5 To support DEVPATH strings larger than the maximum file name length, the
6 private udev database format has changed. If some software still reads the
7 private files in /dev/.udev/, which it shouldn't, now it's time to fix it.
8 Please do not port anything to the new format again, everything in /dev/.udev
9 is and always was private to udev, and may and will change any time without
12 Multiple devices claiming the same names in /dev are limited to symlinks
13 only now. Mixing identical symlink names and node names is not supported.
14 This reduces the amount of data in the database significantly.
16 NAME="%k" causes a warning now. It's is and always was completely superfluous.
17 It will break kernel supplied DEVNAMEs and therefore it needs to be removed
20 Most NAME= instructions got removed. Kernel 2.6.31 supplies the needed names
21 if they are not the default. To support older kernels, the NAME= rules need to
22 be added to the compat rules file.
24 Symlinks to udevadm with the old command names are no longer resolved to
27 The udev-acl tool got adopted to changes in ConsoleKit. Version 0.4.11 is
30 The option "last_rule" does no longer exist. Its use breaks too many
31 things which expect to be run from independent later rules, and is an idication
32 that something needs to be fixed properly instead.
34 The gudev API is no longer marked as experimental,
35 G_UDEV_API_IS_SUBJECT_TO_CHANGE is no longer needed. The gudev introspection
36 is enabled by default now. Various projects already depend on introspection
37 information to bind dynamic languages to the gudev interfaces.
43 The udevadm trigger "--retry-failed" option, which is replaced since quite
44 a while by "--type=failed" is removed.
46 The failed tracking was not working at all for a few releases. The RUN
47 option "ignore_error" is replaced by a "fail_event_on_error" option, and the
48 default is not to track any failing RUN executions.
50 New keymaps, new modem, hid2hci updated.
54 Fix possible crash in udevd when worker processes are busy, rules are
55 changed at the same time, and workers get killed to reload the rules.
61 Properties set with ENV{.FOO}="bar" are marked private by starting the
62 name with a '.'. They will not be stored in the database, and not be
63 exported with the event.
65 Firmware files are looked up in:
66 /lib/firmware/updates/$(uname -r)
68 /lib/firmware/$(uname -r)
72 ATA devices switched the property from ID_BUS=scsi to ID_BUS=ata.
73 ata_id, instead of scsi_id, is the default tool now for ATA devices.
79 The configure options have changed because another library needs to be
80 installed in a different location. Instead of exec_prefix and udev_prefix,
81 libdir, rootlibdir and libexecdir are used. The Details are explained in
84 Event processes now get re-used after they handled an event. This reduces
85 the number of forks and the pressure on the CPU significantly, because
86 cloned event processes no longer cause page faults in the main daemon.
87 After the events have settled, a few worker processes stay around for
88 future events, all others get cleaned up.
90 To be able to use signalfd(), udev depends on kernel version 2.6.25 now.
91 Also inotify support is mandatory now to run udev.
93 The format of the queue exported by the udev damon has changed. There is
94 no longer a /dev/.udev/queue/ directory. The current event queue can be
95 accessed with udevadm settle and libudedv.
97 Libudev does not have the unstable API header anymore. From now on,
98 incompatible changes will be handled by bumping the library major version.
100 To build udev from the git tree gtk-doc is needed now. The tarballs will
101 build without it and contain the pre-built documentation. An online copy
103 http://www.kernel.org/pub/linux/utils/kernel/hotplug/libudev/
105 The tools from the udev-extras repository have been merged into the main
106 udev repository. Some of the extras have larger external dependencies, and
107 they can be disabled with the configure switch --disable-extras.
113 The program vol_id and the library libvolume_id are removed from the
114 repository. Libvolume_id is merged with libblkid from the util-linux-ng
115 package. Persistent disk links for label and uuid depend on the
116 util-linux-ng version (2.15) of blkid now. Older versions of blkid
117 can not be used with udev.
119 Libudev allows to subscribe to udev events. To prevent unwanted messages
120 to be delivered, and waking up the subscribing process, a filter can be
121 installed, to drop messages inside a kernel socket filter. The filters
122 match on the <subsytem>:<devtype> properties of the device.
123 This is part of the ongoing effort to replace HAL, and switch current
124 users over to directly use libudev.
125 Libudev is still marked as experimental, and its interface might
126 eventually change if needed, but no major changes of the currently exported
127 interface are expected anymore, and a first stable release should happen
130 A too old kernel (2.6.21) or a kernel with CONFIG_SYSFS_DEPRECATED
131 is not supported since while and udevd will log an error message at
132 startup. It should still be able to boot-up, but advanced rules and system
133 services which depend on the information not available in the old sysfs
134 format will fail to work correctly.
