5 The group "video" is part of the default rules now.
9 Bugfix for kernels using SYSFS_DEPRECATED* option and finding parent
10 block devices in some cases. No common distro uses this option anymore,
11 and we do not get enough testing for this and recent udev versions. If
12 this option is not needed to run some old distro with a new kernel,
13 it should be disabled in the kernel config.
15 Bugfix for the $links substitution variable, which may crash if no links
16 are created. This should not happen in usual setups because we always
17 create /dev/{block,char}/ links.
19 The strings of the parsed rules, which are kept in memory, no longer
20 contain duplicate entries, or duplicate tails of strings. This, and the
21 new rules parsing/matching code reduces the total in-memory size of
22 a huge distro rule sets to 0.08 MB, compared to the 1.2MB of udev
25 The export of DEVTYPE=disk/partition got removed from the default
26 rules. This value is available from the kernel. The pnp shell script
27 modprobe hack is removed from the default rules. ACPI devices have _proper_
28 modalias support and take care of the same functionality.
29 Installations which support old kernels, but install current default
30 udev rules may want to add that to the compat rules file.
32 Libvolume_id now always probes for all known filesystems, and does not
33 stop at the first match. Some filesystems are marked as "exclusive probe",
34 and if any other filesytem type matches at the same time, libvolume_id
35 will, by default, not return any probing result. This is intended to prevent
36 mis-detection with conflicting left-over signatures found from earlier
37 file system formats. That way, we no longer depend on the probe-order
38 in case of multiple competing signatures. In some setups the kernel allows
39 to mount a volume with just the old filesystem signature still in place.
40 This may damage the new filesystem and cause data-loss, just by mounting
41 it. Because volume_id can not decide which one the correct signature is,
42 the wrong signatures need to be removed manually from the volume, or the
43 volume needs to be reformatted, to enable filesystem detection and possible
48 Fix segfault if compiled without optimization and dbg() does not get
49 compiled out and uses variables which are not available.
53 Bugfixes. (And maybe new bugs. :))
55 The rule matching engine got converted from a rule list to a token
56 array which reduced the in-memory rules representation of a full
57 featured distros with thousends of udev rules from 1.2MB to 0.12 MB.
58 Limits like 5 ENV and ATTR matches, and one single instance for most
59 other keys per rule are gone.
61 The NAME assignment is no longer special cased. If later rules assign
62 a NAME value again, the former value will be overwritten. As usual
63 for most other keys, the NAME value can be protected by doing a final
64 assignment with NAME:="<value>".
66 All udev code now uses libudev, which is also exported. The library
67 is still under development, marked as experimental, and its interface
68 may change as long as the DeviceKit integration is not finished.
70 Many thanks to Alan Jenkins for his continuous help, and finding and
71 optimizing some of the computing expensive parts.
77 Kernel devices and device nodes are connected now by reverse indizes in
78 /sys and /dev. A device number retrieved by a stat() or similar, the
79 kernel device directory can be found by looking up:
80 /sys/dev/{block,char}/<maj>:<min>
81 and the device node of the same device by looking up:
82 /dev/{block,char}/<maj>:<min>
86 Fix recently introduced bug, which caused a compilation without large
87 file support, where vol_id does not recognize raid signatures at the end
90 Firewire disks now create both, by-id/scsi-* and by-id/ieee-* links.
91 Seems some kernel versions prevent the creation of the ieee-* links,
92 so people used the scsi-* link which disappeared now.
94 More libudev work. Almost all udevadm functionality comes from libudev
97 udevadm trigger has a new option --type, which allows to trigger events
98 for "devices", for "subsystems", or "failed" devices. The old option
99 --retry-failed" still works, but is no longer mentioned in the man page.
105 The udevadm info --device-id-of-file= output has changed to use
106 the obvious format. Possible current users should use the --export
107 option which is not affected.
109 The old udev commands symlinks to udevadm are not installed, if
110 these symlinks are used, a warning is printed.
116 Optical drive's media is no longer probed for raid signatures,
117 reading the end of the device causes some devices to malfunction.
118 Also the offset of the last session found is used now to probe
121 The volume_id library got a major version number update to 1,
122 some deprecated functions are removed.
