5 warning if /run is not writable.
9 udevadm info --cleanup-db
15 The udev runtime data moved from /dev/.udev/ to /run/udev/. The
16 /run mountpoint is supposed to be a tmpfs mounted during early boot,
17 available and writable to for all tools at any time during bootup,
18 it replaces /var/run/, which should become a symlink some day.
20 If /run does not exist, or is not writable, udev will fall back using
23 On systemd systems with initramfs and LVM used, packagers must
24 make sure, that the systemd and initramfs versions match. The initramfs
25 needs to create the /run mountpoint for udev to store the data, and
26 mount this tmpfs to /run in the rootfs, so the that the udev database
27 is preserved for the udev version started in the rootfs.
29 The command 'udevadm info --convert-db' is gone. The udev daemon
30 itself, at startup, converts any old database version if necessary.
32 The systemd services files have been reorganized. The udev control
33 socket is bound by systemd and passed to the started udev daemon.
34 The udev-settle.service is no longer active by default. Services which
35 can not handle hotplug setups properly need to actively pull it in, to
36 act like a barrier. Alternatively the settle service can be unconditionally
37 'systemctl'enabled, and act like a barrier for basic.target.
39 The fstab_import callout is no longer built or installed. Udev
40 should not be used to mount, does not watch changes to fstab, and
41 should not mirror fstab values in the udev database.
47 New and updated keymaps.
53 The udev database has changed, After installation of a new udev
54 version, 'udevadm info --convert-db' should be called, to let the new
55 udev/libudev version read the already stored data.
57 udevadm now supports quoting of property values, and prefixing of
59 $ udevadm info --export --export-prefix=MY_ --query=property -n sda
67 udev_device_get_is_initialized()
68 udev_enumerate_add_match_is_initialized()
69 to be able to skip devices the kernel has created , but udev has
73 udev_device_get_usec_since_initialized()
74 to retrieve the "age" of a udev device record.
76 GUdev supports a more generic GUdevEnumerator class, udev TAG
77 handling, device initialization and timestamp now.
79 The counterpart of /sys/dev/{char,block}/$major:$minor,
80 /dev/{char,block}/$major:$minor symlinks are now unconditionally
81 created, even when no rule files exist.
83 New and updated keymaps.
89 GUdev moved from /usr to /.
99 Persistent network naming rules are disabled inside of Qemu/KVM now.
101 New and updated keymaps.
103 Udev gets unconditionally enabled on systemd installations now. There
104 is no longer the need to to run 'systemctl enable udev.service'.
118 New and fixed keymaps.
120 Install systemd service files if applicable.
126 All distribution specific rules are removed from the udev source tree,
127 most of them are no longer needed. The Gentoo rules which allow to support
128 older kernel versions, which are not covered by the default rules anymore
129 has moved to rules/misc/30-kernel-compat.rules.
135 The option --debug-trace and the environemnt variable UDEVD_MAX_CHILDS=
136 was removed from udevd.
138 Udevd now checks the kernel commandline for the following variables:
139 udev.log-priority=<syslog priority>
140 udev.children-max=<maximum number of workers>
141 udev.exec-delay=<seconds to delay the execution of RUN=>
142 to help debuging coldplug setups where the loading of a kernel
143 module crashes the system.
145 The subdirectory in the source tree rules/packages has been renamed to
146 rules/arch, anc contains only architecture specific rules now.
156 Now the udev daemon itself, does on startup:
157 - copy the content of /lib/udev/devices to /dev
158 - create the standard symlinks like /dev/std{in,out,err},
159 /dev/core, /dev/fd, ...
160 - use static node information provided by kernel modules
161 and creates these nodes to allow module on-demand loading
162 - possibly apply permissions to all ststic nodes from udev
163 rules which are annotated to match a static node
165 The default mode for a device node is 0600 now to match the kernel
166 created devtmpfs defaults. If GROUP= is specified and no MODE= is
167 given the default will be 0660.
173 Udev now gradually starts to pass control over the primary device nodes
174 and their names to the kernel, and will in the end only manage the
175 permissions of the node, and possibly create additional symlinks.
176 As a first step NAME="" will be ignored, and NAME= setings with names
177 other than the kernel provided name will result in a logged warning.
178 Kernels that don't provide device names, or devtmpfs is not used, will
179 still work as they did before, but it is strongly recommended to use
180 only the same names for the primary device node as the recent kernel
181 provides for all devices.
185 Fix broken firmware loader search path.
191 "udevadm trigger" defaults to "change" events now instead of "add"
192 events. The "udev boot script" might need to add "--action=add" to
193 the trigger command if not already there, in case the initial coldplug
194 events are expected as "add" events.
196 The option "all_partitons" was removed from udev. This should not be
197 needed for usual hardware. Udev can not safely make assumptions
198 about non-existing partition major/minor numbers, and therefore no
199 longer provide this unreliable and unsafe option.
201 The option "ignore_remove" was removed from udev. With devtmpfs
202 udev passed control over device nodes to the kernel. This option
203 should not be needed, or can not work as advertised. Neither
204 udev nor the kernel will remove device nodes which are copied from
205 the /lib/udev/devices/ directory.
207 All "add|change" matches are replaced by "!remove" in the rules and
208 in the udev logic. All types of events will update possible symlinks
209 and permissions, only "remove" is handled special now.
211 The modem modeswitch extra was removed and the external usb_modeswitch
212 program should be used instead.
