9 The udev runtime data moved from /dev/.udev/ to /run/udev/. The
10 /run mountpoint is supposed to be a tmpfs mounted during early boot,
11 available and writable to for all tools at any time during bootup,
12 it replaces /var/run/, which should become a symlink some day.
14 If /run does not exist, or is not writable, udev will fall back using
17 On systemd systems with initramfs and LVM used, packagers must
18 make sure, that the systemd and initramfs versions match. The initramfs
19 needs to create the /run mountpoint for udev to store the data, and
20 mount this tmpfs to /run in the rootfs, so the that the udev database
21 is preserved for the udev version started in the rootfs.
23 The command 'udevadm info --convert-db' is gone. The udev daemon
24 itself, at startup, converts any old database version if necessary.
26 The systemd services files have been reorganized. The udev control
27 socket is bound by systemd and passed to the started udev daemon.
28 The udev-settle.service is no longer active by default. Services which
29 can not handle hotplug setups properly need to actively pull it in, to
30 act like a barrier. Alternatively the settle service can be unconditionally
31 'systemctl'enabled, and act like a barrier for basic.target.
33 The fstab_import callout is no longer built or installed. Udev
34 should not be used to mount, does not watch changes to fstab, and
35 should not mirror fstab values in the udev database.
41 New and updated keymaps.
47 The udev database has changed, After installation of a new udev
48 version, 'udevadm info --convert-db' should be called, to let the new
49 udev/libudev version read the already stored data.
51 udevadm now supports quoting of property values, and prefixing of
53 $ udevadm info --export --export-prefix=MY_ --query=property -n sda
61 udev_device_get_is_initialized()
62 udev_enumerate_add_match_is_initialized()
63 to be able to skip devices the kernel has created , but udev has
67 udev_device_get_usec_since_initialized()
68 to retrieve the "age" of a udev device record.
70 GUdev supports a more generic GUdevEnumerator class, udev TAG
71 handling, device initialization and timestamp now.
73 The counterpart of /sys/dev/{char,block}/$major:$minor,
74 /dev/{char,block}/$major:$minor symlinks are now unconditionally
75 created, even when no rule files exist.
77 New and updated keymaps.
83 GUdev moved from /usr to /.
93 Persistent network naming rules are disabled inside of Qemu/KVM now.
95 New and updated keymaps.
97 Udev gets unconditionally enabled on systemd installations now. There
98 is no longer the need to to run 'systemctl enable udev.service'.
112 New and fixed keymaps.
114 Install systemd service files if applicable.
120 All distribution specific rules are removed from the udev source tree,
121 most of them are no longer needed. The Gentoo rules which allow to support
122 older kernel versions, which are not covered by the default rules anymore
123 has moved to rules/misc/30-kernel-compat.rules.
129 The option --debug-trace and the environemnt variable UDEVD_MAX_CHILDS=
130 was removed from udevd.
132 Udevd now checks the kernel commandline for the following variables:
133 udev.log-priority=<syslog priority>
134 udev.children-max=<maximum number of workers>
135 udev.exec-delay=<seconds to delay the execution of RUN=>
136 to help debuging coldplug setups where the loading of a kernel
137 module crashes the system.
139 The subdirectory in the source tree rules/packages has been renamed to
140 rules/arch, anc contains only architecture specific rules now.
150 Now the udev daemon itself, does on startup:
151 - copy the content of /lib/udev/devices to /dev
152 - create the standard symlinks like /dev/std{in,out,err},
153 /dev/core, /dev/fd, ...
154 - use static node information provided by kernel modules
155 and creates these nodes to allow module on-demand loading
156 - possibly apply permissions to all ststic nodes from udev
157 rules which are annotated to match a static node
159 The default mode for a device node is 0600 now to match the kernel
160 created devtmpfs defaults. If GROUP= is specified and no MODE= is
161 given the default will be 0660.
167 Udev now gradually starts to pass control over the primary device nodes
168 and their names to the kernel, and will in the end only manage the
169 permissions of the node, and possibly create additional symlinks.
170 As a first step NAME="" will be ignored, and NAME= setings with names
171 other than the kernel provided name will result in a logged warning.
172 Kernels that don't provide device names, or devtmpfs is not used, will
173 still work as they did before, but it is strongly recommended to use
174 only the same names for the primary device node as the recent kernel
175 provides for all devices.
179 Fix broken firmware loader search path.
185 "udevadm trigger" defaults to "change" events now instead of "add"
186 events. The "udev boot script" might need to add "--action=add" to
187 the trigger command if not already there, in case the initial coldplug
188 events are expected as "add" events.
190 The option "all_partitons" was removed from udev. This should not be
191 needed for usual hardware. Udev can not safely make assumptions
192 about non-existing partition major/minor numbers, and therefore no
193 longer provide this unreliable and unsafe option.
195 The option "ignore_remove" was removed from udev. With devtmpfs
196 udev passed control over device nodes to the kernel. This option
197 should not be needed, or can not work as advertised. Neither
198 udev nor the kernel will remove device nodes which are copied from
199 the /lib/udev/devices/ directory.
201 All "add|change" matches are replaced by "!remove" in the rules and
202 in the udev logic. All types of events will update possible symlinks
203 and permissions, only "remove" is handled special now.
205 The modem modeswitch extra was removed and the external usb_modeswitch
206 program should be used instead.
208 New and fixed keymaps.
218 Kernels with SYSFS_DEPRECATED=y are not supported since a while. Many users
219 depend on the current sysfs layout and the information not available in the
220 deprecated layout. All remaining support for the deprecated sysfs layout is
225 Fix for a possible endless loop in the new input_id program.
231 The option "ignore_device" does no longer exist. There is no way to
232 ignore an event, as libudev events can not be suppressed by rules.