136 DVB device naming is supplied by the kernel now. In case older kernels
137 need to be supported, the old shell script should be added to a compat
144 The processed udev events get send back to the netlink socket. Libudev
145 provides access to these events. This is work-in-progress, to replace
146 the DeviceKit daemon functionality directly with libudev. There are
147 upcoming kernel changes to allow non-root users to subcribe to these
154 "udevadm settle" now optionally accepts a range of events to wait for,
155 instead of waiting for "all" events.
161 The installed watch for block device metadata changes is now removed
162 during event hadling, because some (broken) tools may be called from udev
163 rules and (wrongly) open the device with write access. After the finished
164 event handling the watch is restored.
170 Device nodes can be watched for changes with inotify with OPTIONS="watch".
171 If closed after being opened for writing, a "change" uevent will occur.
172 /dev/disk/by-{label,uuid}/* symlinks will be automatically updated.
178 The udevadm test command has no longer a --force option, nodes and symlinks
179 are always updated with a test run now.
181 The udevd daemon can be started with --resolve-names=never to avoid all user
182 and group lookups (e.g. in cut-down systems) or --resolve-names=late to
183 lookup user and groups every time events are handled.
189 We are currently merging the Ubuntu rules in the udev default rules,
190 and get one step closer to provide a common Linux /dev setup, regarding
191 device names, symlinks, and default device permissions. On udev startup,
192 we now expect the following groups to be resolvable to their ids with
194 disk, cdrom, floppy, tape, audio, video, lp, tty, dialout, kmem.
195 LDAP setups need to make sure, that these groups are always resolvable at
196 bootup, with only the rootfs mounted, and without network access available.
198 Some systems may need to add some new, currently not used groups, or need
199 to add some users to new groups, but the cost of this change is minimal,
200 compared to the pain the current, rather random, differences between the
201 various distributions cause for upstream projects and third-party vendors.
203 In general, "normal" users who log into a machine should never be a member
204 of any such group, but the device-access should be managed by dynamic ACLs,
205 which get added and removed for the specific users on login/logout and
206 session activity/inactivity. These groups are only provided for custom setups,
207 and mainly system services, to allow proper privilege separation.
208 A video-streaming daemon uid would be a member of "audio" and "video", to get
209 access to the sound and video devices, but no "normal" user should ever belong
210 to the "audio" group, because he could listen to the built-in microphone with
211 any ssh-session established from the other side of the world.
213 /dev/serial/by-{id,path}/ now contains links for ttyUSB devices,
214 which do not depend on the kernel device name. As usual, unique
215 devices - only a single one per product connected, or a real
216 USB serial number in the device - are always found with the same
217 name in the by-id/ directory.
218 Completely identical devices may overwrite their names in by-id/
219 and can only be found reliably in the by-path/ directory. Devices
220 specified by by-path/ must not change their connection, like the
221 USB port number they are plugged in, to keep their name.
223 To support some advanced features, Linux 2.6.22 is the oldest supported
224 version now. The kernel config with enabled SYSFS_DEPRECATED is no longer
225 supported. Older kernels should still work, and devices nodes should be
226 reliably created, but some rules and libudev will not work correctly because
227 the old kernels do not provide the expected information or interfaces.
233 Fix for a possible segfault while swapping network interface names in udev
240 The group "video" is part of the default rules now.
244 Bugfix for kernels using SYSFS_DEPRECATED* option and finding parent
245 block devices in some cases. No common distro uses this option anymore,
246 and we do not get enough testing for this and recent udev versions. If
247 this option is not needed to run some old distro with a new kernel,
248 it should be disabled in the kernel config.
250 Bugfix for the $links substitution variable, which may crash if no links
251 are created. This should not happen in usual setups because we always
252 create /dev/{block,char}/ links.
254 The strings of the parsed rules, which are kept in memory, no longer
255 contain duplicate entries, or duplicate tails of strings. This, and the
256 new rules parsing/matching code reduces the total in-memory size of
257 a huge distro rule sets to 0.08 MB, compared to the 1.2MB of udev
260 The export of DEVTYPE=disk/partition got removed from the default
261 rules. This value is available from the kernel. The pnp shell script
262 modprobe hack is removed from the default rules. ACPI devices have _proper_
263 modalias support and take care of the same functionality.
264 Installations which support old kernels, but install current default
265 udev rules may want to add that to the compat rules file.
267 Libvolume_id now always probes for all known filesystems, and does not
268 stop at the first match. Some filesystems are marked as "exclusive probe",
269 and if any other filesytem type matches at the same time, libvolume_id
270 will, by default, not return any probing result. This is intended to prevent
271 mis-detection with conflicting left-over signatures found from earlier
272 file system formats. That way, we no longer depend on the probe-order
273 in case of multiple competing signatures. In some setups the kernel allows
274 to mount a volume with just the old filesystem signature still in place.