124 A shared library "libudev" gets installed now to provide access
125 to udev device information. DeviceKit, the successor of HAL, will
126 need this library to access the udev database and search sysfs for
128 The library is currently in an experimental state, also the API is
129 expected to change, as long as the DeviceKit integration is not
134 We use ./configure now. See INSTALL for details. Current
137 "/usr" - prefix for man pages, include files
139 "" - the root filesystem, prefix for libs and binaries
143 "lib" - directory name for libraries, not a path name
144 multilib 64bit systems may use "lib64" instead of "lib"
146 compile-in verbose debug messages
148 disable all logging and compile-out all log strings
150 link against SELInux libraries, to set the expected context
153 In the default rules, the group "disk" gets permissions 0660 instead
154 of 0640. One small step closer to unify distro rules. Some day, all
155 distros hopefully end up with the same set of rules.
157 No symlinks to udevadm are installed anymore, if they are still needed,
158 they should be provided by the package.
164 Default udev rules, which are not supposed to be edited by the user, should
165 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
166 the udev package and will be replaced with an update. Udev will pick up rule
168 /lib/udev/rules.d/ - default installed rules
169 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
170 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
171 It does not matter in which directory a rule file lives, all files are sorted
174 To help creating /dev/root, we have now:
175 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
178 In case the current --device-id-of-file is already used, please switch to
179 the --export format version, it saves the output parsing and the old
180 format will be changed to use ':' as a separator, like the format in the
185 Fix cdrom_id to properly recognize blank media.
191 Tape drive id-data is queried from /dev/bsg/* instead of the tape
192 nodes. This avoids rewinding tapes on open().
198 The symlinks udevcontrol and udevtrigger are no longer installed by
201 The scsi_id program does not depend on sysfs anymore. It can speak
202 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
203 data, which should solve some old problems with tape devices, where
204 we better do not open all tape device nodes to identify the device.
210 The cdrom_id program is replaced by an advanced version, which can
211 detect most common device types, and also properties of the inserted
212 media. This is part of moving some basic functionality from HAL into
213 udev (and the kernel).
219 The last WAIT_FOR_SYSFS rule is removed from the default rules.
221 The symlinks to udevadm for the debugging tools: udevmonitor and
222 udevtest are no longer created.
224 The symlinks to the udevadm man page for the old tool names are
227 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
228 should be prefixed with '@' to indicate that the path is not a
239 Udevstart is removed from the tree, it did not get installed for
240 a long time now, and is long replaced by trigger and settle.
246 All udev tools are merged into a single binary called udevadm.
247 The old names of the tools are built-in commands in udevadm now.
248 Symlinks to udevadm, with the names of the old tools, provide
249 the same functionality as the standalone tools. There is also
250 only a single udevadm.8 man page left for all tools.
252 Tools like mkinitramfs should be checked, if they need to include
253 udevadm in the list of files.
263 The etc/udev/rules.d/ directory now contains a default set of basic
264 udev rules. This initial version is the result of a rules file merge
265 of Fedora and openSUSE. For these both distros only a few specific
266 rules are left in their own file, named after the distro. Rules which
267 are optionally installed, because they are only valid for a specific
268 architecture, or rules for subsystems which are not always used are
269 in etc/udev/packages/.
275 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
276 actions by dynamically created rules.
278 SYMLINK=="<value>" matches agains the entries in the list of
279 currently defined symlinks. The links are not created in the
280 filesystem at that point in time, but the values can be matched.
282 RUN{ignore_error}+="<program>" will ignore any exit code from the
283 program and not record as a failed event.
289 Final merge of patches/features from the Ubuntu package.
295 Control characters in filesystem label strings are no longer silenty
296 removed, but hex-encoded, to be able to uniquely identify the device
297 by its symlink in /dev/disk/by-label/.
298 If libvolume_id is used by mount(8), LABEL= will work as expected,
299 if slashes or other characters are used in the label string.
301 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
302 can be specified now. The TEST key accepts an optional mode mask
303 TEST{0100}=="<is executable file>".
305 Scsi_id now supports a mode without expecting scsi-specific sysfs
306 entries to allow the extraction of cciss-device persistent properties.