214 New and fixed keymaps.
224 Kernels with SYSFS_DEPRECATED=y are not supported since a while. Many users
225 depend on the current sysfs layout and the information not available in the
226 deprecated layout. All remaining support for the deprecated sysfs layout is
231 Fix for a possible endless loop in the new input_id program.
237 The option "ignore_device" does no longer exist. There is no way to
238 ignore an event, as libudev events can not be suppressed by rules.
239 It only prevented RUN keys from being executed, which results in an
240 inconsistent behavior in current setups.
242 BUS=, SYSFS{}=, ID= are long deprecated and should be SUBSYSTEM(S)=,
243 ATTR(S){}=, KERNEL(S)=. It will cause a warning once for every rule
246 The support for the deprecated IDE devices has been removed from the
247 default set of rules. Distros who still care about non-libata drivers
248 need to add the rules to the compat rules file.
250 The ID_CLASS property on input devices has been replaced by the more accurate
251 set of flags ID_INPUT_{KEYBOARD,KEY,MOUSE,TOUCHPAD,TABLET,JOYSTICK}. These are
252 determined by the new "input_id" prober now. Some devices, such as touchpads,
253 can have several classes. So if you previously had custom udev rules which e. g.
254 checked for ENV{ID_CLASS}=="kbd", you need to replace this with
255 ENV{ID_INPUT_KEYBOARD}=="?*".
261 To support DEVPATH strings larger than the maximum file name length, the
262 private udev database format has changed. If some software still reads the
263 private files in /dev/.udev/, which it shouldn't, now it's time to fix it.
264 Please do not port anything to the new format again, everything in /dev/.udev
265 is and always was private to udev, and may and will change any time without
268 Multiple devices claiming the same names in /dev are limited to symlinks
269 only now. Mixing identical symlink names and node names is not supported.
270 This reduces the amount of data in the database significantly.
272 NAME="%k" causes a warning now. It's is and always was completely superfluous.
273 It will break kernel supplied DEVNAMEs and therefore it needs to be removed
276 Most NAME= instructions got removed. Kernel 2.6.31 supplies the needed names
277 if they are not the default. To support older kernels, the NAME= rules need to
278 be added to the compat rules file.
280 Symlinks to udevadm with the old command names are no longer resolved to
281 the udevadm commands.
283 The udev-acl tool got adopted to changes in ConsoleKit. Version 0.4.1 is
286 The option "last_rule" does no longer exist. Its use breaks too many
287 things which expect to be run from independent later rules, and is an idication
288 that something needs to be fixed properly instead.
290 The gudev API is no longer marked as experimental,
291 G_UDEV_API_IS_SUBJECT_TO_CHANGE is no longer needed. The gudev introspection
292 is enabled by default now. Various projects already depend on introspection
293 information to bind dynamic languages to the gudev interfaces.
299 The udevadm trigger "--retry-failed" option, which is replaced since quite
300 a while by "--type=failed" is removed.
302 The failed tracking was not working at all for a few releases. The RUN
303 option "ignore_error" is replaced by a "fail_event_on_error" option, and the
304 default is not to track any failing RUN executions.
306 New keymaps, new modem, hid2hci updated.
310 Fix possible crash in udevd when worker processes are busy, rules are
311 changed at the same time, and workers get killed to reload the rules.
317 Properties set with ENV{.FOO}="bar" are marked private by starting the
318 name with a '.'. They will not be stored in the database, and not be
319 exported with the event.
321 Firmware files are looked up in:
322 /lib/firmware/updates/$(uname -r)
323 /lib/firmware/updates
324 /lib/firmware/$(uname -r)
328 ATA devices switched the property from ID_BUS=scsi to ID_BUS=ata.
329 ata_id, instead of scsi_id, is the default tool now for ATA devices.
335 The configure options have changed because another library needs to be
336 installed in a different location. Instead of exec_prefix and udev_prefix,
337 libdir, rootlibdir and libexecdir are used. The Details are explained in
340 Event processes now get re-used after they handled an event. This reduces
341 the number of forks and the pressure on the CPU significantly, because
342 cloned event processes no longer cause page faults in the main daemon.
343 After the events have settled, a few worker processes stay around for
344 future events, all others get cleaned up.
346 To be able to use signalfd(), udev depends on kernel version 2.6.25 now.
347 Also inotify support is mandatory now to run udev.
349 The format of the queue exported by the udev damon has changed. There is
350 no longer a /dev/.udev/queue/ directory. The current event queue can be
351 accessed with udevadm settle and libudedv.
353 Libudev does not have the unstable API header anymore. From now on,
354 incompatible changes will be handled by bumping the library major version.
356 To build udev from the git tree gtk-doc is needed now. The tarballs will
357 build without it and contain the pre-built documentation. An online copy
359 http://www.kernel.org/pub/linux/utils/kernel/hotplug/libudev/
361 The tools from the udev-extras repository have been merged into the main
362 udev repository. Some of the extras have larger external dependencies, and
363 they can be disabled with the configure switch --disable-extras.
369 The program vol_id and the library libvolume_id are removed from the
370 repository. Libvolume_id is merged with libblkid from the util-linux-ng
371 package. Persistent disk links for label and uuid depend on the
372 util-linux-ng version (2.15) of blkid now. Older versions of blkid
373 can not be used with udev.
375 Libudev allows to subscribe to udev events. To prevent unwanted messages
376 to be delivered, and waking up the subscribing process, a filter can be
377 installed, to drop messages inside a kernel socket filter. The filters
378 match on the <subsytem>:<devtype> properties of the device.
379 This is part of the ongoing effort to replace HAL, and switch current
380 users over to directly use libudev.