275 This may damage the new filesystem and cause data-loss, just by mounting
276 it. Because volume_id can not decide which one the correct signature is,
277 the wrong signatures need to be removed manually from the volume, or the
278 volume needs to be reformatted, to enable filesystem detection and possible
283 Fix segfault if compiled without optimization and dbg() does not get
284 compiled out and uses variables which are not available.
288 Bugfixes. (And maybe new bugs. :))
290 The rule matching engine got converted from a rule list to a token
291 array which reduced the in-memory rules representation of a full
292 featured distros with thousends of udev rules from 1.2MB to 0.12 MB.
293 Limits like 5 ENV and ATTR matches, and one single instance for most
294 other keys per rule are gone.
296 The NAME assignment is no longer special cased. If later rules assign
297 a NAME value again, the former value will be overwritten. As usual
298 for most other keys, the NAME value can be protected by doing a final
299 assignment with NAME:="<value>".
301 All udev code now uses libudev, which is also exported. The library
302 is still under development, marked as experimental, and its interface
303 may change as long as the DeviceKit integration is not finished.
305 Many thanks to Alan Jenkins for his continuous help, and finding and
306 optimizing some of the computing expensive parts.
312 Kernel devices and device nodes are connected now by reverse indizes in
313 /sys and /dev. A device number retrieved by a stat() or similar, the
314 kernel device directory can be found by looking up:
315 /sys/dev/{block,char}/<maj>:<min>
316 and the device node of the same device by looking up:
317 /dev/{block,char}/<maj>:<min>
321 Fix recently introduced bug, which caused a compilation without large
322 file support, where vol_id does not recognize raid signatures at the end
325 Firewire disks now create both, by-id/scsi-* and by-id/ieee-* links.
326 Seems some kernel versions prevent the creation of the ieee-* links,
327 so people used the scsi-* link which disappeared now.
329 More libudev work. Almost all udevadm functionality comes from libudev
332 udevadm trigger has a new option --type, which allows to trigger events
333 for "devices", for "subsystems", or "failed" devices. The old option
334 --retry-failed" still works, but is no longer mentioned in the man page.
340 The udevadm info --device-id-of-file= output has changed to use
341 the obvious format. Possible current users should use the --export
342 option which is not affected.
344 The old udev commands symlinks to udevadm are not installed, if
345 these symlinks are used, a warning is printed.
351 Optical drive's media is no longer probed for raid signatures,
352 reading the end of the device causes some devices to malfunction.
353 Also the offset of the last session found is used now to probe
356 The volume_id library got a major version number update to 1,
357 some deprecated functions are removed.
359 A shared library "libudev" gets installed now to provide access
360 to udev device information. DeviceKit, the successor of HAL, will
361 need this library to access the udev database and search sysfs for
363 The library is currently in an experimental state, also the API is
364 expected to change, as long as the DeviceKit integration is not
369 We use ./configure now. See INSTALL for details. Current
372 "/usr" - prefix for man pages, include files
374 "" - the root filesystem, prefix for libs and binaries
378 "lib" - directory name for libraries, not a path name
379 multilib 64bit systems may use "lib64" instead of "lib"
381 compile-in verbose debug messages
383 disable all logging and compile-out all log strings
385 link against SELInux libraries, to set the expected context
388 In the default rules, the group "disk" gets permissions 0660 instead
389 of 0640. One small step closer to unify distro rules. Some day, all
390 distros hopefully end up with the same set of rules.
392 No symlinks to udevadm are installed anymore, if they are still needed,
393 they should be provided by the package.
399 Default udev rules, which are not supposed to be edited by the user, should
400 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
401 the udev package and will be replaced with an update. Udev will pick up rule
403 /lib/udev/rules.d/ - default installed rules
404 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
405 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
406 It does not matter in which directory a rule file lives, all files are sorted
409 To help creating /dev/root, we have now:
410 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
413 In case the current --device-id-of-file is already used, please switch to
414 the --export format version, it saves the output parsing and the old
415 format will be changed to use ':' as a separator, like the format in the
420 Fix cdrom_id to properly recognize blank media.
426 Tape drive id-data is queried from /dev/bsg/* instead of the tape
427 nodes. This avoids rewinding tapes on open().
433 The symlinks udevcontrol and udevtrigger are no longer installed by
436 The scsi_id program does not depend on sysfs anymore. It can speak
437 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
438 data, which should solve some old problems with tape devices, where
439 we better do not open all tape device nodes to identify the device.
