 Provide "udevtrigger" program to request events on coldplug. The
935 shell script is much too slow with thousends of devices.
939 Fix persistent disk rules to exclude removable IDE drives.
941 Warn if %e, $modalias or MODALIAS is used.
945 Fix queue export, which wasn't correct for subsequent add/remove
946 events for the same device.
950 Fix cramfs detection on big endian.
952 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
957 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
958 attributes were only checked at the parent device that matched the
959 by BUS requested subsystem. Fix it to also look at the device we
960 received the event for.
962 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
967 Fix a bug where NAME="" would prevent RUN from beeing executed.
969 RUN="/bin/program" does not longer automatically add the subsystem
970 as the first parameter. This is from the days of /sbin/hotplug
971 which is dead now and it's just confusing to need to add a space at
972 the end of the program name to prevent this.
973 If you use rules that need the subsystem as the first parameter,
974 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
975 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
979 The udev man page has moved to udev(7) as it does not describe a command
980 anymore. The programs udev, udevstart and udevsend are no longer installed
981 by default and must be copied manually, if they should be installed or
982 included in a package.
984 Fix a bug where "ignore_device" could run earlier collected RUN keys before
985 the ignore rule was applied.
987 More preparation for future sysfs changes. usb_id and scsi_id no longer
988 depend on a magic order of devices in the /devices chain. Specific devices
989 should be requested by their subsytem.
991 This will always find the scsi parent device without depending on a specific
993 dev = sysfs_device_get(devpath);
994 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
996 The "device" link in the current sysfs layout will be automatically
997 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
998 parent in the devpath. If a device is requested by it's symlink, like all
999 class devices in the new sysfs layout will look like, it gets automatically
1000 resolved and substituted with the real devpath and not the symlink path.
1003 A similar logic must be applied to _all_ sysfs users, including
1004 scripts, that search along parent devices in sysfs. The explicit use of
1005 the "device" link must be avoided. With the future sysfs layout all
1006 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
1007 back to the "class" or the "bus". The layout of the parent devices in
1008 /devices is not necessarily expected to be stable across kernel releases and
1009 searching for parents by their subsystem should make sysfs users tolerant
1010 for changed parent chains.
1014 Prepare udev to work with the experimental kernel patch, that moves
1015 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
1017 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
1018 moving the class devices to /sys/devices.
1020 Thanks again to Marco for help finding a hopefully nice compromise
1021 to make %b simpler and working again.
1025 Complete removal of libsysfs, replaced by simple helper functions
1026 which are much simpler and a bit faster. The udev daemon operatesentirely
1027 on event parameters and does not use sysfs for simple rules anymore.
1028 Please report any new bugs/problems, that may be caused by this big
1029 change. They will be fixed immediately.
1031 The enumeration format character '%e' is deprecated and will be
1032 removed sometimes from a future udev version. It never worked correctly
1033 outside of udevstart, so we can't use it with the new parallel
1034 coldplug. A simple enumeration is as useless as the devfs naming
1035 scheme, just get rid of both if you still use it.
1037 MODALIAS and $modalias is not needed and will be removed from one of
1038 the next udev versions, replace it in all rules with ENV{MODALIAS} or
1039 the sysfs "modalias" value.
1041 Thanks a lot to Marco for all his help on finding and fixing bugs.
1045 Let scsi_id request libata drive serial numbers from page 0x80.
1047 Renamed etc/udev/persistent.rules to persistent-disk.rules and
1048 added /dev/disk/by-name/* for device mapper device names.
1050 Removed %e from the man page. It never worked reliably outside
1051 of udevstart and udevstart is no longer recommended to use.
1055 Symlinks are now exported to the event environment. Hopefully it's no
1056 longer needed to run udevinfo from an event process, like it was
1057 mentioned on the hotplug list:
1058 UDEV [1134776873.702967] add@/block/sdb
1061 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
1065 Fix a problem if udevsend is used as the hotplug handler and tries to use
1066 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
1067 and this kind of problems will hopefully go away soon.
1071 All built-in logic to work around bad sysfs timing is removed with this
1072 version. The need to wait for sysfs files is almost fixed with a kernel
1073 version that doesn't work with this udev version anyway. Until we fix
1074 the timing of the "bus" link creation, the former integrated logic should
1075 be emulated by a rule placed before all other rules:
1076 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
1078 The option "udev_db" does no longer exist. All udev state will be in
1079 /$udev_root/.udev/ now, there is no longer an option to set this
1081 If the init script or something else used this value, just depend on
1082 this hardcoded path. But remember _all_content_ of this directory is
1083 still private to udev and can change at any time.
1085 Default location for rule sripts and helper programs is now: /lib/udev/.
1086 Everything that is not useful on the commandline should go into this
1087 directory. Some of the helpers in the extras folder are installed there
1088 now. The rules need to be changed, to find the helpers there.