381 Libudev is still marked as experimental, and its interface might
382 eventually change if needed, but no major changes of the currently exported
383 interface are expected anymore, and a first stable release should happen
386 A too old kernel (2.6.21) or a kernel with CONFIG_SYSFS_DEPRECATED
387 is not supported since while and udevd will log an error message at
388 startup. It should still be able to boot-up, but advanced rules and system
389 services which depend on the information not available in the old sysfs
390 format will fail to work correctly.
392 DVB device naming is supplied by the kernel now. In case older kernels
393 need to be supported, the old shell script should be added to a compat
400 The processed udev events get send back to the netlink socket. Libudev
401 provides access to these events. This is work-in-progress, to replace
402 the DeviceKit daemon functionality directly with libudev. There are
403 upcoming kernel changes to allow non-root users to subcribe to these
410 "udevadm settle" now optionally accepts a range of events to wait for,
411 instead of waiting for "all" events.
417 The installed watch for block device metadata changes is now removed
418 during event hadling, because some (broken) tools may be called from udev
419 rules and (wrongly) open the device with write access. After the finished
420 event handling the watch is restored.
426 Device nodes can be watched for changes with inotify with OPTIONS="watch".
427 If closed after being opened for writing, a "change" uevent will occur.
428 /dev/disk/by-{label,uuid}/* symlinks will be automatically updated.
434 The udevadm test command has no longer a --force option, nodes and symlinks
435 are always updated with a test run now.
437 The udevd daemon can be started with --resolve-names=never to avoid all user
438 and group lookups (e.g. in cut-down systems) or --resolve-names=late to
439 lookup user and groups every time events are handled.
445 We are currently merging the Ubuntu rules in the udev default rules,
446 and get one step closer to provide a common Linux /dev setup, regarding
447 device names, symlinks, and default device permissions. On udev startup,
448 we now expect the following groups to be resolvable to their ids with
450 disk, cdrom, floppy, tape, audio, video, lp, tty, dialout, kmem.
451 LDAP setups need to make sure, that these groups are always resolvable at
452 bootup, with only the rootfs mounted, and without network access available.
454 Some systems may need to add some new, currently not used groups, or need
455 to add some users to new groups, but the cost of this change is minimal,
456 compared to the pain the current, rather random, differences between the
457 various distributions cause for upstream projects and third-party vendors.
459 In general, "normal" users who log into a machine should never be a member
460 of any such group, but the device-access should be managed by dynamic ACLs,
461 which get added and removed for the specific users on login/logout and
462 session activity/inactivity. These groups are only provided for custom setups,
463 and mainly system services, to allow proper privilege separation.
464 A video-streaming daemon uid would be a member of "audio" and "video", to get
465 access to the sound and video devices, but no "normal" user should ever belong
466 to the "audio" group, because he could listen to the built-in microphone with
467 any ssh-session established from the other side of the world.
469 /dev/serial/by-{id,path}/ now contains links for ttyUSB devices,
470 which do not depend on the kernel device name. As usual, unique
471 devices - only a single one per product connected, or a real
472 USB serial number in the device - are always found with the same
473 name in the by-id/ directory.
474 Completely identical devices may overwrite their names in by-id/
475 and can only be found reliably in the by-path/ directory. Devices
476 specified by by-path/ must not change their connection, like the
477 USB port number they are plugged in, to keep their name.
479 To support some advanced features, Linux 2.6.22 is the oldest supported
480 version now. The kernel config with enabled SYSFS_DEPRECATED is no longer
481 supported. Older kernels should still work, and devices nodes should be
482 reliably created, but some rules and libudev will not work correctly because
483 the old kernels do not provide the expected information or interfaces.
489 Fix for a possible segfault while swapping network interface names in udev
496 The group "video" is part of the default rules now.
500 Bugfix for kernels using SYSFS_DEPRECATED* option and finding parent
501 block devices in some cases. No common distro uses this option anymore,
502 and we do not get enough testing for this and recent udev versions. If
503 this option is not needed to run some old distro with a new kernel,
504 it should be disabled in the kernel config.
506 Bugfix for the $links substitution variable, which may crash if no links
507 are created. This should not happen in usual setups because we always
508 create /dev/{block,char}/ links.
510 The strings of the parsed rules, which are kept in memory, no longer
511 contain duplicate entries, or duplicate tails of strings. This, and the
512 new rules parsing/matching code reduces the total in-memory size of
513 a huge distro rule sets to 0.08 MB, compared to the 1.2MB of udev
516 The export of DEVTYPE=disk/partition got removed from the default
517 rules. This value is available from the kernel. The pnp shell script
518 modprobe hack is removed from the default rules. ACPI devices have _proper_
519 modalias support and take care of the same functionality.
520 Installations which support old kernels, but install current default
521 udev rules may want to add that to the compat rules file.
523 Libvolume_id now always probes for all known filesystems, and does not
524 stop at the first match. Some filesystems are marked as "exclusive probe",
525 and if any other filesytem type matches at the same time, libvolume_id
526 will, by default, not return any probing result. This is intended to prevent
527 mis-detection with conflicting left-over signatures found from earlier
528 file system formats. That way, we no longer depend on the probe-order
529 in case of multiple competing signatures. In some setups the kernel allows
530 to mount a volume with just the old filesystem signature still in place.
531 This may damage the new filesystem and cause data-loss, just by mounting
532 it. Because volume_id can not decide which one the correct signature is,
533 the wrong signatures need to be removed manually from the volume, or the
534 volume needs to be reformatted, to enable filesystem detection and possible
539 Fix segfault if compiled without optimization and dbg() does not get
540 compiled out and uses variables which are not available.
