5 warning if /run is not writable.
9 udevadm info --cleanup-db
11 systemd netlink socket activation
12 stop socket or mask on rpm update
19 The udev runtime data moved from /dev/.udev/ to /run/udev/. The
20 /run mountpoint is supposed to be a tmpfs mounted during early boot,
21 available and writable to for all tools at any time during bootup,
22 it replaces /var/run/, which should become a symlink some day.
24 If /run does not exist, or is not writable, udev will fall back using
27 On systemd systems with initramfs and LVM used, packagers must
28 make sure, that the systemd and initramfs versions match. The initramfs
29 needs to create the /run mountpoint for udev to store the data, and
30 mount this tmpfs to /run in the rootfs, so the that the udev database
31 is preserved for the udev version started in the rootfs.
33 The command 'udevadm info --convert-db' is gone. The udev daemon
34 itself, at startup, converts any old database version if necessary.
36 The systemd services files have been reorganized. The udev control
37 socket is bound by systemd and passed to the started udev daemon.
38 The udev-settle.service is no longer active by default. Services which
39 can not handle hotplug setups properly need to actively pull it in, to
40 act like a barrier. Alternatively the settle service can be unconditionally
41 'systemctl'enabled, and act like a barrier for basic.target.
43 The fstab_import callout is no longer built or installed. Udev
44 should not be used to mount, does not watch changes to fstab, and
45 should not mirror fstab values in the udev database.
51 New and updated keymaps.
57 The udev database has changed, After installation of a new udev
58 version, 'udevadm info --convert-db' should be called, to let the new
59 udev/libudev version read the already stored data.
61 udevadm now supports quoting of property values, and prefixing of
63 $ udevadm info --export --export-prefix=MY_ --query=property -n sda
71 udev_device_get_is_initialized()
72 udev_enumerate_add_match_is_initialized()
73 to be able to skip devices the kernel has created , but udev has
77 udev_device_get_usec_since_initialized()
78 to retrieve the "age" of a udev device record.
80 GUdev supports a more generic GUdevEnumerator class, udev TAG
81 handling, device initialization and timestamp now.
83 The counterpart of /sys/dev/{char,block}/$major:$minor,
84 /dev/{char,block}/$major:$minor symlinks are now unconditionally
85 created, even when no rule files exist.
87 New and updated keymaps.
93 GUdev moved from /usr to /.
103 Persistent network naming rules are disabled inside of Qemu/KVM now.
105 New and updated keymaps.
107 Udev gets unconditionally enabled on systemd installations now. There
108 is no longer the need to to run 'systemctl enable udev.service'.
122 New and fixed keymaps.
124 Install systemd service files if applicable.
130 All distribution specific rules are removed from the udev source tree,
131 most of them are no longer needed. The Gentoo rules which allow to support
132 older kernel versions, which are not covered by the default rules anymore
133 has moved to rules/misc/30-kernel-compat.rules.
139 The option --debug-trace and the environemnt variable UDEVD_MAX_CHILDS=
140 was removed from udevd.
142 Udevd now checks the kernel commandline for the following variables:
143 udev.log-priority=<syslog priority>
144 udev.children-max=<maximum number of workers>
145 udev.exec-delay=<seconds to delay the execution of RUN=>
146 to help debuging coldplug setups where the loading of a kernel
147 module crashes the system.
149 The subdirectory in the source tree rules/packages has been renamed to
150 rules/arch, anc contains only architecture specific rules now.
160 Now the udev daemon itself, does on startup:
161 - copy the content of /lib/udev/devices to /dev
162 - create the standard symlinks like /dev/std{in,out,err},
163 /dev/core, /dev/fd, ...
164 - use static node information provided by kernel modules
165 and creates these nodes to allow module on-demand loading
166 - possibly apply permissions to all ststic nodes from udev
167 rules which are annotated to match a static node
169 The default mode for a device node is 0600 now to match the kernel
170 created devtmpfs defaults. If GROUP= is specified and no MODE= is
171 given the default will be 0660.
177 Udev now gradually starts to pass control over the primary device nodes
178 and their names to the kernel, and will in the end only manage the
179 permissions of the node, and possibly create additional symlinks.
180 As a first step NAME="" will be ignored, and NAME= setings with names
181 other than the kernel provided name will result in a logged warning.
182 Kernels that don't provide device names, or devtmpfs is not used, will
183 still work as they did before, but it is strongly recommended to use
184 only the same names for the primary device node as the recent kernel
185 provides for all devices.
189 Fix broken firmware loader search path.
195 "udevadm trigger" defaults to "change" events now instead of "add"
196 events. The "udev boot script" might need to add "--action=add" to
197 the trigger command if not already there, in case the initial coldplug
198 events are expected as "add" events.
200 The option "all_partitons" was removed from udev. This should not be
201 needed for usual hardware. Udev can not safely make assumptions
202 about non-existing partition major/minor numbers, and therefore no
203 longer provide this unreliable and unsafe option.
205 The option "ignore_remove" was removed from udev. With devtmpfs
206 udev passed control over device nodes to the kernel. This option
207 should not be needed, or can not work as advertised. Neither
208 udev nor the kernel will remove device nodes which are copied from
209 the /lib/udev/devices/ directory.
211 All "add|change" matches are replaced by "!remove" in the rules and
212 in the udev logic. All types of events will update possible symlinks
213 and permissions, only "remove" is handled special now.
215 The modem modeswitch extra was removed and the external usb_modeswitch
216 program should be used instead.