445 The cdrom_id program is replaced by an advanced version, which can
446 detect most common device types, and also properties of the inserted
447 media. This is part of moving some basic functionality from HAL into
448 udev (and the kernel).
454 The last WAIT_FOR_SYSFS rule is removed from the default rules.
456 The symlinks to udevadm for the debugging tools: udevmonitor and
457 udevtest are no longer created.
459 The symlinks to the udevadm man page for the old tool names are
462 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
463 should be prefixed with '@' to indicate that the path is not a
474 Udevstart is removed from the tree, it did not get installed for
475 a long time now, and is long replaced by trigger and settle.
481 All udev tools are merged into a single binary called udevadm.
482 The old names of the tools are built-in commands in udevadm now.
483 Symlinks to udevadm, with the names of the old tools, provide
484 the same functionality as the standalone tools. There is also
485 only a single udevadm.8 man page left for all tools.
487 Tools like mkinitramfs should be checked, if they need to include
488 udevadm in the list of files.
498 The etc/udev/rules.d/ directory now contains a default set of basic
499 udev rules. This initial version is the result of a rules file merge
500 of Fedora and openSUSE. For these both distros only a few specific
501 rules are left in their own file, named after the distro. Rules which
502 are optionally installed, because they are only valid for a specific
503 architecture, or rules for subsystems which are not always used are
504 in etc/udev/packages/.
510 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
511 actions by dynamically created rules.
513 SYMLINK=="<value>" matches agains the entries in the list of
514 currently defined symlinks. The links are not created in the
515 filesystem at that point in time, but the values can be matched.
517 RUN{ignore_error}+="<program>" will ignore any exit code from the
518 program and not record as a failed event.
524 Final merge of patches/features from the Ubuntu package.
530 Control characters in filesystem label strings are no longer silenty
531 removed, but hex-encoded, to be able to uniquely identify the device
532 by its symlink in /dev/disk/by-label/.
533 If libvolume_id is used by mount(8), LABEL= will work as expected,
534 if slashes or other characters are used in the label string.
536 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
537 can be specified now. The TEST key accepts an optional mode mask
538 TEST{0100}=="<is executable file>".
540 Scsi_id now supports a mode without expecting scsi-specific sysfs
541 entries to allow the extraction of cciss-device persistent properties.
547 In the future, we may see uuid's which are just simple character
548 strings (see the DDF Raid Specification). For that reason vol_id now
549 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
550 the creation of symlinks, the *_SAFE values ensure, that no control
551 or whitespace characters are used in the filename.
553 Possible users of libvolume_id, please use the volume_id_get_* functions.
554 The public struct will go away in a future release of the library.
560 Removal of useless extras/eventrecorder.sh.
570 The directory multiplexer for dev.d/ and hotplug.d are finally removed
571 from the udev package.
577 Symlinks can have priorities now, the priority is assigned to the device
578 and specified with OPTIONS="link_priority=100". Devices with higher
579 priorities overwrite the symlinks of devices with lower priorities.
580 If the device that currently owns the link, goes away, the symlink
581 will be removed, and recreated, pointing to the next device with the
582 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
583 more reliable, if multiple devices contain the same metadata and overwrite
586 The dasd_id program is removed from the udev tree, and dasdinfo, with the
587 needed rules, are part of the s390-tools now.
589 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
590 we may get the scsi sysfs mess fixed some day, and this will only catch
591 the devices we are looking for.
593 USB serial numbers for storage devices have the target:lun now appended,
594 to make it possibble to distinguish broken multi-lun devices with all
595 the same SCSI identifiers.
597 Note: The extra "run_directory" which searches and executes stuff in
598 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
599 with the next release. Make sure, that you don't use it anymore, or
600 provides your own implementation of that inefficient stuff.
601 We are tired of reports about a "slow udev", because these directories
602 contain stuff, that runs with _every_ event, instead of using rules,
603 that run programs only for the matching events.
613 DRIVER== will match only for devices that actually have a real
614 driver. DRIVERS== must be used, if parent devices should be
615 included in the match.
617 Libvolume_id's "linux_raid" detection needed another fix.
625 Add additional check to volume_id detection of via_raid, cause
626 some company decided to put a matching pattern all over the empty
627 storage area of their music players.
631 Fix path_id for SAS devices.
635 The udev daemon can be started with --debug-trace now, which will
636 execute all events serialized to get a chance to catch a possible
637 action that crashes the box.
639 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
640 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
641 are excluded from the warning. Referencing parent attributes directly
642 may break when something in the kernel driver model changes. Udev will
643 just find the attribute by walking up the parent chain.