233 It only prevented RUN keys from being executed, which results in an
234 inconsistent behavior in current setups.
236 BUS=, SYSFS{}=, ID= are long deprecated and should be SUBSYSTEM(S)=,
237 ATTR(S){}=, KERNEL(S)=. It will cause a warning once for every rule
240 The support for the deprecated IDE devices has been removed from the
241 default set of rules. Distros who still care about non-libata drivers
242 need to add the rules to the compat rules file.
244 The ID_CLASS property on input devices has been replaced by the more accurate
245 set of flags ID_INPUT_{KEYBOARD,KEY,MOUSE,TOUCHPAD,TABLET,JOYSTICK}. These are
246 determined by the new "input_id" prober now. Some devices, such as touchpads,
247 can have several classes. So if you previously had custom udev rules which e. g.
248 checked for ENV{ID_CLASS}=="kbd", you need to replace this with
249 ENV{ID_INPUT_KEYBOARD}=="?*".
255 To support DEVPATH strings larger than the maximum file name length, the
256 private udev database format has changed. If some software still reads the
257 private files in /dev/.udev/, which it shouldn't, now it's time to fix it.
258 Please do not port anything to the new format again, everything in /dev/.udev
259 is and always was private to udev, and may and will change any time without
262 Multiple devices claiming the same names in /dev are limited to symlinks
263 only now. Mixing identical symlink names and node names is not supported.
264 This reduces the amount of data in the database significantly.
266 NAME="%k" causes a warning now. It's is and always was completely superfluous.
267 It will break kernel supplied DEVNAMEs and therefore it needs to be removed
270 Most NAME= instructions got removed. Kernel 2.6.31 supplies the needed names
271 if they are not the default. To support older kernels, the NAME= rules need to
272 be added to the compat rules file.
274 Symlinks to udevadm with the old command names are no longer resolved to
275 the udevadm commands.
277 The udev-acl tool got adopted to changes in ConsoleKit. Version 0.4.1 is
280 The option "last_rule" does no longer exist. Its use breaks too many
281 things which expect to be run from independent later rules, and is an idication
282 that something needs to be fixed properly instead.
284 The gudev API is no longer marked as experimental,
285 G_UDEV_API_IS_SUBJECT_TO_CHANGE is no longer needed. The gudev introspection
286 is enabled by default now. Various projects already depend on introspection
287 information to bind dynamic languages to the gudev interfaces.
293 The udevadm trigger "--retry-failed" option, which is replaced since quite
294 a while by "--type=failed" is removed.
296 The failed tracking was not working at all for a few releases. The RUN
297 option "ignore_error" is replaced by a "fail_event_on_error" option, and the
298 default is not to track any failing RUN executions.
300 New keymaps, new modem, hid2hci updated.
304 Fix possible crash in udevd when worker processes are busy, rules are
305 changed at the same time, and workers get killed to reload the rules.
311 Properties set with ENV{.FOO}="bar" are marked private by starting the
312 name with a '.'. They will not be stored in the database, and not be
313 exported with the event.
315 Firmware files are looked up in:
316 /lib/firmware/updates/$(uname -r)
317 /lib/firmware/updates
318 /lib/firmware/$(uname -r)
322 ATA devices switched the property from ID_BUS=scsi to ID_BUS=ata.
323 ata_id, instead of scsi_id, is the default tool now for ATA devices.
329 The configure options have changed because another library needs to be
330 installed in a different location. Instead of exec_prefix and udev_prefix,
331 libdir, rootlibdir and libexecdir are used. The Details are explained in
334 Event processes now get re-used after they handled an event. This reduces
335 the number of forks and the pressure on the CPU significantly, because
336 cloned event processes no longer cause page faults in the main daemon.
337 After the events have settled, a few worker processes stay around for
338 future events, all others get cleaned up.
340 To be able to use signalfd(), udev depends on kernel version 2.6.25 now.
341 Also inotify support is mandatory now to run udev.
343 The format of the queue exported by the udev damon has changed. There is
344 no longer a /dev/.udev/queue/ directory. The current event queue can be
345 accessed with udevadm settle and libudedv.
347 Libudev does not have the unstable API header anymore. From now on,
348 incompatible changes will be handled by bumping the library major version.
350 To build udev from the git tree gtk-doc is needed now. The tarballs will
351 build without it and contain the pre-built documentation. An online copy
353 http://www.kernel.org/pub/linux/utils/kernel/hotplug/libudev/
355 The tools from the udev-extras repository have been merged into the main
356 udev repository. Some of the extras have larger external dependencies, and
357 they can be disabled with the configure switch --disable-extras.
363 The program vol_id and the library libvolume_id are removed from the
364 repository. Libvolume_id is merged with libblkid from the util-linux-ng
365 package. Persistent disk links for label and uuid depend on the
366 util-linux-ng version (2.15) of blkid now. Older versions of blkid
367 can not be used with udev.
369 Libudev allows to subscribe to udev events. To prevent unwanted messages
370 to be delivered, and waking up the subscribing process, a filter can be
371 installed, to drop messages inside a kernel socket filter. The filters
372 match on the <subsytem>:<devtype> properties of the device.
373 This is part of the ongoing effort to replace HAL, and switch current
374 users over to directly use libudev.