544 Bugfixes. (And maybe new bugs. :))
546 The rule matching engine got converted from a rule list to a token
547 array which reduced the in-memory rules representation of a full
548 featured distros with thousends of udev rules from 1.2MB to 0.12 MB.
549 Limits like 5 ENV and ATTR matches, and one single instance for most
550 other keys per rule are gone.
552 The NAME assignment is no longer special cased. If later rules assign
553 a NAME value again, the former value will be overwritten. As usual
554 for most other keys, the NAME value can be protected by doing a final
555 assignment with NAME:="<value>".
557 All udev code now uses libudev, which is also exported. The library
558 is still under development, marked as experimental, and its interface
559 may change as long as the DeviceKit integration is not finished.
561 Many thanks to Alan Jenkins for his continuous help, and finding and
562 optimizing some of the computing expensive parts.
568 Kernel devices and device nodes are connected now by reverse indizes in
569 /sys and /dev. A device number retrieved by a stat() or similar, the
570 kernel device directory can be found by looking up:
571 /sys/dev/{block,char}/<maj>:<min>
572 and the device node of the same device by looking up:
573 /dev/{block,char}/<maj>:<min>
577 Fix recently introduced bug, which caused a compilation without large
578 file support, where vol_id does not recognize raid signatures at the end
581 Firewire disks now create both, by-id/scsi-* and by-id/ieee-* links.
582 Seems some kernel versions prevent the creation of the ieee-* links,
583 so people used the scsi-* link which disappeared now.
585 More libudev work. Almost all udevadm functionality comes from libudev
588 udevadm trigger has a new option --type, which allows to trigger events
589 for "devices", for "subsystems", or "failed" devices. The old option
590 --retry-failed" still works, but is no longer mentioned in the man page.
596 The udevadm info --device-id-of-file= output has changed to use
597 the obvious format. Possible current users should use the --export
598 option which is not affected.
600 The old udev commands symlinks to udevadm are not installed, if
601 these symlinks are used, a warning is printed.
607 Optical drive's media is no longer probed for raid signatures,
608 reading the end of the device causes some devices to malfunction.
609 Also the offset of the last session found is used now to probe
612 The volume_id library got a major version number update to 1,
613 some deprecated functions are removed.
615 A shared library "libudev" gets installed now to provide access
616 to udev device information. DeviceKit, the successor of HAL, will
617 need this library to access the udev database and search sysfs for
619 The library is currently in an experimental state, also the API is
620 expected to change, as long as the DeviceKit integration is not
625 We use ./configure now. See INSTALL for details. Current
628 "/usr" - prefix for man pages, include files
630 "" - the root filesystem, prefix for libs and binaries
634 "lib" - directory name for libraries, not a path name
635 multilib 64bit systems may use "lib64" instead of "lib"
637 compile-in verbose debug messages
639 disable all logging and compile-out all log strings
641 link against SELInux libraries, to set the expected context
644 In the default rules, the group "disk" gets permissions 0660 instead
645 of 0640. One small step closer to unify distro rules. Some day, all
646 distros hopefully end up with the same set of rules.
648 No symlinks to udevadm are installed anymore, if they are still needed,
649 they should be provided by the package.
655 Default udev rules, which are not supposed to be edited by the user, should
656 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
657 the udev package and will be replaced with an update. Udev will pick up rule
659 /lib/udev/rules.d/ - default installed rules
660 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
661 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
662 It does not matter in which directory a rule file lives, all files are sorted
665 To help creating /dev/root, we have now:
666 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
669 In case the current --device-id-of-file is already used, please switch to
670 the --export format version, it saves the output parsing and the old
671 format will be changed to use ':' as a separator, like the format in the
676 Fix cdrom_id to properly recognize blank media.
682 Tape drive id-data is queried from /dev/bsg/* instead of the tape
683 nodes. This avoids rewinding tapes on open().
689 The symlinks udevcontrol and udevtrigger are no longer installed by
692 The scsi_id program does not depend on sysfs anymore. It can speak
693 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
694 data, which should solve some old problems with tape devices, where
695 we better do not open all tape device nodes to identify the device.
701 The cdrom_id program is replaced by an advanced version, which can
702 detect most common device types, and also properties of the inserted
703 media. This is part of moving some basic functionality from HAL into
704 udev (and the kernel).
710 The last WAIT_FOR_SYSFS rule is removed from the default rules.
712 The symlinks to udevadm for the debugging tools: udevmonitor and
713 udevtest are no longer created.
715 The symlinks to the udevadm man page for the old tool names are
718 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
719 should be prefixed with '@' to indicate that the path is not a
730 Udevstart is removed from the tree, it did not get installed for
731 a long time now, and is long replaced by trigger and settle.
737 All udev tools are merged into a single binary called udevadm.
738 The old names of the tools are built-in commands in udevadm now.
739 Symlinks to udevadm, with the names of the old tools, provide
740 the same functionality as the standalone tools. There is also
741 only a single udevadm.8 man page left for all tools.
743 Tools like mkinitramfs should be checked, if they need to include
744 udevadm in the list of files.
754 The etc/udev/rules.d/ directory now contains a default set of basic
755 udev rules. This initial version is the result of a rules file merge
756 of Fedora and openSUSE. For these both distros only a few specific
757 rules are left in their own file, named after the distro. Rules which
758 are optionally installed, because they are only valid for a specific
759 architecture, or rules for subsystems which are not always used are
760 in etc/udev/packages/.
766 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
767 actions by dynamically created rules.