312 In the future, we may see uuid's which are just simple character
313 strings (see the DDF Raid Specification). For that reason vol_id now
314 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
315 the creation of symlinks, the *_SAFE values ensure, that no control
316 or whitespace characters are used in the filename.
318 Possible users of libvolume_id, please use the volume_id_get_* functions.
319 The public struct will go away in a future release of the library.
325 Removal of useless extras/eventrecorder.sh.
335 The directory multiplexer for dev.d/ and hotplug.d are finally removed
336 from the udev package.
342 Symlinks can have priorities now, the priority is assigned to the device
343 and specified with OPTIONS="link_priority=100". Devices with higher
344 priorities overwrite the symlinks of devices with lower priorities.
345 If the device that currently owns the link, goes away, the symlink
346 will be removed, and recreated, pointing to the next device with the
347 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
348 more reliable, if multiple devices contain the same metadata and overwrite
351 The dasd_id program is removed from the udev tree, and dasdinfo, with the
352 needed rules, are part of the s390-tools now.
354 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
355 we may get the scsi sysfs mess fixed some day, and this will only catch
356 the devices we are looking for.
358 USB serial numbers for storage devices have the target:lun now appended,
359 to make it possibble to distinguish broken multi-lun devices with all
360 the same SCSI identifiers.
362 Note: The extra "run_directory" which searches and executes stuff in
363 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
364 with the next release. Make sure, that you don't use it anymore, or
365 provides your own implementation of that inefficient stuff.
366 We are tired of reports about a "slow udev", because these directories
367 contain stuff, that runs with _every_ event, instead of using rules,
368 that run programs only for the matching events.
378 DRIVER== will match only for devices that actually have a real
379 driver. DRIVERS== must be used, if parent devices should be
380 included in the match.
382 Libvolume_id's "linux_raid" detection needed another fix.
390 Add additional check to volume_id detection of via_raid, cause
391 some company decided to put a matching pattern all over the empty
392 storage area of their music players.
396 Fix path_id for SAS devices.
400 The udev daemon can be started with --debug-trace now, which will
401 execute all events serialized to get a chance to catch a possible
402 action that crashes the box.
404 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
405 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
406 are excluded from the warning. Referencing parent attributes directly
407 may break when something in the kernel driver model changes. Udev will
408 just find the attribute by walking up the parent chain.
410 Udevtrigger now sorts the list of devices depending on the device
411 dependency, so a "usb" device is triggered after the parent "pci"
416 Revert persistent-storage ata-serial '_' '-' replacement.
422 Udevtrigger can now filter the list of devices to be triggered. Matches
423 for subsystems or sysfs attributes can be specified.
425 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
426 zero-sized files to avoid pointing to /sys and confuse broken tools which
427 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
430 The rules and scripts to create udev rules for persistent network
431 devices and optical drives are in the extras/rules_generator directory
432 now. If you use something similar, please consider replacing your own
433 version with this, to share the support effort. The rule_generator
434 installs its own rules into /etc/udev/rules.d.
436 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
437 the rule_generator depends on cdrom_id to be called in an earlier rule.
443 Renaming of some key names (the old names still work):
444 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
445 (The behavior of the key DRIVER will change soon in one of the next
446 releases, to match only the event device, please switch to DRIVERS
447 instead. If DRIVER is used, it will behave like DRIVERS, but an error
449 With the new key names, we have a more consistent and simpler scheme.
450 We can match the properties of the event device only, with: KERNEL,
451 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
452 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
453 longer mentioned in the man page and should be switched in the rule
456 ATTR{file}="value" can be used now, to write to a sysfs file of the
457 event device. Instead of:
458 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
460 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
462 All the PHYSDEV* keys are deprecated and will be removed from a
464 PHYDEVPATH - is the path of a parent device and should not be
466 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
467 matched with SUBSYSTEMS==
468 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
469 Newer kernels will have DRIVER in the environment,
470 for older kernels udev puts in. Class device will
471 no longer carry this property of a parent and
472 DRIVERS== can be used to match such a parent value.
473 Note that ENV{DRIVER} is only available for a few bus devices, where
474 the driver is already bound at device event time. On coldplug, the
475 events for a lot devices are already bound to a driver, and they will have
476 that value set. But on hotplug, at the time the kernel creates the device,
477 it can't know what driver may claim the device after that, therefore
478 in most cases it will be empty.