218 New and fixed keymaps.
228 Kernels with SYSFS_DEPRECATED=y are not supported since a while. Many users
229 depend on the current sysfs layout and the information not available in the
230 deprecated layout. All remaining support for the deprecated sysfs layout is
235 Fix for a possible endless loop in the new input_id program.
241 The option "ignore_device" does no longer exist. There is no way to
242 ignore an event, as libudev events can not be suppressed by rules.
243 It only prevented RUN keys from being executed, which results in an
244 inconsistent behavior in current setups.
246 BUS=, SYSFS{}=, ID= are long deprecated and should be SUBSYSTEM(S)=,
247 ATTR(S){}=, KERNEL(S)=. It will cause a warning once for every rule
250 The support for the deprecated IDE devices has been removed from the
251 default set of rules. Distros who still care about non-libata drivers
252 need to add the rules to the compat rules file.
254 The ID_CLASS property on input devices has been replaced by the more accurate
255 set of flags ID_INPUT_{KEYBOARD,KEY,MOUSE,TOUCHPAD,TABLET,JOYSTICK}. These are
256 determined by the new "input_id" prober now. Some devices, such as touchpads,
257 can have several classes. So if you previously had custom udev rules which e. g.
258 checked for ENV{ID_CLASS}=="kbd", you need to replace this with
259 ENV{ID_INPUT_KEYBOARD}=="?*".
265 To support DEVPATH strings larger than the maximum file name length, the
266 private udev database format has changed. If some software still reads the
267 private files in /dev/.udev/, which it shouldn't, now it's time to fix it.
268 Please do not port anything to the new format again, everything in /dev/.udev
269 is and always was private to udev, and may and will change any time without
272 Multiple devices claiming the same names in /dev are limited to symlinks
273 only now. Mixing identical symlink names and node names is not supported.
274 This reduces the amount of data in the database significantly.
276 NAME="%k" causes a warning now. It's is and always was completely superfluous.
277 It will break kernel supplied DEVNAMEs and therefore it needs to be removed
280 Most NAME= instructions got removed. Kernel 2.6.31 supplies the needed names
281 if they are not the default. To support older kernels, the NAME= rules need to
282 be added to the compat rules file.
284 Symlinks to udevadm with the old command names are no longer resolved to
285 the udevadm commands.
287 The udev-acl tool got adopted to changes in ConsoleKit. Version 0.4.1 is
290 The option "last_rule" does no longer exist. Its use breaks too many
291 things which expect to be run from independent later rules, and is an idication
292 that something needs to be fixed properly instead.
294 The gudev API is no longer marked as experimental,
295 G_UDEV_API_IS_SUBJECT_TO_CHANGE is no longer needed. The gudev introspection
296 is enabled by default now. Various projects already depend on introspection
297 information to bind dynamic languages to the gudev interfaces.
303 The udevadm trigger "--retry-failed" option, which is replaced since quite
304 a while by "--type=failed" is removed.
306 The failed tracking was not working at all for a few releases. The RUN
307 option "ignore_error" is replaced by a "fail_event_on_error" option, and the
308 default is not to track any failing RUN executions.
310 New keymaps, new modem, hid2hci updated.
314 Fix possible crash in udevd when worker processes are busy, rules are
315 changed at the same time, and workers get killed to reload the rules.
321 Properties set with ENV{.FOO}="bar" are marked private by starting the
322 name with a '.'. They will not be stored in the database, and not be
323 exported with the event.
325 Firmware files are looked up in:
326 /lib/firmware/updates/$(uname -r)
327 /lib/firmware/updates
328 /lib/firmware/$(uname -r)
332 ATA devices switched the property from ID_BUS=scsi to ID_BUS=ata.
333 ata_id, instead of scsi_id, is the default tool now for ATA devices.
339 The configure options have changed because another library needs to be
340 installed in a different location. Instead of exec_prefix and udev_prefix,
341 libdir, rootlibdir and libexecdir are used. The Details are explained in
344 Event processes now get re-used after they handled an event. This reduces
345 the number of forks and the pressure on the CPU significantly, because
346 cloned event processes no longer cause page faults in the main daemon.
347 After the events have settled, a few worker processes stay around for
348 future events, all others get cleaned up.
350 To be able to use signalfd(), udev depends on kernel version 2.6.25 now.
351 Also inotify support is mandatory now to run udev.
353 The format of the queue exported by the udev damon has changed. There is
354 no longer a /dev/.udev/queue/ directory. The current event queue can be
355 accessed with udevadm settle and libudedv.
357 Libudev does not have the unstable API header anymore. From now on,
358 incompatible changes will be handled by bumping the library major version.
360 To build udev from the git tree gtk-doc is needed now. The tarballs will
361 build without it and contain the pre-built documentation. An online copy
363 http://www.kernel.org/pub/linux/utils/kernel/hotplug/libudev/
365 The tools from the udev-extras repository have been merged into the main
366 udev repository. Some of the extras have larger external dependencies, and
367 they can be disabled with the configure switch --disable-extras.
373 The program vol_id and the library libvolume_id are removed from the
374 repository. Libvolume_id is merged with libblkid from the util-linux-ng
375 package. Persistent disk links for label and uuid depend on the
376 util-linux-ng version (2.15) of blkid now. Older versions of blkid
377 can not be used with udev.
379 Libudev allows to subscribe to udev events. To prevent unwanted messages
380 to be delivered, and waking up the subscribing process, a filter can be
381 installed, to drop messages inside a kernel socket filter. The filters
382 match on the <subsytem>:<devtype> properties of the device.
383 This is part of the ongoing effort to replace HAL, and switch current
384 users over to directly use libudev.