1090 Also /lib/udev/devices is recommended as a directory where packages or
1091 the user can place real device nodes, which get copied over to /dev at
1092 every boot. This should replace the various solutions with custom config
1095 Udevsend does no longer start the udev daemon. This must be done with
1096 the init script that prepares /dev on tmpfs and creates the initial nodes,
1097 before starting the daemon.
1101 Silent a too verbose error logging for the old hotplug.d/ dev.d/
1104 The copy of klibc is removed. A systemwide installed version of klibc
1105 should be used to build a klibc udev now.
1109 NAME="" will not create any nodes, but execute RUN keys. To completely
1110 ignore an event the OPTION "ignore_device" should be used.
1112 After removal of the reorder queue, events with a TIMEOUT can be executed
1113 without any queuing now.
1117 Fixed bug in udevd, if inotify is not available. We depend on netlink
1118 uevents now, kernels without that event source will not work with that
1119 version of udev anymore.
1123 The rule parsing happens now in the daemon once at startup, all udev
1124 event processes inherit the already parsed rules from the daemon.
1125 It is shipped with SUSE10.0 and reduces heavily the system load at
1126 startup. The option to save precompiled rules and let the udev process
1127 pick the them up is removed, as it's no longer needed.
1129 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
1130 device. Libsysfs is changed to "translate" the requested link into the
1131 real device path, as it would happen with the hotplug event. Otherwise
1132 device removal and the udev database will not work.
1134 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
1137 A few improvements for vol_id, the filesytem probing code.
1141 Fix a stupid typo in extras/run_directory for "make install".
1143 scsi_id creates the temporary devnode now in /dev for usage with a
1144 non-writable /tmp directory.
1146 The uevent kernel socket buffer can carry app. 50.000 events now,
1147 let's see who can break this again. :)
1149 The upcoming kernel will have a new input driver core integration.
1150 Some class devices are now symlinks to the real device. libsysfs
1151 needs a fix for this to work correctly. Udevstart of older udev
1152 versions will _not_ create these devices!
1156 Fix a 'install' target in the Makefile, that prevents EXTRAS from
1161 A bunch of mostly trivial bugfixes. From now on no node name or
1162 symlink name can contain any character than plain whitelisted ascii
1163 characters or validated utf8 byte-streams. This is needed for the
1164 /dev/disk/by-label/* links, because we import untrusted data and
1165 export it to the filesystem.
1169 More bugfixes. If udevd was started from the kernel, we don't
1170 have stdin/stdout/stderr, which broke the forked tools in some
1175 Bugfix. udevstart event ordering was broken for a long time.
1176 The new run_program() uncovered it, because /dev/null was not
1177 available while we try to run external programs.
1178 Now udevstart should create it before we run anything.
1182 Minor bugfixes and some distro rules updates. If you don't have the
1183 persistent disk rules in /dev/disk/by-*/* on your distro, just
1184 grab it from here. :)
1188 We can use socket communication now to pass events from udev to
1190 RUN+="socket:/org/freedesktop/hal/udev_event"
1191 will pass the whole udev event to the HAL daemon without the need
1192 for a forked helper. (See ChangeLog for udevmonitor, as an example)
1196 Mostly bugfixes and see ChangeLog.
1198 The test for the existence of an environment value should be
1200 ENV{KEY}=="*" to ENV{KEY}=="?*"
1201 because "*" will not fail anymore, if the key does not exist or
1206 Bugfixes and a few tweaks described in the ChangeLog.
1210 Mostly a Bugfix release.
1212 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
1213 timing with custom rules.
1217 We changed the internal rule storage format. Our large rule files took
1218 2 MB of RAM, with the change we are down to 99kB.
1220 If the device-node has been created with default name and no symlink or
1221 options are to remenber, it is not longer stored in the udevdb. HAL will
1222 need to be updated to work correctly with that change.
1224 To overrride optimization flags, OPTFLAGS may be used now.
1232 Major changes happened with this release. The goal is to take over the
1233 complete kernel-event handling and provide a more efficient way to dispatch
1234 kernel events. Replacing most of the current shell script logic and the
1235 kernel forked helper with a netlink-daemon and a rule-based event handling.
1237 o udevd listens to netlink events now. The first valid netlink event
1238 will make udevd ignore any message from udevsend that contains a
1239 SEQNUM, to avoid duplicate events. The forked events can be disabled
1241 echo "" > /proc/sys/kernel/hotplug
1242 For full support, the broken input-subsytem needs to be fixed, not to
1243 bypass the driver core.
1245 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
1246 removed from udev itself and must be emulated by calling small
1247 helper binaries provided in the extras folder:
1248 make EXTRAS=extras/run_directory/
1249 will build udev_run_devd and udev_run_hotplugd, which can be called
1250 from a rule if needed:
1251 RUN+="/sbin/udev_run_hotplugd"
1252 The recommended way to handle this is to convert all the calls from
1253 the directories to explicit udev rules and get completely rid of the
1254 multiplexing. (To catch a ttyUSB event, you now no longer need to
1255 fork and exit 300 tty script instances you are not interested in, it
1256 is just one rule that matches exactly the device.)