769 SYMLINK=="<value>" matches agains the entries in the list of
770 currently defined symlinks. The links are not created in the
771 filesystem at that point in time, but the values can be matched.
773 RUN{ignore_error}+="<program>" will ignore any exit code from the
774 program and not record as a failed event.
780 Final merge of patches/features from the Ubuntu package.
786 Control characters in filesystem label strings are no longer silenty
787 removed, but hex-encoded, to be able to uniquely identify the device
788 by its symlink in /dev/disk/by-label/.
789 If libvolume_id is used by mount(8), LABEL= will work as expected,
790 if slashes or other characters are used in the label string.
792 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
793 can be specified now. The TEST key accepts an optional mode mask
794 TEST{0100}=="<is executable file>".
796 Scsi_id now supports a mode without expecting scsi-specific sysfs
797 entries to allow the extraction of cciss-device persistent properties.
803 In the future, we may see uuid's which are just simple character
804 strings (see the DDF Raid Specification). For that reason vol_id now
805 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
806 the creation of symlinks, the *_SAFE values ensure, that no control
807 or whitespace characters are used in the filename.
809 Possible users of libvolume_id, please use the volume_id_get_* functions.
810 The public struct will go away in a future release of the library.
816 Removal of useless extras/eventrecorder.sh.
826 The directory multiplexer for dev.d/ and hotplug.d are finally removed
827 from the udev package.
833 Symlinks can have priorities now, the priority is assigned to the device
834 and specified with OPTIONS="link_priority=100". Devices with higher
835 priorities overwrite the symlinks of devices with lower priorities.
836 If the device that currently owns the link, goes away, the symlink
837 will be removed, and recreated, pointing to the next device with the
838 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
839 more reliable, if multiple devices contain the same metadata and overwrite
842 The dasd_id program is removed from the udev tree, and dasdinfo, with the
843 needed rules, are part of the s390-tools now.
845 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
846 we may get the scsi sysfs mess fixed some day, and this will only catch
847 the devices we are looking for.
849 USB serial numbers for storage devices have the target:lun now appended,
850 to make it possibble to distinguish broken multi-lun devices with all
851 the same SCSI identifiers.
853 Note: The extra "run_directory" which searches and executes stuff in
854 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
855 with the next release. Make sure, that you don't use it anymore, or
856 provides your own implementation of that inefficient stuff.
857 We are tired of reports about a "slow udev", because these directories
858 contain stuff, that runs with _every_ event, instead of using rules,
859 that run programs only for the matching events.
869 DRIVER== will match only for devices that actually have a real
870 driver. DRIVERS== must be used, if parent devices should be
871 included in the match.
873 Libvolume_id's "linux_raid" detection needed another fix.
881 Add additional check to volume_id detection of via_raid, cause
882 some company decided to put a matching pattern all over the empty
883 storage area of their music players.
887 Fix path_id for SAS devices.
891 The udev daemon can be started with --debug-trace now, which will
892 execute all events serialized to get a chance to catch a possible
893 action that crashes the box.
895 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
896 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
897 are excluded from the warning. Referencing parent attributes directly
898 may break when something in the kernel driver model changes. Udev will
899 just find the attribute by walking up the parent chain.
901 Udevtrigger now sorts the list of devices depending on the device
902 dependency, so a "usb" device is triggered after the parent "pci"
907 Revert persistent-storage ata-serial '_' '-' replacement.
913 Udevtrigger can now filter the list of devices to be triggered. Matches
914 for subsystems or sysfs attributes can be specified.
916 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
917 zero-sized files to avoid pointing to /sys and confuse broken tools which
918 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
921 The rules and scripts to create udev rules for persistent network
922 devices and optical drives are in the extras/rules_generator directory
923 now. If you use something similar, please consider replacing your own
924 version with this, to share the support effort. The rule_generator
925 installs its own rules into /etc/udev/rules.d.
927 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
928 the rule_generator depends on cdrom_id to be called in an earlier rule.
934 Renaming of some key names (the old names still work):
935 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
936 (The behavior of the key DRIVER will change soon in one of the next
937 releases, to match only the event device, please switch to DRIVERS
938 instead. If DRIVER is used, it will behave like DRIVERS, but an error
940 With the new key names, we have a more consistent and simpler scheme.
941 We can match the properties of the event device only, with: KERNEL,
942 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
943 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
944 longer mentioned in the man page and should be switched in the rule
947 ATTR{file}="value" can be used now, to write to a sysfs file of the
948 event device. Instead of:
949 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
951 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
953 All the PHYSDEV* keys are deprecated and will be removed from a
955 PHYDEVPATH - is the path of a parent device and should not be
957 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
958 matched with SUBSYSTEMS==
959 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
960 Newer kernels will have DRIVER in the environment,
961 for older kernels udev puts in. Class device will
962 no longer carry this property of a parent and
963 DRIVERS== can be used to match such a parent value.
964 Note that ENV{DRIVER} is only available for a few bus devices, where
965 the driver is already bound at device event time. On coldplug, the
966 events for a lot devices are already bound to a driver, and they will have
967 that value set. But on hotplug, at the time the kernel creates the device,
968 it can't know what driver may claim the device after that, therefore
969 in most cases it will be empty.
971 Failed events should now be re-triggered with:
972 udevtrigger --retry-failed.
973 Please switch to this command, so we keep the details of the /dev/.udev/failed/
974 files private to the udev tools. We may need to switch the current symlink
975 target, cause some obviously broken tools try to scan all files in /dev
976 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
977 million times. This takes ages on slow boxes.