375 Libudev is still marked as experimental, and its interface might
376 eventually change if needed, but no major changes of the currently exported
377 interface are expected anymore, and a first stable release should happen
380 A too old kernel (2.6.21) or a kernel with CONFIG_SYSFS_DEPRECATED
381 is not supported since while and udevd will log an error message at
382 startup. It should still be able to boot-up, but advanced rules and system
383 services which depend on the information not available in the old sysfs
384 format will fail to work correctly.
386 DVB device naming is supplied by the kernel now. In case older kernels
387 need to be supported, the old shell script should be added to a compat
394 The processed udev events get send back to the netlink socket. Libudev
395 provides access to these events. This is work-in-progress, to replace
396 the DeviceKit daemon functionality directly with libudev. There are
397 upcoming kernel changes to allow non-root users to subcribe to these
404 "udevadm settle" now optionally accepts a range of events to wait for,
405 instead of waiting for "all" events.
411 The installed watch for block device metadata changes is now removed
412 during event hadling, because some (broken) tools may be called from udev
413 rules and (wrongly) open the device with write access. After the finished
414 event handling the watch is restored.
420 Device nodes can be watched for changes with inotify with OPTIONS="watch".
421 If closed after being opened for writing, a "change" uevent will occur.
422 /dev/disk/by-{label,uuid}/* symlinks will be automatically updated.
428 The udevadm test command has no longer a --force option, nodes and symlinks
429 are always updated with a test run now.
431 The udevd daemon can be started with --resolve-names=never to avoid all user
432 and group lookups (e.g. in cut-down systems) or --resolve-names=late to
433 lookup user and groups every time events are handled.
439 We are currently merging the Ubuntu rules in the udev default rules,
440 and get one step closer to provide a common Linux /dev setup, regarding
441 device names, symlinks, and default device permissions. On udev startup,
442 we now expect the following groups to be resolvable to their ids with
444 disk, cdrom, floppy, tape, audio, video, lp, tty, dialout, kmem.
445 LDAP setups need to make sure, that these groups are always resolvable at
446 bootup, with only the rootfs mounted, and without network access available.
448 Some systems may need to add some new, currently not used groups, or need
449 to add some users to new groups, but the cost of this change is minimal,
450 compared to the pain the current, rather random, differences between the
451 various distributions cause for upstream projects and third-party vendors.
453 In general, "normal" users who log into a machine should never be a member
454 of any such group, but the device-access should be managed by dynamic ACLs,
455 which get added and removed for the specific users on login/logout and
456 session activity/inactivity. These groups are only provided for custom setups,
457 and mainly system services, to allow proper privilege separation.
458 A video-streaming daemon uid would be a member of "audio" and "video", to get
459 access to the sound and video devices, but no "normal" user should ever belong
460 to the "audio" group, because he could listen to the built-in microphone with
461 any ssh-session established from the other side of the world.
463 /dev/serial/by-{id,path}/ now contains links for ttyUSB devices,
464 which do not depend on the kernel device name. As usual, unique
465 devices - only a single one per product connected, or a real
466 USB serial number in the device - are always found with the same
467 name in the by-id/ directory.
468 Completely identical devices may overwrite their names in by-id/
469 and can only be found reliably in the by-path/ directory. Devices
470 specified by by-path/ must not change their connection, like the
471 USB port number they are plugged in, to keep their name.
473 To support some advanced features, Linux 2.6.22 is the oldest supported
474 version now. The kernel config with enabled SYSFS_DEPRECATED is no longer
475 supported. Older kernels should still work, and devices nodes should be
476 reliably created, but some rules and libudev will not work correctly because
477 the old kernels do not provide the expected information or interfaces.
483 Fix for a possible segfault while swapping network interface names in udev
490 The group "video" is part of the default rules now.
494 Bugfix for kernels using SYSFS_DEPRECATED* option and finding parent
495 block devices in some cases. No common distro uses this option anymore,
496 and we do not get enough testing for this and recent udev versions. If
497 this option is not needed to run some old distro with a new kernel,
498 it should be disabled in the kernel config.
500 Bugfix for the $links substitution variable, which may crash if no links
501 are created. This should not happen in usual setups because we always
502 create /dev/{block,char}/ links.
504 The strings of the parsed rules, which are kept in memory, no longer
505 contain duplicate entries, or duplicate tails of strings. This, and the
506 new rules parsing/matching code reduces the total in-memory size of
507 a huge distro rule sets to 0.08 MB, compared to the 1.2MB of udev
510 The export of DEVTYPE=disk/partition got removed from the default
511 rules. This value is available from the kernel. The pnp shell script
512 modprobe hack is removed from the default rules. ACPI devices have _proper_
513 modalias support and take care of the same functionality.
514 Installations which support old kernels, but install current default
515 udev rules may want to add that to the compat rules file.
517 Libvolume_id now always probes for all known filesystems, and does not
518 stop at the first match. Some filesystems are marked as "exclusive probe",
519 and if any other filesytem type matches at the same time, libvolume_id
520 will, by default, not return any probing result. This is intended to prevent
521 mis-detection with conflicting left-over signatures found from earlier
522 file system formats. That way, we no longer depend on the probe-order
523 in case of multiple competing signatures. In some setups the kernel allows
524 to mount a volume with just the old filesystem signature still in place.
525 This may damage the new filesystem and cause data-loss, just by mounting
526 it. Because volume_id can not decide which one the correct signature is,
527 the wrong signatures need to be removed manually from the volume, or the
528 volume needs to be reformatted, to enable filesystem detection and possible
533 Fix segfault if compiled without optimization and dbg() does not get
534 compiled out and uses variables which are not available.