645 Udevtrigger now sorts the list of devices depending on the device
646 dependency, so a "usb" device is triggered after the parent "pci"
651 Revert persistent-storage ata-serial '_' '-' replacement.
657 Udevtrigger can now filter the list of devices to be triggered. Matches
658 for subsystems or sysfs attributes can be specified.
660 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
661 zero-sized files to avoid pointing to /sys and confuse broken tools which
662 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
665 The rules and scripts to create udev rules for persistent network
666 devices and optical drives are in the extras/rules_generator directory
667 now. If you use something similar, please consider replacing your own
668 version with this, to share the support effort. The rule_generator
669 installs its own rules into /etc/udev/rules.d.
671 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
672 the rule_generator depends on cdrom_id to be called in an earlier rule.
678 Renaming of some key names (the old names still work):
679 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
680 (The behavior of the key DRIVER will change soon in one of the next
681 releases, to match only the event device, please switch to DRIVERS
682 instead. If DRIVER is used, it will behave like DRIVERS, but an error
684 With the new key names, we have a more consistent and simpler scheme.
685 We can match the properties of the event device only, with: KERNEL,
686 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
687 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
688 longer mentioned in the man page and should be switched in the rule
691 ATTR{file}="value" can be used now, to write to a sysfs file of the
692 event device. Instead of:
693 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
695 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
697 All the PHYSDEV* keys are deprecated and will be removed from a
699 PHYDEVPATH - is the path of a parent device and should not be
701 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
702 matched with SUBSYSTEMS==
703 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
704 Newer kernels will have DRIVER in the environment,
705 for older kernels udev puts in. Class device will
706 no longer carry this property of a parent and
707 DRIVERS== can be used to match such a parent value.
708 Note that ENV{DRIVER} is only available for a few bus devices, where
709 the driver is already bound at device event time. On coldplug, the
710 events for a lot devices are already bound to a driver, and they will have
711 that value set. But on hotplug, at the time the kernel creates the device,
712 it can't know what driver may claim the device after that, therefore
713 in most cases it will be empty.
715 Failed events should now be re-triggered with:
716 udevtrigger --retry-failed.
717 Please switch to this command, so we keep the details of the /dev/.udev/failed/
718 files private to the udev tools. We may need to switch the current symlink
719 target, cause some obviously broken tools try to scan all files in /dev
720 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
721 million times. This takes ages on slow boxes.
723 The udevinfo attribute walk (-a) now works with giving a device node
724 name (-n) instead of a devpath (-p). The query now always works, also when
725 no database file was created by udev.
727 The built-in /etc/passwd /etc/group parser is removed, we always depend on
728 getpwnam() and getgrnam() now. One of the next releases will depend on
729 fnmatch() and may use getopt_long().
733 Bugfixes and small improvements.
737 Fix path_id for recent kernels.
743 Added support for swapping network interface names, by temporarily
744 renaming the device and wait for the target name to become free.
748 The built-in MODALIAS key and substitution is removed.
752 The binary firmware helper is replaced by the usual simple
753 shell script. Udevsend is removed from the tree.
761 Some more keys require the correct use of '==' and '=' depending
762 on the kind of operation beeing an assignment or a match. Rules
763 with invalid operations are skipped and logged to syslog. Please
764 test with udevtest if the parsing of your rules throws errors and
765 fix possibly broken rules.
769 Provide "udevsettle" to wait for all current udev events to finish.
770 It also watches the current kernel netlink queue by comparing the
771 even sequence number to make sure that there are no current pending
772 events that have not already arrived in the daemon.
776 Fix rule to skip persistent rules for removable IDE devices, which
777 also skipped optical IDE drives.
779 All *_id program are installed in /lib/udev/ by default now.
781 No binary is stripped anymore as this should be done in the
782 packaging process and not at build time.
784 libvolume_id is provided as a shared library now and vol_id is
785 linked against it. Also one of the next HAL versions will require
786 this library, and the HAL build process will also require the
787 header file to be installed. The copy of the same code in HAL will
788 be removed to have only a single copy left on the system.
792 Add persistent links for SCSI tapes. The rules file is renamed
793 to 60-persistent-storage.rules.
795 Create persistent path for usb devices. Can be used for all sorts
796 of devices that can't be distinguished by other properties like
797 multiple identical keyboards and mice connected to the same box.
799 Provide "udevtrigger" program to request events on coldplug. The
800 shell script is much too slow with thousends of devices.
804 Fix persistent disk rules to exclude removable IDE drives.
806 Warn if %e, $modalias or MODALIAS is used.
810 Fix queue export, which wasn't correct for subsequent add/remove
811 events for the same device.
815 Fix cramfs detection on big endian.
817 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
822 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
823 attributes were only checked at the parent device that matched the
824 by BUS requested subsystem. Fix it to also look at the device we
825 received the event for.