979 The udevinfo attribute walk (-a) now works with giving a device node
980 name (-n) instead of a devpath (-p). The query now always works, also when
981 no database file was created by udev.
983 The built-in /etc/passwd /etc/group parser is removed, we always depend on
984 getpwnam() and getgrnam() now. One of the next releases will depend on
985 fnmatch() and may use getopt_long().
989 Bugfixes and small improvements.
993 Fix path_id for recent kernels.
999 Added support for swapping network interface names, by temporarily
1000 renaming the device and wait for the target name to become free.
1004 The built-in MODALIAS key and substitution is removed.
1008 The binary firmware helper is replaced by the usual simple
1009 shell script. Udevsend is removed from the tree.
1017 Some more keys require the correct use of '==' and '=' depending
1018 on the kind of operation beeing an assignment or a match. Rules
1019 with invalid operations are skipped and logged to syslog. Please
1020 test with udevtest if the parsing of your rules throws errors and
1021 fix possibly broken rules.
1025 Provide "udevsettle" to wait for all current udev events to finish.
1026 It also watches the current kernel netlink queue by comparing the
1027 even sequence number to make sure that there are no current pending
1028 events that have not already arrived in the daemon.
1032 Fix rule to skip persistent rules for removable IDE devices, which
1033 also skipped optical IDE drives.
1035 All *_id program are installed in /lib/udev/ by default now.
1037 No binary is stripped anymore as this should be done in the
1038 packaging process and not at build time.
1040 libvolume_id is provided as a shared library now and vol_id is
1041 linked against it. Also one of the next HAL versions will require
1042 this library, and the HAL build process will also require the
1043 header file to be installed. The copy of the same code in HAL will
1044 be removed to have only a single copy left on the system.
1048 Add persistent links for SCSI tapes. The rules file is renamed
1049 to 60-persistent-storage.rules.
1051 Create persistent path for usb devices. Can be used for all sorts
1052 of devices that can't be distinguished by other properties like
1053 multiple identical keyboards and mice connected to the same box.
1055 Provide "udevtrigger" program to request events on coldplug. The
1056 shell script is much too slow with thousends of devices.
1060 Fix persistent disk rules to exclude removable IDE drives.
1062 Warn if %e, $modalias or MODALIAS is used.
1066 Fix queue export, which wasn't correct for subsequent add/remove
1067 events for the same device.
1071 Fix cramfs detection on big endian.
1073 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
1078 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
1079 attributes were only checked at the parent device that matched the
1080 by BUS requested subsystem. Fix it to also look at the device we
1081 received the event for.
1083 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
1088 Fix a bug where NAME="" would prevent RUN from beeing executed.
1090 RUN="/bin/program" does not longer automatically add the subsystem
1091 as the first parameter. This is from the days of /sbin/hotplug
1092 which is dead now and it's just confusing to need to add a space at
1093 the end of the program name to prevent this.
1094 If you use rules that need the subsystem as the first parameter,
1095 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
1096 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
1100 The udev man page has moved to udev(7) as it does not describe a command
1101 anymore. The programs udev, udevstart and udevsend are no longer installed
1102 by default and must be copied manually, if they should be installed or
1103 included in a package.
1105 Fix a bug where "ignore_device" could run earlier collected RUN keys before
1106 the ignore rule was applied.
1108 More preparation for future sysfs changes. usb_id and scsi_id no longer
1109 depend on a magic order of devices in the /devices chain. Specific devices
1110 should be requested by their subsytem.
1112 This will always find the scsi parent device without depending on a specific
1114 dev = sysfs_device_get(devpath);
1115 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
1117 The "device" link in the current sysfs layout will be automatically
1118 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
1119 parent in the devpath. If a device is requested by it's symlink, like all
1120 class devices in the new sysfs layout will look like, it gets automatically
1121 resolved and substituted with the real devpath and not the symlink path.
1124 A similar logic must be applied to _all_ sysfs users, including
1125 scripts, that search along parent devices in sysfs. The explicit use of
1126 the "device" link must be avoided. With the future sysfs layout all
1127 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
1128 back to the "class" or the "bus". The layout of the parent devices in
1129 /devices is not necessarily expected to be stable across kernel releases and
1130 searching for parents by their subsystem should make sysfs users tolerant
1131 for changed parent chains.
1135 Prepare udev to work with the experimental kernel patch, that moves
1136 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
1138 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
1139 moving the class devices to /sys/devices.
1141 Thanks again to Marco for help finding a hopefully nice compromise
1142 to make %b simpler and working again.
1146 Complete removal of libsysfs, replaced by simple helper functions
1147 which are much simpler and a bit faster. The udev daemon operatesentirely
1148 on event parameters and does not use sysfs for simple rules anymore.
1149 Please report any new bugs/problems, that may be caused by this big
1150 change. They will be fixed immediately.
1152 The enumeration format character '%e' is deprecated and will be
1153 removed sometimes from a future udev version. It never worked correctly
1154 outside of udevstart, so we can't use it with the new parallel
1155 coldplug. A simple enumeration is as useless as the devfs naming
1156 scheme, just get rid of both if you still use it.
1158 MODALIAS and $modalias is not needed and will be removed from one of
1159 the next udev versions, replace it in all rules with ENV{MODALIAS} or
1160 the sysfs "modalias" value.
1162 Thanks a lot to Marco for all his help on finding and fixing bugs.
1166 Let scsi_id request libata drive serial numbers from page 0x80.
1168 Renamed etc/udev/persistent.rules to persistent-disk.rules and
1169 added /dev/disk/by-name/* for device mapper device names.