385 Libudev is still marked as experimental, and its interface might
386 eventually change if needed, but no major changes of the currently exported
387 interface are expected anymore, and a first stable release should happen
390 A too old kernel (2.6.21) or a kernel with CONFIG_SYSFS_DEPRECATED
391 is not supported since while and udevd will log an error message at
392 startup. It should still be able to boot-up, but advanced rules and system
393 services which depend on the information not available in the old sysfs
394 format will fail to work correctly.
396 DVB device naming is supplied by the kernel now. In case older kernels
397 need to be supported, the old shell script should be added to a compat
404 The processed udev events get send back to the netlink socket. Libudev
405 provides access to these events. This is work-in-progress, to replace
406 the DeviceKit daemon functionality directly with libudev. There are
407 upcoming kernel changes to allow non-root users to subcribe to these
414 "udevadm settle" now optionally accepts a range of events to wait for,
415 instead of waiting for "all" events.
421 The installed watch for block device metadata changes is now removed
422 during event hadling, because some (broken) tools may be called from udev
423 rules and (wrongly) open the device with write access. After the finished
424 event handling the watch is restored.
430 Device nodes can be watched for changes with inotify with OPTIONS="watch".
431 If closed after being opened for writing, a "change" uevent will occur.
432 /dev/disk/by-{label,uuid}/* symlinks will be automatically updated.
438 The udevadm test command has no longer a --force option, nodes and symlinks
439 are always updated with a test run now.
441 The udevd daemon can be started with --resolve-names=never to avoid all user
442 and group lookups (e.g. in cut-down systems) or --resolve-names=late to
443 lookup user and groups every time events are handled.
449 We are currently merging the Ubuntu rules in the udev default rules,
450 and get one step closer to provide a common Linux /dev setup, regarding
451 device names, symlinks, and default device permissions. On udev startup,
452 we now expect the following groups to be resolvable to their ids with
454 disk, cdrom, floppy, tape, audio, video, lp, tty, dialout, kmem.
455 LDAP setups need to make sure, that these groups are always resolvable at
456 bootup, with only the rootfs mounted, and without network access available.
458 Some systems may need to add some new, currently not used groups, or need
459 to add some users to new groups, but the cost of this change is minimal,
460 compared to the pain the current, rather random, differences between the
461 various distributions cause for upstream projects and third-party vendors.
463 In general, "normal" users who log into a machine should never be a member
464 of any such group, but the device-access should be managed by dynamic ACLs,
465 which get added and removed for the specific users on login/logout and
466 session activity/inactivity. These groups are only provided for custom setups,
467 and mainly system services, to allow proper privilege separation.
468 A video-streaming daemon uid would be a member of "audio" and "video", to get
469 access to the sound and video devices, but no "normal" user should ever belong
470 to the "audio" group, because he could listen to the built-in microphone with
471 any ssh-session established from the other side of the world.
473 /dev/serial/by-{id,path}/ now contains links for ttyUSB devices,
474 which do not depend on the kernel device name. As usual, unique
475 devices - only a single one per product connected, or a real
476 USB serial number in the device - are always found with the same
477 name in the by-id/ directory.
478 Completely identical devices may overwrite their names in by-id/
479 and can only be found reliably in the by-path/ directory. Devices
480 specified by by-path/ must not change their connection, like the
481 USB port number they are plugged in, to keep their name.
483 To support some advanced features, Linux 2.6.22 is the oldest supported
484 version now. The kernel config with enabled SYSFS_DEPRECATED is no longer
485 supported. Older kernels should still work, and devices nodes should be
486 reliably created, but some rules and libudev will not work correctly because
487 the old kernels do not provide the expected information or interfaces.
493 Fix for a possible segfault while swapping network interface names in udev
500 The group "video" is part of the default rules now.
504 Bugfix for kernels using SYSFS_DEPRECATED* option and finding parent
505 block devices in some cases. No common distro uses this option anymore,
506 and we do not get enough testing for this and recent udev versions. If
507 this option is not needed to run some old distro with a new kernel,
508 it should be disabled in the kernel config.
510 Bugfix for the $links substitution variable, which may crash if no links
511 are created. This should not happen in usual setups because we always
512 create /dev/{block,char}/ links.
514 The strings of the parsed rules, which are kept in memory, no longer
515 contain duplicate entries, or duplicate tails of strings. This, and the
516 new rules parsing/matching code reduces the total in-memory size of
517 a huge distro rule sets to 0.08 MB, compared to the 1.2MB of udev
520 The export of DEVTYPE=disk/partition got removed from the default
521 rules. This value is available from the kernel. The pnp shell script
522 modprobe hack is removed from the default rules. ACPI devices have _proper_
523 modalias support and take care of the same functionality.
524 Installations which support old kernels, but install current default
525 udev rules may want to add that to the compat rules file.
527 Libvolume_id now always probes for all known filesystems, and does not
528 stop at the first match. Some filesystems are marked as "exclusive probe",
529 and if any other filesytem type matches at the same time, libvolume_id
530 will, by default, not return any probing result. This is intended to prevent
531 mis-detection with conflicting left-over signatures found from earlier
532 file system formats. That way, we no longer depend on the probe-order
533 in case of multiple competing signatures. In some setups the kernel allows
534 to mount a volume with just the old filesystem signature still in place.
535 This may damage the new filesystem and cause data-loss, just by mounting
536 it. Because volume_id can not decide which one the correct signature is,
537 the wrong signatures need to be removed manually from the volume, or the
538 volume needs to be reformatted, to enable filesystem detection and possible
543 Fix segfault if compiled without optimization and dbg() does not get
544 compiled out and uses variables which are not available.