1258 o udev handles now _all_ events not just events for class and block
1259 devices, this way it is possible to control the complete event
1260 behavior with udev rules. Especially useful for rules like:
1261 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
1263 o As used in the modalias rule, udev supports now textual
1264 substitution placeholder along with the usual format chars. This
1265 needs to be documented, for now it's only visible in udev_rules_parse.c.
1267 o The rule keys support now more operations. This is documented in the
1268 man page. It is possible to add values to list-keys like the SYMLINK
1269 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
1270 Also "final"-assignments are supported by using KEY:="value", which will
1271 prevent changing the key by any later rule.
1273 o kernel 2.6.12 has the "detached_state" attribute removed from
1274 sysfs, which was used to recognize sysfs population. We switched that
1275 to wait for the "bus" link, which is only available in kernels after 2.6.11.
1276 Running this udev version on older kernels may cause a short delay for
1279 o To provide infrastructure for persistent device naming, the id programs:
1280 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
1281 to export the probed data in environment key format:
1282 pim:~ # /sbin/ata_id --export /dev/hda
1283 ID_MODEL=HTS726060M9AT00
1284 ID_SERIAL=MRH401M4G6UM9B
1285 ID_REVISION=MH4OA6BA
1287 The following rules:
1288 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
1289 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
1292 kay@pim:~> tree /dev/disk
1295 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
1296 | `-- IBM-Memory_Key -> ../../sda
1298 | |-- swap -> ../../hda1
1299 | |-- date -> ../../sda1
1300 | `-- home -> ../../hda3
1302 |-- 2E08712B0870F2E7 -> ../../hda3
1303 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
1304 |-- E845-7A89 -> ../../sda1
1305 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
1307 The IMPORT= operation will import these keys in the environment and make
1308 it available for later PROGRAM= and RUN= executed programs. The keys are
1309 also stored in the udevdb and can be queried from there with one of the
1312 o A few binaries are silently added to the repository, which can be used
1313 to replay kernel events from initramfs instead of using coldplug. udevd
1314 can be instructed now to queue-up events while the stored events from
1315 initramfs are filled into the udevd-queue. This code is still under
1316 development and there is no documentation now besides the code itself.
1317 The additional binaries get compiled, but are not installed by default.
1319 o There is also a temporary fix for a performance problem where too many
1320 events happen in parallel and every event needs to parse the rules.
1321 udev can now read precompiled rules stored on disk. This is likely to be
1322 replaced by a more elegant solution in a future udev version.
1326 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
1327 Fix for libsysfs not to expect this file was added.
1331 All rules are applied now, but only the first matching rule with a NAME-key
1332 will be applied. All later rules with NAME-key are completely ignored. This
1333 way system supplied symlinks or permissions gets applied to user-defined
1337 Please check your rules setup, if you may need to add OPTIONS="last_rule"
1338 to some rules, to keep the old behavior.
1340 The rules are read on "remove"-events too. That makes is possible to match
1341 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
1342 instruct udev to ignore an event (OPTIONS="ignore_device").
1343 The new ACTION-key may be used to let a rule act only at a "remove"-event.
1345 The new RUN-key supports rule-based execution of programs after device-node
1346 handling. This is meant as a general replacement for the dev.d/-directories
1347 to give fine grained control over the execution of programs.
1349 The %s{}-sysfs format char replacement values are searched at any of the
1350 devices in the device chain now, not only at the class-device.
1352 We support log priority levels now. The value udev_log in udev.conf is used
1353 to determine what is printed to syslog. This makes it possible to
1354 run a version with compiled-in debug messages in a production environment
1355 which is sometimes needed to find a bug.
1356 It is still possible to supress the inclusion of _any_ syslog usage with
1357 USE_LOG=false to create the smallest possible binaries if needed.
1358 The configured udev_log value can be overridden with the environment variable
1363 Possible use of a system-wide klibc:
1364 make USE_KLIBC=true KLCC=/usr/bin/klcc all
1365 will link against an external klibc and our own version will be ignored.
1369 We support an unlimited count of symlinks now.
1371 If USE_STATIC=true is passed to a glibc build, we link statically and use
1372 a built-in userdb parser to resolve user and group names.
1374 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
1375 we walk up the chain of physical devices to find a match.
1377 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
1378 easy to skip certain attribute matches without composing rules with weird
1379 character class negations like:
1380 KERNEL="[!s][!c][!d]*"
1381 this can now be replaced with:
1383 The current simple '=' is still supported, and should work as it does today,
1384 but existing rules should be converted if possible, to be better readable.
1386 We have new ENV{}== key now, to match against a maximum of 5 environment
1389 udevstart is its own binary again, because we don't need co carry this araound
1390 with every forked event.