827 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
832 Fix a bug where NAME="" would prevent RUN from beeing executed.
834 RUN="/bin/program" does not longer automatically add the subsystem
835 as the first parameter. This is from the days of /sbin/hotplug
836 which is dead now and it's just confusing to need to add a space at
837 the end of the program name to prevent this.
838 If you use rules that need the subsystem as the first parameter,
839 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
840 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
844 The udev man page has moved to udev(7) as it does not describe a command
845 anymore. The programs udev, udevstart and udevsend are no longer installed
846 by default and must be copied manually, if they should be installed or
847 included in a package.
849 Fix a bug where "ignore_device" could run earlier collected RUN keys before
850 the ignore rule was applied.
852 More preparation for future sysfs changes. usb_id and scsi_id no longer
853 depend on a magic order of devices in the /devices chain. Specific devices
854 should be requested by their subsytem.
856 This will always find the scsi parent device without depending on a specific
858 dev = sysfs_device_get(devpath);
859 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
861 The "device" link in the current sysfs layout will be automatically
862 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
863 parent in the devpath. If a device is requested by it's symlink, like all
864 class devices in the new sysfs layout will look like, it gets automatically
865 resolved and substituted with the real devpath and not the symlink path.
868 A similar logic must be applied to _all_ sysfs users, including
869 scripts, that search along parent devices in sysfs. The explicit use of
870 the "device" link must be avoided. With the future sysfs layout all
871 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
872 back to the "class" or the "bus". The layout of the parent devices in
873 /devices is not necessarily expected to be stable across kernel releases and
874 searching for parents by their subsystem should make sysfs users tolerant
875 for changed parent chains.
879 Prepare udev to work with the experimental kernel patch, that moves
880 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
882 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
883 moving the class devices to /sys/devices.
885 Thanks again to Marco for help finding a hopefully nice compromise
886 to make %b simpler and working again.
890 Complete removal of libsysfs, replaced by simple helper functions
891 which are much simpler and a bit faster. The udev daemon operatesentirely
892 on event parameters and does not use sysfs for simple rules anymore.
893 Please report any new bugs/problems, that may be caused by this big
894 change. They will be fixed immediately.
896 The enumeration format character '%e' is deprecated and will be
897 removed sometimes from a future udev version. It never worked correctly
898 outside of udevstart, so we can't use it with the new parallel
899 coldplug. A simple enumeration is as useless as the devfs naming
900 scheme, just get rid of both if you still use it.
902 MODALIAS and $modalias is not needed and will be removed from one of
903 the next udev versions, replace it in all rules with ENV{MODALIAS} or
904 the sysfs "modalias" value.
906 Thanks a lot to Marco for all his help on finding and fixing bugs.
910 Let scsi_id request libata drive serial numbers from page 0x80.
912 Renamed etc/udev/persistent.rules to persistent-disk.rules and
913 added /dev/disk/by-name/* for device mapper device names.
915 Removed %e from the man page. It never worked reliably outside
916 of udevstart and udevstart is no longer recommended to use.
920 Symlinks are now exported to the event environment. Hopefully it's no
921 longer needed to run udevinfo from an event process, like it was
922 mentioned on the hotplug list:
923 UDEV [1134776873.702967] add@/block/sdb
926 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
930 Fix a problem if udevsend is used as the hotplug handler and tries to use
931 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
932 and this kind of problems will hopefully go away soon.
936 All built-in logic to work around bad sysfs timing is removed with this
937 version. The need to wait for sysfs files is almost fixed with a kernel
938 version that doesn't work with this udev version anyway. Until we fix
939 the timing of the "bus" link creation, the former integrated logic should
940 be emulated by a rule placed before all other rules:
941 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
943 The option "udev_db" does no longer exist. All udev state will be in
944 /$udev_root/.udev/ now, there is no longer an option to set this
946 If the init script or something else used this value, just depend on
947 this hardcoded path. But remember _all_content_ of this directory is
948 still private to udev and can change at any time.
950 Default location for rule sripts and helper programs is now: /lib/udev/.
951 Everything that is not useful on the commandline should go into this
952 directory. Some of the helpers in the extras folder are installed there
953 now. The rules need to be changed, to find the helpers there.
955 Also /lib/udev/devices is recommended as a directory where packages or
956 the user can place real device nodes, which get copied over to /dev at
957 every boot. This should replace the various solutions with custom config
960 Udevsend does no longer start the udev daemon. This must be done with
961 the init script that prepares /dev on tmpfs and creates the initial nodes,
962 before starting the daemon.
966 Silent a too verbose error logging for the old hotplug.d/ dev.d/
969 The copy of klibc is removed. A systemwide installed version of klibc
970 should be used to build a klibc udev now.