1171 Removed %e from the man page. It never worked reliably outside
1172 of udevstart and udevstart is no longer recommended to use.
1176 Symlinks are now exported to the event environment. Hopefully it's no
1177 longer needed to run udevinfo from an event process, like it was
1178 mentioned on the hotplug list:
1179 UDEV [1134776873.702967] add@/block/sdb
1182 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
1186 Fix a problem if udevsend is used as the hotplug handler and tries to use
1187 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
1188 and this kind of problems will hopefully go away soon.
1192 All built-in logic to work around bad sysfs timing is removed with this
1193 version. The need to wait for sysfs files is almost fixed with a kernel
1194 version that doesn't work with this udev version anyway. Until we fix
1195 the timing of the "bus" link creation, the former integrated logic should
1196 be emulated by a rule placed before all other rules:
1197 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
1199 The option "udev_db" does no longer exist. All udev state will be in
1200 /$udev_root/.udev/ now, there is no longer an option to set this
1202 If the init script or something else used this value, just depend on
1203 this hardcoded path. But remember _all_content_ of this directory is
1204 still private to udev and can change at any time.
1206 Default location for rule sripts and helper programs is now: /lib/udev/.
1207 Everything that is not useful on the commandline should go into this
1208 directory. Some of the helpers in the extras folder are installed there
1209 now. The rules need to be changed, to find the helpers there.
1211 Also /lib/udev/devices is recommended as a directory where packages or
1212 the user can place real device nodes, which get copied over to /dev at
1213 every boot. This should replace the various solutions with custom config
1216 Udevsend does no longer start the udev daemon. This must be done with
1217 the init script that prepares /dev on tmpfs and creates the initial nodes,
1218 before starting the daemon.
1222 Silent a too verbose error logging for the old hotplug.d/ dev.d/
1225 The copy of klibc is removed. A systemwide installed version of klibc
1226 should be used to build a klibc udev now.
1230 NAME="" will not create any nodes, but execute RUN keys. To completely
1231 ignore an event the OPTION "ignore_device" should be used.
1233 After removal of the reorder queue, events with a TIMEOUT can be executed
1234 without any queuing now.
1238 Fixed bug in udevd, if inotify is not available. We depend on netlink
1239 uevents now, kernels without that event source will not work with that
1240 version of udev anymore.
1244 The rule parsing happens now in the daemon once at startup, all udev
1245 event processes inherit the already parsed rules from the daemon.
1246 It is shipped with SUSE10.0 and reduces heavily the system load at
1247 startup. The option to save precompiled rules and let the udev process
1248 pick the them up is removed, as it's no longer needed.
1250 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
1251 device. Libsysfs is changed to "translate" the requested link into the
1252 real device path, as it would happen with the hotplug event. Otherwise
1253 device removal and the udev database will not work.
1255 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
1258 A few improvements for vol_id, the filesytem probing code.
1262 Fix a stupid typo in extras/run_directory for "make install".
1264 scsi_id creates the temporary devnode now in /dev for usage with a
1265 non-writable /tmp directory.
1267 The uevent kernel socket buffer can carry app. 50.000 events now,
1268 let's see who can break this again. :)
1270 The upcoming kernel will have a new input driver core integration.
1271 Some class devices are now symlinks to the real device. libsysfs
1272 needs a fix for this to work correctly. Udevstart of older udev
1273 versions will _not_ create these devices!
1277 Fix a 'install' target in the Makefile, that prevents EXTRAS from
1282 A bunch of mostly trivial bugfixes. From now on no node name or
1283 symlink name can contain any character than plain whitelisted ascii
1284 characters or validated utf8 byte-streams. This is needed for the
1285 /dev/disk/by-label/* links, because we import untrusted data and
1286 export it to the filesystem.
1290 More bugfixes. If udevd was started from the kernel, we don't
1291 have stdin/stdout/stderr, which broke the forked tools in some
1296 Bugfix. udevstart event ordering was broken for a long time.
1297 The new run_program() uncovered it, because /dev/null was not
1298 available while we try to run external programs.
1299 Now udevstart should create it before we run anything.
1303 Minor bugfixes and some distro rules updates. If you don't have the
1304 persistent disk rules in /dev/disk/by-*/* on your distro, just
1305 grab it from here. :)
1309 We can use socket communication now to pass events from udev to
1311 RUN+="socket:/org/freedesktop/hal/udev_event"
1312 will pass the whole udev event to the HAL daemon without the need
1313 for a forked helper. (See ChangeLog for udevmonitor, as an example)
1317 Mostly bugfixes and see ChangeLog.
1319 The test for the existence of an environment value should be
1321 ENV{KEY}=="*" to ENV{KEY}=="?*"
1322 because "*" will not fail anymore, if the key does not exist or
1327 Bugfixes and a few tweaks described in the ChangeLog.
1331 Mostly a Bugfix release.
1333 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
1334 timing with custom rules.
1338 We changed the internal rule storage format. Our large rule files took
1339 2 MB of RAM, with the change we are down to 99kB.
1341 If the device-node has been created with default name and no symlink or
1342 options are to remenber, it is not longer stored in the udevdb. HAL will
1343 need to be updated to work correctly with that change.
1345 To overrride optimization flags, OPTFLAGS may be used now.
1353 Major changes happened with this release. The goal is to take over the
1354 complete kernel-event handling and provide a more efficient way to dispatch
1355 kernel events. Replacing most of the current shell script logic and the
1356 kernel forked helper with a netlink-daemon and a rule-based event handling.