548 Bugfixes. (And maybe new bugs. :))
550 The rule matching engine got converted from a rule list to a token
551 array which reduced the in-memory rules representation of a full
552 featured distros with thousends of udev rules from 1.2MB to 0.12 MB.
553 Limits like 5 ENV and ATTR matches, and one single instance for most
554 other keys per rule are gone.
556 The NAME assignment is no longer special cased. If later rules assign
557 a NAME value again, the former value will be overwritten. As usual
558 for most other keys, the NAME value can be protected by doing a final
559 assignment with NAME:="<value>".
561 All udev code now uses libudev, which is also exported. The library
562 is still under development, marked as experimental, and its interface
563 may change as long as the DeviceKit integration is not finished.
565 Many thanks to Alan Jenkins for his continuous help, and finding and
566 optimizing some of the computing expensive parts.
572 Kernel devices and device nodes are connected now by reverse indizes in
573 /sys and /dev. A device number retrieved by a stat() or similar, the
574 kernel device directory can be found by looking up:
575 /sys/dev/{block,char}/<maj>:<min>
576 and the device node of the same device by looking up:
577 /dev/{block,char}/<maj>:<min>
581 Fix recently introduced bug, which caused a compilation without large
582 file support, where vol_id does not recognize raid signatures at the end
585 Firewire disks now create both, by-id/scsi-* and by-id/ieee-* links.
586 Seems some kernel versions prevent the creation of the ieee-* links,
587 so people used the scsi-* link which disappeared now.
589 More libudev work. Almost all udevadm functionality comes from libudev
592 udevadm trigger has a new option --type, which allows to trigger events
593 for "devices", for "subsystems", or "failed" devices. The old option
594 --retry-failed" still works, but is no longer mentioned in the man page.
600 The udevadm info --device-id-of-file= output has changed to use
601 the obvious format. Possible current users should use the --export
602 option which is not affected.
604 The old udev commands symlinks to udevadm are not installed, if
605 these symlinks are used, a warning is printed.
611 Optical drive's media is no longer probed for raid signatures,
612 reading the end of the device causes some devices to malfunction.
613 Also the offset of the last session found is used now to probe
616 The volume_id library got a major version number update to 1,
617 some deprecated functions are removed.
619 A shared library "libudev" gets installed now to provide access
620 to udev device information. DeviceKit, the successor of HAL, will
621 need this library to access the udev database and search sysfs for
623 The library is currently in an experimental state, also the API is
624 expected to change, as long as the DeviceKit integration is not
629 We use ./configure now. See INSTALL for details. Current
632 "/usr" - prefix for man pages, include files
634 "" - the root filesystem, prefix for libs and binaries
638 "lib" - directory name for libraries, not a path name
639 multilib 64bit systems may use "lib64" instead of "lib"
641 compile-in verbose debug messages
643 disable all logging and compile-out all log strings
645 link against SELInux libraries, to set the expected context
648 In the default rules, the group "disk" gets permissions 0660 instead
649 of 0640. One small step closer to unify distro rules. Some day, all
650 distros hopefully end up with the same set of rules.
652 No symlinks to udevadm are installed anymore, if they are still needed,
653 they should be provided by the package.
659 Default udev rules, which are not supposed to be edited by the user, should
660 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
661 the udev package and will be replaced with an update. Udev will pick up rule
663 /lib/udev/rules.d/ - default installed rules
664 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
665 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
666 It does not matter in which directory a rule file lives, all files are sorted
669 To help creating /dev/root, we have now:
670 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
673 In case the current --device-id-of-file is already used, please switch to
674 the --export format version, it saves the output parsing and the old
675 format will be changed to use ':' as a separator, like the format in the
680 Fix cdrom_id to properly recognize blank media.
686 Tape drive id-data is queried from /dev/bsg/* instead of the tape
687 nodes. This avoids rewinding tapes on open().
693 The symlinks udevcontrol and udevtrigger are no longer installed by
696 The scsi_id program does not depend on sysfs anymore. It can speak
697 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
698 data, which should solve some old problems with tape devices, where
699 we better do not open all tape device nodes to identify the device.
705 The cdrom_id program is replaced by an advanced version, which can
706 detect most common device types, and also properties of the inserted
707 media. This is part of moving some basic functionality from HAL into
708 udev (and the kernel).
714 The last WAIT_FOR_SYSFS rule is removed from the default rules.
716 The symlinks to udevadm for the debugging tools: udevmonitor and
717 udevtest are no longer created.
719 The symlinks to the udevadm man page for the old tool names are
722 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
723 should be prefixed with '@' to indicate that the path is not a
734 Udevstart is removed from the tree, it did not get installed for
735 a long time now, and is long replaced by trigger and settle.
741 All udev tools are merged into a single binary called udevadm.
742 The old names of the tools are built-in commands in udevadm now.
743 Symlinks to udevadm, with the names of the old tools, provide
744 the same functionality as the standalone tools. There is also
745 only a single udevadm.8 man page left for all tools.
747 Tools like mkinitramfs should be checked, if they need to include
748 udevadm in the list of files.
758 The etc/udev/rules.d/ directory now contains a default set of basic
759 udev rules. This initial version is the result of a rules file merge
760 of Fedora and openSUSE. For these both distros only a few specific
761 rules are left in their own file, named after the distro. Rules which
762 are optionally installed, because they are only valid for a specific
763 architecture, or rules for subsystems which are not always used are
764 in etc/udev/packages/.
770 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
771 actions by dynamically created rules.