974 NAME="" will not create any nodes, but execute RUN keys. To completely
975 ignore an event the OPTION "ignore_device" should be used.
977 After removal of the reorder queue, events with a TIMEOUT can be executed
978 without any queuing now.
982 Fixed bug in udevd, if inotify is not available. We depend on netlink
983 uevents now, kernels without that event source will not work with that
984 version of udev anymore.
988 The rule parsing happens now in the daemon once at startup, all udev
989 event processes inherit the already parsed rules from the daemon.
990 It is shipped with SUSE10.0 and reduces heavily the system load at
991 startup. The option to save precompiled rules and let the udev process
992 pick the them up is removed, as it's no longer needed.
994 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
995 device. Libsysfs is changed to "translate" the requested link into the
996 real device path, as it would happen with the hotplug event. Otherwise
997 device removal and the udev database will not work.
999 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
1002 A few improvements for vol_id, the filesytem probing code.
1006 Fix a stupid typo in extras/run_directory for "make install".
1008 scsi_id creates the temporary devnode now in /dev for usage with a
1009 non-writable /tmp directory.
1011 The uevent kernel socket buffer can carry app. 50.000 events now,
1012 let's see who can break this again. :)
1014 The upcoming kernel will have a new input driver core integration.
1015 Some class devices are now symlinks to the real device. libsysfs
1016 needs a fix for this to work correctly. Udevstart of older udev
1017 versions will _not_ create these devices!
1021 Fix a 'install' target in the Makefile, that prevents EXTRAS from
1026 A bunch of mostly trivial bugfixes. From now on no node name or
1027 symlink name can contain any character than plain whitelisted ascii
1028 characters or validated utf8 byte-streams. This is needed for the
1029 /dev/disk/by-label/* links, because we import untrusted data and
1030 export it to the filesystem.
1034 More bugfixes. If udevd was started from the kernel, we don't
1035 have stdin/stdout/stderr, which broke the forked tools in some
1040 Bugfix. udevstart event ordering was broken for a long time.
1041 The new run_program() uncovered it, because /dev/null was not
1042 available while we try to run external programs.
1043 Now udevstart should create it before we run anything.
1047 Minor bugfixes and some distro rules updates. If you don't have the
1048 persistent disk rules in /dev/disk/by-*/* on your distro, just
1049 grab it from here. :)
1053 We can use socket communication now to pass events from udev to
1055 RUN+="socket:/org/freedesktop/hal/udev_event"
1056 will pass the whole udev event to the HAL daemon without the need
1057 for a forked helper. (See ChangeLog for udevmonitor, as an example)
1061 Mostly bugfixes and see ChangeLog.
1063 The test for the existence of an environment value should be
1065 ENV{KEY}=="*" to ENV{KEY}=="?*"
1066 because "*" will not fail anymore, if the key does not exist or
1071 Bugfixes and a few tweaks described in the ChangeLog.
1075 Mostly a Bugfix release.
1077 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
1078 timing with custom rules.
1082 We changed the internal rule storage format. Our large rule files took
1083 2 MB of RAM, with the change we are down to 99kB.
1085 If the device-node has been created with default name and no symlink or
1086 options are to remenber, it is not longer stored in the udevdb. HAL will
1087 need to be updated to work correctly with that change.
1089 To overrride optimization flags, OPTFLAGS may be used now.
1097 Major changes happened with this release. The goal is to take over the
1098 complete kernel-event handling and provide a more efficient way to dispatch
1099 kernel events. Replacing most of the current shell script logic and the
1100 kernel forked helper with a netlink-daemon and a rule-based event handling.
1102 o udevd listens to netlink events now. The first valid netlink event
1103 will make udevd ignore any message from udevsend that contains a
1104 SEQNUM, to avoid duplicate events. The forked events can be disabled
1106 echo "" > /proc/sys/kernel/hotplug
1107 For full support, the broken input-subsytem needs to be fixed, not to
1108 bypass the driver core.
1110 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
1111 removed from udev itself and must be emulated by calling small
1112 helper binaries provided in the extras folder:
1113 make EXTRAS=extras/run_directory/
1114 will build udev_run_devd and udev_run_hotplugd, which can be called
1115 from a rule if needed:
1116 RUN+="/sbin/udev_run_hotplugd"
1117 The recommended way to handle this is to convert all the calls from
1118 the directories to explicit udev rules and get completely rid of the
1119 multiplexing. (To catch a ttyUSB event, you now no longer need to
1120 fork and exit 300 tty script instances you are not interested in, it
1121 is just one rule that matches exactly the device.)