538 Bugfixes. (And maybe new bugs. :))
540 The rule matching engine got converted from a rule list to a token
541 array which reduced the in-memory rules representation of a full
542 featured distros with thousends of udev rules from 1.2MB to 0.12 MB.
543 Limits like 5 ENV and ATTR matches, and one single instance for most
544 other keys per rule are gone.
546 The NAME assignment is no longer special cased. If later rules assign
547 a NAME value again, the former value will be overwritten. As usual
548 for most other keys, the NAME value can be protected by doing a final
549 assignment with NAME:="<value>".
551 All udev code now uses libudev, which is also exported. The library
552 is still under development, marked as experimental, and its interface
553 may change as long as the DeviceKit integration is not finished.
555 Many thanks to Alan Jenkins for his continuous help, and finding and
556 optimizing some of the computing expensive parts.
562 Kernel devices and device nodes are connected now by reverse indizes in
563 /sys and /dev. A device number retrieved by a stat() or similar, the
564 kernel device directory can be found by looking up:
565 /sys/dev/{block,char}/<maj>:<min>
566 and the device node of the same device by looking up:
567 /dev/{block,char}/<maj>:<min>
571 Fix recently introduced bug, which caused a compilation without large
572 file support, where vol_id does not recognize raid signatures at the end
575 Firewire disks now create both, by-id/scsi-* and by-id/ieee-* links.
576 Seems some kernel versions prevent the creation of the ieee-* links,
577 so people used the scsi-* link which disappeared now.
579 More libudev work. Almost all udevadm functionality comes from libudev
582 udevadm trigger has a new option --type, which allows to trigger events
583 for "devices", for "subsystems", or "failed" devices. The old option
584 --retry-failed" still works, but is no longer mentioned in the man page.
590 The udevadm info --device-id-of-file= output has changed to use
591 the obvious format. Possible current users should use the --export
592 option which is not affected.
594 The old udev commands symlinks to udevadm are not installed, if
595 these symlinks are used, a warning is printed.
601 Optical drive's media is no longer probed for raid signatures,
602 reading the end of the device causes some devices to malfunction.
603 Also the offset of the last session found is used now to probe
606 The volume_id library got a major version number update to 1,
607 some deprecated functions are removed.
609 A shared library "libudev" gets installed now to provide access
610 to udev device information. DeviceKit, the successor of HAL, will
611 need this library to access the udev database and search sysfs for
613 The library is currently in an experimental state, also the API is
614 expected to change, as long as the DeviceKit integration is not
619 We use ./configure now. See INSTALL for details. Current
622 "/usr" - prefix for man pages, include files
624 "" - the root filesystem, prefix for libs and binaries
628 "lib" - directory name for libraries, not a path name
629 multilib 64bit systems may use "lib64" instead of "lib"
631 compile-in verbose debug messages
633 disable all logging and compile-out all log strings
635 link against SELInux libraries, to set the expected context
638 In the default rules, the group "disk" gets permissions 0660 instead
639 of 0640. One small step closer to unify distro rules. Some day, all
640 distros hopefully end up with the same set of rules.
642 No symlinks to udevadm are installed anymore, if they are still needed,
643 they should be provided by the package.
649 Default udev rules, which are not supposed to be edited by the user, should
650 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
651 the udev package and will be replaced with an update. Udev will pick up rule
653 /lib/udev/rules.d/ - default installed rules
654 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
655 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
656 It does not matter in which directory a rule file lives, all files are sorted
659 To help creating /dev/root, we have now:
660 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
663 In case the current --device-id-of-file is already used, please switch to
664 the --export format version, it saves the output parsing and the old
665 format will be changed to use ':' as a separator, like the format in the
670 Fix cdrom_id to properly recognize blank media.
676 Tape drive id-data is queried from /dev/bsg/* instead of the tape
677 nodes. This avoids rewinding tapes on open().
683 The symlinks udevcontrol and udevtrigger are no longer installed by
686 The scsi_id program does not depend on sysfs anymore. It can speak
687 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
688 data, which should solve some old problems with tape devices, where
689 we better do not open all tape device nodes to identify the device.
695 The cdrom_id program is replaced by an advanced version, which can
696 detect most common device types, and also properties of the inserted
697 media. This is part of moving some basic functionality from HAL into
698 udev (and the kernel).
704 The last WAIT_FOR_SYSFS rule is removed from the default rules.
706 The symlinks to udevadm for the debugging tools: udevmonitor and
707 udevtest are no longer created.
709 The symlinks to the udevadm man page for the old tool names are
712 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
713 should be prefixed with '@' to indicate that the path is not a
724 Udevstart is removed from the tree, it did not get installed for
725 a long time now, and is long replaced by trigger and settle.
731 All udev tools are merged into a single binary called udevadm.
732 The old names of the tools are built-in commands in udevadm now.
733 Symlinks to udevadm, with the names of the old tools, provide
734 the same functionality as the standalone tools. There is also
735 only a single udevadm.8 man page left for all tools.
737 Tools like mkinitramfs should be checked, if they need to include
738 udevadm in the list of files.
748 The etc/udev/rules.d/ directory now contains a default set of basic
749 udev rules. This initial version is the result of a rules file merge
750 of Fedora and openSUSE. For these both distros only a few specific
751 rules are left in their own file, named after the distro. Rules which
752 are optionally installed, because they are only valid for a specific
753 architecture, or rules for subsystems which are not always used are
754 in etc/udev/packages/.
760 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
761 actions by dynamically created rules.