773 SYMLINK=="<value>" matches agains the entries in the list of
774 currently defined symlinks. The links are not created in the
775 filesystem at that point in time, but the values can be matched.
777 RUN{ignore_error}+="<program>" will ignore any exit code from the
778 program and not record as a failed event.
784 Final merge of patches/features from the Ubuntu package.
790 Control characters in filesystem label strings are no longer silenty
791 removed, but hex-encoded, to be able to uniquely identify the device
792 by its symlink in /dev/disk/by-label/.
793 If libvolume_id is used by mount(8), LABEL= will work as expected,
794 if slashes or other characters are used in the label string.
796 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
797 can be specified now. The TEST key accepts an optional mode mask
798 TEST{0100}=="<is executable file>".
800 Scsi_id now supports a mode without expecting scsi-specific sysfs
801 entries to allow the extraction of cciss-device persistent properties.
807 In the future, we may see uuid's which are just simple character
808 strings (see the DDF Raid Specification). For that reason vol_id now
809 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
810 the creation of symlinks, the *_SAFE values ensure, that no control
811 or whitespace characters are used in the filename.
813 Possible users of libvolume_id, please use the volume_id_get_* functions.
814 The public struct will go away in a future release of the library.
820 Removal of useless extras/eventrecorder.sh.
830 The directory multiplexer for dev.d/ and hotplug.d are finally removed
831 from the udev package.
837 Symlinks can have priorities now, the priority is assigned to the device
838 and specified with OPTIONS="link_priority=100". Devices with higher
839 priorities overwrite the symlinks of devices with lower priorities.
840 If the device that currently owns the link, goes away, the symlink
841 will be removed, and recreated, pointing to the next device with the
842 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
843 more reliable, if multiple devices contain the same metadata and overwrite
846 The dasd_id program is removed from the udev tree, and dasdinfo, with the
847 needed rules, are part of the s390-tools now.
849 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
850 we may get the scsi sysfs mess fixed some day, and this will only catch
851 the devices we are looking for.
853 USB serial numbers for storage devices have the target:lun now appended,
854 to make it possibble to distinguish broken multi-lun devices with all
855 the same SCSI identifiers.
857 Note: The extra "run_directory" which searches and executes stuff in
858 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
859 with the next release. Make sure, that you don't use it anymore, or
860 provides your own implementation of that inefficient stuff.
861 We are tired of reports about a "slow udev", because these directories
862 contain stuff, that runs with _every_ event, instead of using rules,
863 that run programs only for the matching events.
873 DRIVER== will match only for devices that actually have a real
874 driver. DRIVERS== must be used, if parent devices should be
875 included in the match.
877 Libvolume_id's "linux_raid" detection needed another fix.
885 Add additional check to volume_id detection of via_raid, cause
886 some company decided to put a matching pattern all over the empty
887 storage area of their music players.
891 Fix path_id for SAS devices.
895 The udev daemon can be started with --debug-trace now, which will
896 execute all events serialized to get a chance to catch a possible
897 action that crashes the box.
899 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
900 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
901 are excluded from the warning. Referencing parent attributes directly
902 may break when something in the kernel driver model changes. Udev will
903 just find the attribute by walking up the parent chain.
905 Udevtrigger now sorts the list of devices depending on the device
906 dependency, so a "usb" device is triggered after the parent "pci"
911 Revert persistent-storage ata-serial '_' '-' replacement.
917 Udevtrigger can now filter the list of devices to be triggered. Matches
918 for subsystems or sysfs attributes can be specified.
920 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
921 zero-sized files to avoid pointing to /sys and confuse broken tools which
922 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
925 The rules and scripts to create udev rules for persistent network
926 devices and optical drives are in the extras/rules_generator directory
927 now. If you use something similar, please consider replacing your own
928 version with this, to share the support effort. The rule_generator
929 installs its own rules into /etc/udev/rules.d.
931 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
932 the rule_generator depends on cdrom_id to be called in an earlier rule.
938 Renaming of some key names (the old names still work):
939 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
940 (The behavior of the key DRIVER will change soon in one of the next
941 releases, to match only the event device, please switch to DRIVERS
942 instead. If DRIVER is used, it will behave like DRIVERS, but an error
944 With the new key names, we have a more consistent and simpler scheme.
945 We can match the properties of the event device only, with: KERNEL,
946 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
947 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
948 longer mentioned in the man page and should be switched in the rule
951 ATTR{file}="value" can be used now, to write to a sysfs file of the
952 event device. Instead of:
953 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
955 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
957 All the PHYSDEV* keys are deprecated and will be removed from a
959 PHYDEVPATH - is the path of a parent device and should not be
961 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
962 matched with SUBSYSTEMS==
963 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
964 Newer kernels will have DRIVER in the environment,
965 for older kernels udev puts in. Class device will
966 no longer carry this property of a parent and
967 DRIVERS== can be used to match such a parent value.
968 Note that ENV{DRIVER} is only available for a few bus devices, where
969 the driver is already bound at device event time. On coldplug, the
970 events for a lot devices are already bound to a driver, and they will have
971 that value set. But on hotplug, at the time the kernel creates the device,
972 it can't know what driver may claim the device after that, therefore
973 in most cases it will be empty.
975 Failed events should now be re-triggered with:
976 udevtrigger --retry-failed.
977 Please switch to this command, so we keep the details of the /dev/.udev/failed/
978 files private to the udev tools. We may need to switch the current symlink
979 target, cause some obviously broken tools try to scan all files in /dev
980 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
981 million times. This takes ages on slow boxes.