1358 o udevd listens to netlink events now. The first valid netlink event
1359 will make udevd ignore any message from udevsend that contains a
1360 SEQNUM, to avoid duplicate events. The forked events can be disabled
1362 echo "" > /proc/sys/kernel/hotplug
1363 For full support, the broken input-subsytem needs to be fixed, not to
1364 bypass the driver core.
1366 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
1367 removed from udev itself and must be emulated by calling small
1368 helper binaries provided in the extras folder:
1369 make EXTRAS=extras/run_directory/
1370 will build udev_run_devd and udev_run_hotplugd, which can be called
1371 from a rule if needed:
1372 RUN+="/sbin/udev_run_hotplugd"
1373 The recommended way to handle this is to convert all the calls from
1374 the directories to explicit udev rules and get completely rid of the
1375 multiplexing. (To catch a ttyUSB event, you now no longer need to
1376 fork and exit 300 tty script instances you are not interested in, it
1377 is just one rule that matches exactly the device.)
1379 o udev handles now _all_ events not just events for class and block
1380 devices, this way it is possible to control the complete event
1381 behavior with udev rules. Especially useful for rules like:
1382 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
1384 o As used in the modalias rule, udev supports now textual
1385 substitution placeholder along with the usual format chars. This
1386 needs to be documented, for now it's only visible in udev_rules_parse.c.
1388 o The rule keys support now more operations. This is documented in the
1389 man page. It is possible to add values to list-keys like the SYMLINK
1390 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
1391 Also "final"-assignments are supported by using KEY:="value", which will
1392 prevent changing the key by any later rule.
1394 o kernel 2.6.12 has the "detached_state" attribute removed from
1395 sysfs, which was used to recognize sysfs population. We switched that
1396 to wait for the "bus" link, which is only available in kernels after 2.6.11.
1397 Running this udev version on older kernels may cause a short delay for
1400 o To provide infrastructure for persistent device naming, the id programs:
1401 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
1402 to export the probed data in environment key format:
1403 pim:~ # /sbin/ata_id --export /dev/hda
1404 ID_MODEL=HTS726060M9AT00
1405 ID_SERIAL=MRH401M4G6UM9B
1406 ID_REVISION=MH4OA6BA
1408 The following rules:
1409 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
1410 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
1413 kay@pim:~> tree /dev/disk
1416 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
1417 | `-- IBM-Memory_Key -> ../../sda
1419 | |-- swap -> ../../hda1
1420 | |-- date -> ../../sda1
1421 | `-- home -> ../../hda3
1423 |-- 2E08712B0870F2E7 -> ../../hda3
1424 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
1425 |-- E845-7A89 -> ../../sda1
1426 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
1428 The IMPORT= operation will import these keys in the environment and make
1429 it available for later PROGRAM= and RUN= executed programs. The keys are
1430 also stored in the udevdb and can be queried from there with one of the
1433 o A few binaries are silently added to the repository, which can be used
1434 to replay kernel events from initramfs instead of using coldplug. udevd
1435 can be instructed now to queue-up events while the stored events from
1436 initramfs are filled into the udevd-queue. This code is still under
1437 development and there is no documentation now besides the code itself.
1438 The additional binaries get compiled, but are not installed by default.
1440 o There is also a temporary fix for a performance problem where too many
1441 events happen in parallel and every event needs to parse the rules.
1442 udev can now read precompiled rules stored on disk. This is likely to be
1443 replaced by a more elegant solution in a future udev version.
1447 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
1448 Fix for libsysfs not to expect this file was added.
1452 All rules are applied now, but only the first matching rule with a NAME-key
1453 will be applied. All later rules with NAME-key are completely ignored. This
1454 way system supplied symlinks or permissions gets applied to user-defined
1458 Please check your rules setup, if you may need to add OPTIONS="last_rule"
1459 to some rules, to keep the old behavior.
1461 The rules are read on "remove"-events too. That makes is possible to match
1462 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
1463 instruct udev to ignore an event (OPTIONS="ignore_device").
1464 The new ACTION-key may be used to let a rule act only at a "remove"-event.
1466 The new RUN-key supports rule-based execution of programs after device-node
1467 handling. This is meant as a general replacement for the dev.d/-directories
1468 to give fine grained control over the execution of programs.
1470 The %s{}-sysfs format char replacement values are searched at any of the
1471 devices in the device chain now, not only at the class-device.
1473 We support log priority levels now. The value udev_log in udev.conf is used
1474 to determine what is printed to syslog. This makes it possible to
1475 run a version with compiled-in debug messages in a production environment
1476 which is sometimes needed to find a bug.
1477 It is still possible to supress the inclusion of _any_ syslog usage with
1478 USE_LOG=false to create the smallest possible binaries if needed.
1479 The configured udev_log value can be overridden with the environment variable
1484 Possible use of a system-wide klibc:
1485 make USE_KLIBC=true KLCC=/usr/bin/klcc all
1486 will link against an external klibc and our own version will be ignored.
1490 We support an unlimited count of symlinks now.
1492 If USE_STATIC=true is passed to a glibc build, we link statically and use
1493 a built-in userdb parser to resolve user and group names.
1495 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
1496 we walk up the chain of physical devices to find a match.
1498 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
1499 easy to skip certain attribute matches without composing rules with weird
1500 character class negations like:
1501 KERNEL="[!s][!c][!d]*"
1502 this can now be replaced with:
1504 The current simple '=' is still supported, and should work as it does today,
1505 but existing rules should be converted if possible, to be better readable.
1507 We have new ENV{}== key now, to match against a maximum of 5 environment
1510 udevstart is its own binary again, because we don't need co carry this araound
1511 with every forked event.