763 SYMLINK=="<value>" matches agains the entries in the list of
764 currently defined symlinks. The links are not created in the
765 filesystem at that point in time, but the values can be matched.
767 RUN{ignore_error}+="<program>" will ignore any exit code from the
768 program and not record as a failed event.
774 Final merge of patches/features from the Ubuntu package.
780 Control characters in filesystem label strings are no longer silenty
781 removed, but hex-encoded, to be able to uniquely identify the device
782 by its symlink in /dev/disk/by-label/.
783 If libvolume_id is used by mount(8), LABEL= will work as expected,
784 if slashes or other characters are used in the label string.
786 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
787 can be specified now. The TEST key accepts an optional mode mask
788 TEST{0100}=="<is executable file>".
790 Scsi_id now supports a mode without expecting scsi-specific sysfs
791 entries to allow the extraction of cciss-device persistent properties.
797 In the future, we may see uuid's which are just simple character
798 strings (see the DDF Raid Specification). For that reason vol_id now
799 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
800 the creation of symlinks, the *_SAFE values ensure, that no control
801 or whitespace characters are used in the filename.
803 Possible users of libvolume_id, please use the volume_id_get_* functions.
804 The public struct will go away in a future release of the library.
810 Removal of useless extras/eventrecorder.sh.
820 The directory multiplexer for dev.d/ and hotplug.d are finally removed
821 from the udev package.
827 Symlinks can have priorities now, the priority is assigned to the device
828 and specified with OPTIONS="link_priority=100". Devices with higher
829 priorities overwrite the symlinks of devices with lower priorities.
830 If the device that currently owns the link, goes away, the symlink
831 will be removed, and recreated, pointing to the next device with the
832 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
833 more reliable, if multiple devices contain the same metadata and overwrite
836 The dasd_id program is removed from the udev tree, and dasdinfo, with the
837 needed rules, are part of the s390-tools now.
839 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
840 we may get the scsi sysfs mess fixed some day, and this will only catch
841 the devices we are looking for.
843 USB serial numbers for storage devices have the target:lun now appended,
844 to make it possibble to distinguish broken multi-lun devices with all
845 the same SCSI identifiers.
847 Note: The extra "run_directory" which searches and executes stuff in
848 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
849 with the next release. Make sure, that you don't use it anymore, or
850 provides your own implementation of that inefficient stuff.
851 We are tired of reports about a "slow udev", because these directories
852 contain stuff, that runs with _every_ event, instead of using rules,
853 that run programs only for the matching events.
863 DRIVER== will match only for devices that actually have a real
864 driver. DRIVERS== must be used, if parent devices should be
865 included in the match.
867 Libvolume_id's "linux_raid" detection needed another fix.
875 Add additional check to volume_id detection of via_raid, cause
876 some company decided to put a matching pattern all over the empty
877 storage area of their music players.
881 Fix path_id for SAS devices.
885 The udev daemon can be started with --debug-trace now, which will
886 execute all events serialized to get a chance to catch a possible
887 action that crashes the box.
889 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
890 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
891 are excluded from the warning. Referencing parent attributes directly
892 may break when something in the kernel driver model changes. Udev will
893 just find the attribute by walking up the parent chain.
895 Udevtrigger now sorts the list of devices depending on the device
896 dependency, so a "usb" device is triggered after the parent "pci"
901 Revert persistent-storage ata-serial '_' '-' replacement.
907 Udevtrigger can now filter the list of devices to be triggered. Matches
908 for subsystems or sysfs attributes can be specified.
910 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
911 zero-sized files to avoid pointing to /sys and confuse broken tools which
912 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
915 The rules and scripts to create udev rules for persistent network
916 devices and optical drives are in the extras/rules_generator directory
917 now. If you use something similar, please consider replacing your own
918 version with this, to share the support effort. The rule_generator
919 installs its own rules into /etc/udev/rules.d.
921 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
922 the rule_generator depends on cdrom_id to be called in an earlier rule.
928 Renaming of some key names (the old names still work):
929 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
930 (The behavior of the key DRIVER will change soon in one of the next
931 releases, to match only the event device, please switch to DRIVERS
932 instead. If DRIVER is used, it will behave like DRIVERS, but an error
934 With the new key names, we have a more consistent and simpler scheme.
935 We can match the properties of the event device only, with: KERNEL,
936 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
937 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
938 longer mentioned in the man page and should be switched in the rule
941 ATTR{file}="value" can be used now, to write to a sysfs file of the
942 event device. Instead of:
943 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
945 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
947 All the PHYSDEV* keys are deprecated and will be removed from a
949 PHYDEVPATH - is the path of a parent device and should not be
951 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
952 matched with SUBSYSTEMS==
953 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
954 Newer kernels will have DRIVER in the environment,
955 for older kernels udev puts in. Class device will
956 no longer carry this property of a parent and
957 DRIVERS== can be used to match such a parent value.
958 Note that ENV{DRIVER} is only available for a few bus devices, where
959 the driver is already bound at device event time. On coldplug, the
960 events for a lot devices are already bound to a driver, and they will have
961 that value set. But on hotplug, at the time the kernel creates the device,
962 it can't know what driver may claim the device after that, therefore
963 in most cases it will be empty.
965 Failed events should now be re-triggered with:
966 udevtrigger --retry-failed.
967 Please switch to this command, so we keep the details of the /dev/.udev/failed/
968 files private to the udev tools. We may need to switch the current symlink
969 target, cause some obviously broken tools try to scan all files in /dev
970 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
971 million times. This takes ages on slow boxes.
973 The udevinfo attribute walk (-a) now works with giving a device node
974 name (-n) instead of a devpath (-p). The query now always works, also when
975 no database file was created by udev.