983 The udevinfo attribute walk (-a) now works with giving a device node
984 name (-n) instead of a devpath (-p). The query now always works, also when
985 no database file was created by udev.
987 The built-in /etc/passwd /etc/group parser is removed, we always depend on
988 getpwnam() and getgrnam() now. One of the next releases will depend on
989 fnmatch() and may use getopt_long().
993 Bugfixes and small improvements.
997 Fix path_id for recent kernels.
1003 Added support for swapping network interface names, by temporarily
1004 renaming the device and wait for the target name to become free.
1008 The built-in MODALIAS key and substitution is removed.
1012 The binary firmware helper is replaced by the usual simple
1013 shell script. Udevsend is removed from the tree.
1021 Some more keys require the correct use of '==' and '=' depending
1022 on the kind of operation beeing an assignment or a match. Rules
1023 with invalid operations are skipped and logged to syslog. Please
1024 test with udevtest if the parsing of your rules throws errors and
1025 fix possibly broken rules.
1029 Provide "udevsettle" to wait for all current udev events to finish.
1030 It also watches the current kernel netlink queue by comparing the
1031 even sequence number to make sure that there are no current pending
1032 events that have not already arrived in the daemon.
1036 Fix rule to skip persistent rules for removable IDE devices, which
1037 also skipped optical IDE drives.
1039 All *_id program are installed in /lib/udev/ by default now.
1041 No binary is stripped anymore as this should be done in the
1042 packaging process and not at build time.
1044 libvolume_id is provided as a shared library now and vol_id is
1045 linked against it. Also one of the next HAL versions will require
1046 this library, and the HAL build process will also require the
1047 header file to be installed. The copy of the same code in HAL will
1048 be removed to have only a single copy left on the system.
1052 Add persistent links for SCSI tapes. The rules file is renamed
1053 to 60-persistent-storage.rules.
1055 Create persistent path for usb devices. Can be used for all sorts
1056 of devices that can't be distinguished by other properties like
1057 multiple identical keyboards and mice connected to the same box.
1059 Provide "udevtrigger" program to request events on coldplug. The
1060 shell script is much too slow with thousends of devices.
1064 Fix persistent disk rules to exclude removable IDE drives.
1066 Warn if %e, $modalias or MODALIAS is used.
1070 Fix queue export, which wasn't correct for subsequent add/remove
1071 events for the same device.
1075 Fix cramfs detection on big endian.
1077 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
1082 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
1083 attributes were only checked at the parent device that matched the
1084 by BUS requested subsystem. Fix it to also look at the device we
1085 received the event for.
1087 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
1092 Fix a bug where NAME="" would prevent RUN from beeing executed.
1094 RUN="/bin/program" does not longer automatically add the subsystem
1095 as the first parameter. This is from the days of /sbin/hotplug
1096 which is dead now and it's just confusing to need to add a space at
1097 the end of the program name to prevent this.
1098 If you use rules that need the subsystem as the first parameter,
1099 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
1100 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
1104 The udev man page has moved to udev(7) as it does not describe a command
1105 anymore. The programs udev, udevstart and udevsend are no longer installed
1106 by default and must be copied manually, if they should be installed or
1107 included in a package.
1109 Fix a bug where "ignore_device" could run earlier collected RUN keys before
1110 the ignore rule was applied.
1112 More preparation for future sysfs changes. usb_id and scsi_id no longer
1113 depend on a magic order of devices in the /devices chain. Specific devices
1114 should be requested by their subsytem.
1116 This will always find the scsi parent device without depending on a specific
1118 dev = sysfs_device_get(devpath);
1119 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
1121 The "device" link in the current sysfs layout will be automatically
1122 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
1123 parent in the devpath. If a device is requested by it's symlink, like all
1124 class devices in the new sysfs layout will look like, it gets automatically
1125 resolved and substituted with the real devpath and not the symlink path.
1128 A similar logic must be applied to _all_ sysfs users, including
1129 scripts, that search along parent devices in sysfs. The explicit use of
1130 the "device" link must be avoided. With the future sysfs layout all
1131 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
1132 back to the "class" or the "bus". The layout of the parent devices in
1133 /devices is not necessarily expected to be stable across kernel releases and
1134 searching for parents by their subsystem should make sysfs users tolerant
1135 for changed parent chains.
1139 Prepare udev to work with the experimental kernel patch, that moves
1140 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
1142 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
1143 moving the class devices to /sys/devices.
1145 Thanks again to Marco for help finding a hopefully nice compromise
1146 to make %b simpler and working again.
1150 Complete removal of libsysfs, replaced by simple helper functions
1151 which are much simpler and a bit faster. The udev daemon operatesentirely
1152 on event parameters and does not use sysfs for simple rules anymore.
1153 Please report any new bugs/problems, that may be caused by this big
1154 change. They will be fixed immediately.
1156 The enumeration format character '%e' is deprecated and will be
1157 removed sometimes from a future udev version. It never worked correctly
1158 outside of udevstart, so we can't use it with the new parallel
1159 coldplug. A simple enumeration is as useless as the devfs naming
1160 scheme, just get rid of both if you still use it.
1162 MODALIAS and $modalias is not needed and will be removed from one of
1163 the next udev versions, replace it in all rules with ENV{MODALIAS} or
1164 the sysfs "modalias" value.
1166 Thanks a lot to Marco for all his help on finding and fixing bugs.
1170 Let scsi_id request libata drive serial numbers from page 0x80.
1172 Renamed etc/udev/persistent.rules to persistent-disk.rules and
1173 added /dev/disk/by-name/* for device mapper device names.