1123 o udev handles now _all_ events not just events for class and block
1124 devices, this way it is possible to control the complete event
1125 behavior with udev rules. Especially useful for rules like:
1126 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
1128 o As used in the modalias rule, udev supports now textual
1129 substitution placeholder along with the usual format chars. This
1130 needs to be documented, for now it's only visible in udev_rules_parse.c.
1132 o The rule keys support now more operations. This is documented in the
1133 man page. It is possible to add values to list-keys like the SYMLINK
1134 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
1135 Also "final"-assignments are supported by using KEY:="value", which will
1136 prevent changing the key by any later rule.
1138 o kernel 2.6.12 has the "detached_state" attribute removed from
1139 sysfs, which was used to recognize sysfs population. We switched that
1140 to wait for the "bus" link, which is only available in kernels after 2.6.11.
1141 Running this udev version on older kernels may cause a short delay for
1144 o To provide infrastructure for persistent device naming, the id programs:
1145 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
1146 to export the probed data in environment key format:
1147 pim:~ # /sbin/ata_id --export /dev/hda
1148 ID_MODEL=HTS726060M9AT00
1149 ID_SERIAL=MRH401M4G6UM9B
1150 ID_REVISION=MH4OA6BA
1152 The following rules:
1153 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
1154 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
1157 kay@pim:~> tree /dev/disk
1160 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
1161 | `-- IBM-Memory_Key -> ../../sda
1163 | |-- swap -> ../../hda1
1164 | |-- date -> ../../sda1
1165 | `-- home -> ../../hda3
1167 |-- 2E08712B0870F2E7 -> ../../hda3
1168 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
1169 |-- E845-7A89 -> ../../sda1
1170 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
1172 The IMPORT= operation will import these keys in the environment and make
1173 it available for later PROGRAM= and RUN= executed programs. The keys are
1174 also stored in the udevdb and can be queried from there with one of the
1177 o A few binaries are silently added to the repository, which can be used
1178 to replay kernel events from initramfs instead of using coldplug. udevd
1179 can be instructed now to queue-up events while the stored events from
1180 initramfs are filled into the udevd-queue. This code is still under
1181 development and there is no documentation now besides the code itself.
1182 The additional binaries get compiled, but are not installed by default.
1184 o There is also a temporary fix for a performance problem where too many
1185 events happen in parallel and every event needs to parse the rules.
1186 udev can now read precompiled rules stored on disk. This is likely to be
1187 replaced by a more elegant solution in a future udev version.
1191 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
1192 Fix for libsysfs not to expect this file was added.
1196 All rules are applied now, but only the first matching rule with a NAME-key
1197 will be applied. All later rules with NAME-key are completely ignored. This
1198 way system supplied symlinks or permissions gets applied to user-defined
1202 Please check your rules setup, if you may need to add OPTIONS="last_rule"
1203 to some rules, to keep the old behavior.
1205 The rules are read on "remove"-events too. That makes is possible to match
1206 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
1207 instruct udev to ignore an event (OPTIONS="ignore_device").
1208 The new ACTION-key may be used to let a rule act only at a "remove"-event.
1210 The new RUN-key supports rule-based execution of programs after device-node
1211 handling. This is meant as a general replacement for the dev.d/-directories
1212 to give fine grained control over the execution of programs.
1214 The %s{}-sysfs format char replacement values are searched at any of the
1215 devices in the device chain now, not only at the class-device.
1217 We support log priority levels now. The value udev_log in udev.conf is used
1218 to determine what is printed to syslog. This makes it possible to
1219 run a version with compiled-in debug messages in a production environment
1220 which is sometimes needed to find a bug.
1221 It is still possible to supress the inclusion of _any_ syslog usage with
1222 USE_LOG=false to create the smallest possible binaries if needed.
1223 The configured udev_log value can be overridden with the environment variable
1228 Possible use of a system-wide klibc:
1229 make USE_KLIBC=true KLCC=/usr/bin/klcc all
1230 will link against an external klibc and our own version will be ignored.
1234 We support an unlimited count of symlinks now.
1236 If USE_STATIC=true is passed to a glibc build, we link statically and use
1237 a built-in userdb parser to resolve user and group names.
1239 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
1240 we walk up the chain of physical devices to find a match.
1242 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
1243 easy to skip certain attribute matches without composing rules with weird
1244 character class negations like:
1245 KERNEL="[!s][!c][!d]*"
1246 this can now be replaced with:
1248 The current simple '=' is still supported, and should work as it does today,
1249 but existing rules should be converted if possible, to be better readable.
1251 We have new ENV{}== key now, to match against a maximum of 5 environment
1254 udevstart is its own binary again, because we don't need co carry this araound
1255 with every forked event.
~ianmdlvl / elogind.git / blob