977 The built-in /etc/passwd /etc/group parser is removed, we always depend on
978 getpwnam() and getgrnam() now. One of the next releases will depend on
979 fnmatch() and may use getopt_long().
983 Bugfixes and small improvements.
987 Fix path_id for recent kernels.
993 Added support for swapping network interface names, by temporarily
994 renaming the device and wait for the target name to become free.
998 The built-in MODALIAS key and substitution is removed.
1002 The binary firmware helper is replaced by the usual simple
1003 shell script. Udevsend is removed from the tree.
1011 Some more keys require the correct use of '==' and '=' depending
1012 on the kind of operation beeing an assignment or a match. Rules
1013 with invalid operations are skipped and logged to syslog. Please
1014 test with udevtest if the parsing of your rules throws errors and
1015 fix possibly broken rules.
1019 Provide "udevsettle" to wait for all current udev events to finish.
1020 It also watches the current kernel netlink queue by comparing the
1021 even sequence number to make sure that there are no current pending
1022 events that have not already arrived in the daemon.
1026 Fix rule to skip persistent rules for removable IDE devices, which
1027 also skipped optical IDE drives.
1029 All *_id program are installed in /lib/udev/ by default now.
1031 No binary is stripped anymore as this should be done in the
1032 packaging process and not at build time.
1034 libvolume_id is provided as a shared library now and vol_id is
1035 linked against it. Also one of the next HAL versions will require
1036 this library, and the HAL build process will also require the
1037 header file to be installed. The copy of the same code in HAL will
1038 be removed to have only a single copy left on the system.
1042 Add persistent links for SCSI tapes. The rules file is renamed
1043 to 60-persistent-storage.rules.
1045 Create persistent path for usb devices. Can be used for all sorts
1046 of devices that can't be distinguished by other properties like
1047 multiple identical keyboards and mice connected to the same box.
1049 Provide "udevtrigger" program to request events on coldplug. The
1050 shell script is much too slow with thousends of devices.
1054 Fix persistent disk rules to exclude removable IDE drives.
1056 Warn if %e, $modalias or MODALIAS is used.
1060 Fix queue export, which wasn't correct for subsequent add/remove
1061 events for the same device.
1065 Fix cramfs detection on big endian.
1067 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
1072 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
1073 attributes were only checked at the parent device that matched the
1074 by BUS requested subsystem. Fix it to also look at the device we
1075 received the event for.
1077 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
1082 Fix a bug where NAME="" would prevent RUN from beeing executed.
1084 RUN="/bin/program" does not longer automatically add the subsystem
1085 as the first parameter. This is from the days of /sbin/hotplug
1086 which is dead now and it's just confusing to need to add a space at
1087 the end of the program name to prevent this.
1088 If you use rules that need the subsystem as the first parameter,
1089 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
1090 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
1094 The udev man page has moved to udev(7) as it does not describe a command
1095 anymore. The programs udev, udevstart and udevsend are no longer installed
1096 by default and must be copied manually, if they should be installed or
1097 included in a package.
1099 Fix a bug where "ignore_device" could run earlier collected RUN keys before
1100 the ignore rule was applied.
1102 More preparation for future sysfs changes. usb_id and scsi_id no longer
1103 depend on a magic order of devices in the /devices chain. Specific devices
1104 should be requested by their subsytem.
1106 This will always find the scsi parent device without depending on a specific
1108 dev = sysfs_device_get(devpath);
1109 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
1111 The "device" link in the current sysfs layout will be automatically
1112 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
1113 parent in the devpath. If a device is requested by it's symlink, like all
1114 class devices in the new sysfs layout will look like, it gets automatically
1115 resolved and substituted with the real devpath and not the symlink path.
1118 A similar logic must be applied to _all_ sysfs users, including
1119 scripts, that search along parent devices in sysfs. The explicit use of
1120 the "device" link must be avoided. With the future sysfs layout all
1121 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
1122 back to the "class" or the "bus". The layout of the parent devices in
1123 /devices is not necessarily expected to be stable across kernel releases and
1124 searching for parents by their subsystem should make sysfs users tolerant
1125 for changed parent chains.
1129 Prepare udev to work with the experimental kernel patch, that moves
1130 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
1132 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
1133 moving the class devices to /sys/devices.
1135 Thanks again to Marco for help finding a hopefully nice compromise
1136 to make %b simpler and working again.
1140 Complete removal of libsysfs, replaced by simple helper functions
1141 which are much simpler and a bit faster. The udev daemon operatesentirely
1142 on event parameters and does not use sysfs for simple rules anymore.
1143 Please report any new bugs/problems, that may be caused by this big
1144 change. They will be fixed immediately.
1146 The enumeration format character '%e' is deprecated and will be
1147 removed sometimes from a future udev version. It never worked correctly
1148 outside of udevstart, so we can't use it with the new parallel
1149 coldplug. A simple enumeration is as useless as the devfs naming
1150 scheme, just get rid of both if you still use it.
1152 MODALIAS and $modalias is not needed and will be removed from one of
1153 the next udev versions, replace it in all rules with ENV{MODALIAS} or
1154 the sysfs "modalias" value.
1156 Thanks a lot to Marco for all his help on finding and fixing bugs.
1160 Let scsi_id request libata drive serial numbers from page 0x80.
1162 Renamed etc/udev/persistent.rules to persistent-disk.rules and
1163 added /dev/disk/by-name/* for device mapper device names.
1165 Removed %e from the man page. It never worked reliably outside
1166 of udevstart and udevstart is no longer recommended to use.