1175 Removed %e from the man page. It never worked reliably outside
1176 of udevstart and udevstart is no longer recommended to use.
1180 Symlinks are now exported to the event environment. Hopefully it's no
1181 longer needed to run udevinfo from an event process, like it was
1182 mentioned on the hotplug list:
1183 UDEV [1134776873.702967] add@/block/sdb
1186 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
1190 Fix a problem if udevsend is used as the hotplug handler and tries to use
1191 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
1192 and this kind of problems will hopefully go away soon.
1196 All built-in logic to work around bad sysfs timing is removed with this
1197 version. The need to wait for sysfs files is almost fixed with a kernel
1198 version that doesn't work with this udev version anyway. Until we fix
1199 the timing of the "bus" link creation, the former integrated logic should
1200 be emulated by a rule placed before all other rules:
1201 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
1203 The option "udev_db" does no longer exist. All udev state will be in
1204 /$udev_root/.udev/ now, there is no longer an option to set this
1206 If the init script or something else used this value, just depend on
1207 this hardcoded path. But remember _all_content_ of this directory is
1208 still private to udev and can change at any time.
1210 Default location for rule sripts and helper programs is now: /lib/udev/.
1211 Everything that is not useful on the commandline should go into this
1212 directory. Some of the helpers in the extras folder are installed there
1213 now. The rules need to be changed, to find the helpers there.
1215 Also /lib/udev/devices is recommended as a directory where packages or
1216 the user can place real device nodes, which get copied over to /dev at
1217 every boot. This should replace the various solutions with custom config
1220 Udevsend does no longer start the udev daemon. This must be done with
1221 the init script that prepares /dev on tmpfs and creates the initial nodes,
1222 before starting the daemon.
1226 Silent a too verbose error logging for the old hotplug.d/ dev.d/
1229 The copy of klibc is removed. A systemwide installed version of klibc
1230 should be used to build a klibc udev now.
1234 NAME="" will not create any nodes, but execute RUN keys. To completely
1235 ignore an event the OPTION "ignore_device" should be used.
1237 After removal of the reorder queue, events with a TIMEOUT can be executed
1238 without any queuing now.
1242 Fixed bug in udevd, if inotify is not available. We depend on netlink
1243 uevents now, kernels without that event source will not work with that
1244 version of udev anymore.
1248 The rule parsing happens now in the daemon once at startup, all udev
1249 event processes inherit the already parsed rules from the daemon.
1250 It is shipped with SUSE10.0 and reduces heavily the system load at
1251 startup. The option to save precompiled rules and let the udev process
1252 pick the them up is removed, as it's no longer needed.
1254 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
1255 device. Libsysfs is changed to "translate" the requested link into the
1256 real device path, as it would happen with the hotplug event. Otherwise
1257 device removal and the udev database will not work.
1259 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
1262 A few improvements for vol_id, the filesytem probing code.
1266 Fix a stupid typo in extras/run_directory for "make install".
1268 scsi_id creates the temporary devnode now in /dev for usage with a
1269 non-writable /tmp directory.
1271 The uevent kernel socket buffer can carry app. 50.000 events now,
1272 let's see who can break this again. :)
1274 The upcoming kernel will have a new input driver core integration.
1275 Some class devices are now symlinks to the real device. libsysfs
1276 needs a fix for this to work correctly. Udevstart of older udev
1277 versions will _not_ create these devices!
1281 Fix a 'install' target in the Makefile, that prevents EXTRAS from
1286 A bunch of mostly trivial bugfixes. From now on no node name or
1287 symlink name can contain any character than plain whitelisted ascii
1288 characters or validated utf8 byte-streams. This is needed for the
1289 /dev/disk/by-label/* links, because we import untrusted data and
1290 export it to the filesystem.
1294 More bugfixes. If udevd was started from the kernel, we don't
1295 have stdin/stdout/stderr, which broke the forked tools in some
1300 Bugfix. udevstart event ordering was broken for a long time.
1301 The new run_program() uncovered it, because /dev/null was not
1302 available while we try to run external programs.
1303 Now udevstart should create it before we run anything.
1307 Minor bugfixes and some distro rules updates. If you don't have the
1308 persistent disk rules in /dev/disk/by-*/* on your distro, just
1309 grab it from here. :)
1313 We can use socket communication now to pass events from udev to
1315 RUN+="socket:/org/freedesktop/hal/udev_event"
1316 will pass the whole udev event to the HAL daemon without the need
1317 for a forked helper. (See ChangeLog for udevmonitor, as an example)
1321 Mostly bugfixes and see ChangeLog.
1323 The test for the existence of an environment value should be
1325 ENV{KEY}=="*" to ENV{KEY}=="?*"
1326 because "*" will not fail anymore, if the key does not exist or
1331 Bugfixes and a few tweaks described in the ChangeLog.
1335 Mostly a Bugfix release.
1337 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
1338 timing with custom rules.
1342 We changed the internal rule storage format. Our large rule files took
1343 2 MB of RAM, with the change we are down to 99kB.
1345 If the device-node has been created with default name and no symlink or
1346 options are to remenber, it is not longer stored in the udevdb. HAL will
1347 need to be updated to work correctly with that change.
1349 To overrride optimization flags, OPTFLAGS may be used now.
1357 Major changes happened with this release. The goal is to take over the
1358 complete kernel-event handling and provide a more efficient way to dispatch
1359 kernel events. Replacing most of the current shell script logic and the
1360 kernel forked helper with a netlink-daemon and a rule-based event handling.