1170 Symlinks are now exported to the event environment. Hopefully it's no
1171 longer needed to run udevinfo from an event process, like it was
1172 mentioned on the hotplug list:
1173 UDEV [1134776873.702967] add@/block/sdb
1176 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
1180 Fix a problem if udevsend is used as the hotplug handler and tries to use
1181 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
1182 and this kind of problems will hopefully go away soon.
1186 All built-in logic to work around bad sysfs timing is removed with this
1187 version. The need to wait for sysfs files is almost fixed with a kernel
1188 version that doesn't work with this udev version anyway. Until we fix
1189 the timing of the "bus" link creation, the former integrated logic should
1190 be emulated by a rule placed before all other rules:
1191 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
1193 The option "udev_db" does no longer exist. All udev state will be in
1194 /$udev_root/.udev/ now, there is no longer an option to set this
1196 If the init script or something else used this value, just depend on
1197 this hardcoded path. But remember _all_content_ of this directory is
1198 still private to udev and can change at any time.
1200 Default location for rule sripts and helper programs is now: /lib/udev/.
1201 Everything that is not useful on the commandline should go into this
1202 directory. Some of the helpers in the extras folder are installed there
1203 now. The rules need to be changed, to find the helpers there.
1205 Also /lib/udev/devices is recommended as a directory where packages or
1206 the user can place real device nodes, which get copied over to /dev at
1207 every boot. This should replace the various solutions with custom config
1210 Udevsend does no longer start the udev daemon. This must be done with
1211 the init script that prepares /dev on tmpfs and creates the initial nodes,
1212 before starting the daemon.
1216 Silent a too verbose error logging for the old hotplug.d/ dev.d/
1219 The copy of klibc is removed. A systemwide installed version of klibc
1220 should be used to build a klibc udev now.
1224 NAME="" will not create any nodes, but execute RUN keys. To completely
1225 ignore an event the OPTION "ignore_device" should be used.
1227 After removal of the reorder queue, events with a TIMEOUT can be executed
1228 without any queuing now.
1232 Fixed bug in udevd, if inotify is not available. We depend on netlink
1233 uevents now, kernels without that event source will not work with that
1234 version of udev anymore.
1238 The rule parsing happens now in the daemon once at startup, all udev
1239 event processes inherit the already parsed rules from the daemon.
1240 It is shipped with SUSE10.0 and reduces heavily the system load at
1241 startup. The option to save precompiled rules and let the udev process
1242 pick the them up is removed, as it's no longer needed.
1244 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
1245 device. Libsysfs is changed to "translate" the requested link into the
1246 real device path, as it would happen with the hotplug event. Otherwise
1247 device removal and the udev database will not work.
1249 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
1252 A few improvements for vol_id, the filesytem probing code.
1256 Fix a stupid typo in extras/run_directory for "make install".
1258 scsi_id creates the temporary devnode now in /dev for usage with a
1259 non-writable /tmp directory.
1261 The uevent kernel socket buffer can carry app. 50.000 events now,
1262 let's see who can break this again. :)
1264 The upcoming kernel will have a new input driver core integration.
1265 Some class devices are now symlinks to the real device. libsysfs
1266 needs a fix for this to work correctly. Udevstart of older udev
1267 versions will _not_ create these devices!
1271 Fix a 'install' target in the Makefile, that prevents EXTRAS from
1276 A bunch of mostly trivial bugfixes. From now on no node name or
1277 symlink name can contain any character than plain whitelisted ascii
1278 characters or validated utf8 byte-streams. This is needed for the
1279 /dev/disk/by-label/* links, because we import untrusted data and
1280 export it to the filesystem.
1284 More bugfixes. If udevd was started from the kernel, we don't
1285 have stdin/stdout/stderr, which broke the forked tools in some
1290 Bugfix. udevstart event ordering was broken for a long time.
1291 The new run_program() uncovered it, because /dev/null was not
1292 available while we try to run external programs.
1293 Now udevstart should create it before we run anything.
1297 Minor bugfixes and some distro rules updates. If you don't have the
1298 persistent disk rules in /dev/disk/by-*/* on your distro, just
1299 grab it from here. :)
1303 We can use socket communication now to pass events from udev to
1305 RUN+="socket:/org/freedesktop/hal/udev_event"
1306 will pass the whole udev event to the HAL daemon without the need
1307 for a forked helper. (See ChangeLog for udevmonitor, as an example)
1311 Mostly bugfixes and see ChangeLog.
1313 The test for the existence of an environment value should be
1315 ENV{KEY}=="*" to ENV{KEY}=="?*"
1316 because "*" will not fail anymore, if the key does not exist or
1321 Bugfixes and a few tweaks described in the ChangeLog.
1325 Mostly a Bugfix release.
1327 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
1328 timing with custom rules.
1332 We changed the internal rule storage format. Our large rule files took
1333 2 MB of RAM, with the change we are down to 99kB.
1335 If the device-node has been created with default name and no symlink or
1336 options are to remenber, it is not longer stored in the udevdb. HAL will
1337 need to be updated to work correctly with that change.
1339 To overrride optimization flags, OPTFLAGS may be used now.
1347 Major changes happened with this release. The goal is to take over the
1348 complete kernel-event handling and provide a more efficient way to dispatch
1349 kernel events. Replacing most of the current shell script logic and the
1350 kernel forked helper with a netlink-daemon and a rule-based event handling.
1352 o udevd listens to netlink events now. The first valid netlink event
1353 will make udevd ignore any message from udevsend that contains a
1354 SEQNUM, to avoid duplicate events. The forked events can be disabled
1356 echo "" > /proc/sys/kernel/hotplug
1357 For full support, the broken input-subsytem needs to be fixed, not to
1358 bypass the driver core.
1360 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
1361 removed from udev itself and must be emulated by calling small
1362 helper binaries provided in the extras folder:
1363 make EXTRAS=extras/run_directory/
1364 will build udev_run_devd and udev_run_hotplugd, which can be called
1365 from a rule if needed:
1366 RUN+="/sbin/udev_run_hotplugd"
1367 The recommended way to handle this is to convert all the calls from
1368 the directories to explicit udev rules and get completely rid of the
1369 multiplexing. (To catch a ttyUSB event, you now no longer need to
1370 fork and exit 300 tty script instances you are not interested in, it
1371 is just one rule that matches exactly the device.)
1373 o udev handles now _all_ events not just events for class and block
1374 devices, this way it is possible to control the complete event
1375 behavior with udev rules. Especially useful for rules like:
1376 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
1378 o As used in the modalias rule, udev supports now textual
1379 substitution placeholder along with the usual format chars. This
1380 needs to be documented, for now it's only visible in udev_rules_parse.c.
1382 o The rule keys support now more operations. This is documented in the
1383 man page. It is possible to add values to list-keys like the SYMLINK
1384 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
1385 Also "final"-assignments are supported by using KEY:="value", which will
1386 prevent changing the key by any later rule.
1388 o kernel 2.6.12 has the "detached_state" attribute removed from
1389 sysfs, which was used to recognize sysfs population. We switched that
1390 to wait for the "bus" link, which is only available in kernels after 2.6.11.
1391 Running this udev version on older kernels may cause a short delay for
1394 o To provide infrastructure for persistent device naming, the id programs:
1395 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
1396 to export the probed data in environment key format:
1397 pim:~ # /sbin/ata_id --export /dev/hda
1398 ID_MODEL=HTS726060M9AT00
1399 ID_SERIAL=MRH401M4G6UM9B
1400 ID_REVISION=MH4OA6BA
1402 The following rules:
1403 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
1404 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
1407 kay@pim:~> tree /dev/disk
1410 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
1411 | `-- IBM-Memory_Key -> ../../sda
1413 | |-- swap -> ../../hda1
1414 | |-- date -> ../../sda1
1415 | `-- home -> ../../hda3
1417 |-- 2E08712B0870F2E7 -> ../../hda3
1418 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
1419 |-- E845-7A89 -> ../../sda1
1420 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
1422 The IMPORT= operation will import these keys in the environment and make
1423 it available for later PROGRAM= and RUN= executed programs. The keys are
1424 also stored in the udevdb and can be queried from there with one of the
1427 o A few binaries are silently added to the repository, which can be used
1428 to replay kernel events from initramfs instead of using coldplug. udevd
1429 can be instructed now to queue-up events while the stored events from
1430 initramfs are filled into the udevd-queue. This code is still under
1431 development and there is no documentation now besides the code itself.
1432 The additional binaries get compiled, but are not installed by default.
1434 o There is also a temporary fix for a performance problem where too many
1435 events happen in parallel and every event needs to parse the rules.
1436 udev can now read precompiled rules stored on disk. This is likely to be
1437 replaced by a more elegant solution in a future udev version.
1441 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
1442 Fix for libsysfs not to expect this file was added.
1446 All rules are applied now, but only the first matching rule with a NAME-key
1447 will be applied. All later rules with NAME-key are completely ignored. This
1448 way system supplied symlinks or permissions gets applied to user-defined
1452 Please check your rules setup, if you may need to add OPTIONS="last_rule"
1453 to some rules, to keep the old behavior.
1455 The rules are read on "remove"-events too. That makes is possible to match
1456 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
1457 instruct udev to ignore an event (OPTIONS="ignore_device").
1458 The new ACTION-key may be used to let a rule act only at a "remove"-event.
1460 The new RUN-key supports rule-based execution of programs after device-node
1461 handling. This is meant as a general replacement for the dev.d/-directories
1462 to give fine grained control over the execution of programs.
1464 The %s{}-sysfs format char replacement values are searched at any of the
1465 devices in the device chain now, not only at the class-device.
1467 We support log priority levels now. The value udev_log in udev.conf is used
1468 to determine what is printed to syslog. This makes it possible to
1469 run a version with compiled-in debug messages in a production environment
1470 which is sometimes needed to find a bug.
1471 It is still possible to supress the inclusion of _any_ syslog usage with
1472 USE_LOG=false to create the smallest possible binaries if needed.
1473 The configured udev_log value can be overridden with the environment variable
1478 Possible use of a system-wide klibc:
1479 make USE_KLIBC=true KLCC=/usr/bin/klcc all
1480 will link against an external klibc and our own version will be ignored.
1484 We support an unlimited count of symlinks now.
1486 If USE_STATIC=true is passed to a glibc build, we link statically and use
1487 a built-in userdb parser to resolve user and group names.
1489 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
1490 we walk up the chain of physical devices to find a match.
1492 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
1493 easy to skip certain attribute matches without composing rules with weird
1494 character class negations like:
1495 KERNEL="[!s][!c][!d]*"
1496 this can now be replaced with:
1498 The current simple '=' is still supported, and should work as it does today,
1499 but existing rules should be converted if possible, to be better readable.
1501 We have new ENV{}== key now, to match against a maximum of 5 environment
1504 udevstart is its own binary again, because we don't need co carry this araound
1505 with every forked event.