1362 o udevd listens to netlink events now. The first valid netlink event
1363 will make udevd ignore any message from udevsend that contains a
1364 SEQNUM, to avoid duplicate events. The forked events can be disabled
1366 echo "" > /proc/sys/kernel/hotplug
1367 For full support, the broken input-subsytem needs to be fixed, not to
1368 bypass the driver core.
1370 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
1371 removed from udev itself and must be emulated by calling small
1372 helper binaries provided in the extras folder:
1373 make EXTRAS=extras/run_directory/
1374 will build udev_run_devd and udev_run_hotplugd, which can be called
1375 from a rule if needed:
1376 RUN+="/sbin/udev_run_hotplugd"
1377 The recommended way to handle this is to convert all the calls from
1378 the directories to explicit udev rules and get completely rid of the
1379 multiplexing. (To catch a ttyUSB event, you now no longer need to
1380 fork and exit 300 tty script instances you are not interested in, it
1381 is just one rule that matches exactly the device.)
1383 o udev handles now _all_ events not just events for class and block
1384 devices, this way it is possible to control the complete event
1385 behavior with udev rules. Especially useful for rules like:
1386 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
1388 o As used in the modalias rule, udev supports now textual
1389 substitution placeholder along with the usual format chars. This
1390 needs to be documented, for now it's only visible in udev_rules_parse.c.
1392 o The rule keys support now more operations. This is documented in the
1393 man page. It is possible to add values to list-keys like the SYMLINK
1394 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
1395 Also "final"-assignments are supported by using KEY:="value", which will
1396 prevent changing the key by any later rule.
1398 o kernel 2.6.12 has the "detached_state" attribute removed from
1399 sysfs, which was used to recognize sysfs population. We switched that
1400 to wait for the "bus" link, which is only available in kernels after 2.6.11.
1401 Running this udev version on older kernels may cause a short delay for
1404 o To provide infrastructure for persistent device naming, the id programs:
1405 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
1406 to export the probed data in environment key format:
1407 pim:~ # /sbin/ata_id --export /dev/hda
1408 ID_MODEL=HTS726060M9AT00
1409 ID_SERIAL=MRH401M4G6UM9B
1410 ID_REVISION=MH4OA6BA
1412 The following rules:
1413 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
1414 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
1417 kay@pim:~> tree /dev/disk
1420 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
1421 | `-- IBM-Memory_Key -> ../../sda
1423 | |-- swap -> ../../hda1
1424 | |-- date -> ../../sda1
1425 | `-- home -> ../../hda3
1427 |-- 2E08712B0870F2E7 -> ../../hda3
1428 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
1429 |-- E845-7A89 -> ../../sda1
1430 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
1432 The IMPORT= operation will import these keys in the environment and make
1433 it available for later PROGRAM= and RUN= executed programs. The keys are
1434 also stored in the udevdb and can be queried from there with one of the
1437 o A few binaries are silently added to the repository, which can be used
1438 to replay kernel events from initramfs instead of using coldplug. udevd
1439 can be instructed now to queue-up events while the stored events from
1440 initramfs are filled into the udevd-queue. This code is still under
1441 development and there is no documentation now besides the code itself.
1442 The additional binaries get compiled, but are not installed by default.
1444 o There is also a temporary fix for a performance problem where too many
1445 events happen in parallel and every event needs to parse the rules.
1446 udev can now read precompiled rules stored on disk. This is likely to be
1447 replaced by a more elegant solution in a future udev version.
1451 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
1452 Fix for libsysfs not to expect this file was added.
1456 All rules are applied now, but only the first matching rule with a NAME-key
1457 will be applied. All later rules with NAME-key are completely ignored. This
1458 way system supplied symlinks or permissions gets applied to user-defined
1462 Please check your rules setup, if you may need to add OPTIONS="last_rule"
1463 to some rules, to keep the old behavior.
1465 The rules are read on "remove"-events too. That makes is possible to match
1466 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
1467 instruct udev to ignore an event (OPTIONS="ignore_device").
1468 The new ACTION-key may be used to let a rule act only at a "remove"-event.
1470 The new RUN-key supports rule-based execution of programs after device-node
1471 handling. This is meant as a general replacement for the dev.d/-directories
1472 to give fine grained control over the execution of programs.
1474 The %s{}-sysfs format char replacement values are searched at any of the
1475 devices in the device chain now, not only at the class-device.
1477 We support log priority levels now. The value udev_log in udev.conf is used
1478 to determine what is printed to syslog. This makes it possible to
1479 run a version with compiled-in debug messages in a production environment
1480 which is sometimes needed to find a bug.
1481 It is still possible to supress the inclusion of _any_ syslog usage with
1482 USE_LOG=false to create the smallest possible binaries if needed.
1483 The configured udev_log value can be overridden with the environment variable
1488 Possible use of a system-wide klibc:
1489 make USE_KLIBC=true KLCC=/usr/bin/klcc all
1490 will link against an external klibc and our own version will be ignored.
1494 We support an unlimited count of symlinks now.
1496 If USE_STATIC=true is passed to a glibc build, we link statically and use
1497 a built-in userdb parser to resolve user and group names.
1499 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
1500 we walk up the chain of physical devices to find a match.
1502 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
1503 easy to skip certain attribute matches without composing rules with weird
1504 character class negations like:
1505 KERNEL="[!s][!c][!d]*"
1506 this can now be replaced with:
1508 The current simple '=' is still supported, and should work as it does today,
1509 but existing rules should be converted if possible, to be better readable.
1511 We have new ENV{}== key now, to match against a maximum of 5 environment
1514 udevstart is its own binary again, because we don't need co carry this araound
1515 with every forked event.