480 Failed events should now be re-triggered with:
481 udevtrigger --retry-failed.
482 Please switch to this command, so we keep the details of the /dev/.udev/failed/
483 files private to the udev tools. We may need to switch the current symlink
484 target, cause some obviously broken tools try to scan all files in /dev
485 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
486 million times. This takes ages on slow boxes.
488 The udevinfo attribute walk (-a) now works with giving a device node
489 name (-n) instead of a devpath (-p). The query now always works, also when
490 no database file was created by udev.
492 The built-in /etc/passwd /etc/group parser is removed, we always depend on
493 getpwnam() and getgrnam() now. One of the next releases will depend on
494 fnmatch() and may use getopt_long().
498 Bugfixes and small improvements.
502 Fix path_id for recent kernels.
508 Added support for swapping network interface names, by temporarily
509 renaming the device and wait for the target name to become free.
513 The built-in MODALIAS key and substitution is removed.
517 The binary firmware helper is replaced by the usual simple
518 shell script. Udevsend is removed from the tree.
526 Some more keys require the correct use of '==' and '=' depending
527 on the kind of operation beeing an assignment or a match. Rules
528 with invalid operations are skipped and logged to syslog. Please
529 test with udevtest if the parsing of your rules throws errors and
530 fix possibly broken rules.
534 Provide "udevsettle" to wait for all current udev events to finish.
535 It also watches the current kernel netlink queue by comparing the
536 even sequence number to make sure that there are no current pending
537 events that have not already arrived in the daemon.
541 Fix rule to skip persistent rules for removable IDE devices, which
542 also skipped optical IDE drives.
544 All *_id program are installed in /lib/udev/ by default now.
546 No binary is stripped anymore as this should be done in the
547 packaging process and not at build time.
549 libvolume_id is provided as a shared library now and vol_id is
550 linked against it. Also one of the next HAL versions will require
551 this library, and the HAL build process will also require the
552 header file to be installed. The copy of the same code in HAL will
553 be removed to have only a single copy left on the system.
557 Add persistent links for SCSI tapes. The rules file is renamed
558 to 60-persistent-storage.rules.
560 Create persistent path for usb devices. Can be used for all sorts
561 of devices that can't be distinguished by other properties like
562 multiple identical keyboards and mice connected to the same box.
564 Provide "udevtrigger" program to request events on coldplug. The
565 shell script is much too slow with thousends of devices.
569 Fix persistent disk rules to exclude removable IDE drives.
571 Warn if %e, $modalias or MODALIAS is used.
575 Fix queue export, which wasn't correct for subsequent add/remove
576 events for the same device.
580 Fix cramfs detection on big endian.
582 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
587 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
588 attributes were only checked at the parent device that matched the
589 by BUS requested subsystem. Fix it to also look at the device we
590 received the event for.
592 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
597 Fix a bug where NAME="" would prevent RUN from beeing executed.
599 RUN="/bin/program" does not longer automatically add the subsystem
600 as the first parameter. This is from the days of /sbin/hotplug
601 which is dead now and it's just confusing to need to add a space at
602 the end of the program name to prevent this.
603 If you use rules that need the subsystem as the first parameter,
604 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
605 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
609 The udev man page has moved to udev(7) as it does not describe a command
610 anymore. The programs udev, udevstart and udevsend are no longer installed
611 by default and must be copied manually, if they should be installed or
612 included in a package.
614 Fix a bug where "ignore_device" could run earlier collected RUN keys before
615 the ignore rule was applied.
617 More preparation for future sysfs changes. usb_id and scsi_id no longer
618 depend on a magic order of devices in the /devices chain. Specific devices
619 should be requested by their subsytem.
621 This will always find the scsi parent device without depending on a specific
623 dev = sysfs_device_get(devpath);
624 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
626 The "device" link in the current sysfs layout will be automatically
627 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
628 parent in the devpath. If a device is requested by it's symlink, like all
629 class devices in the new sysfs layout will look like, it gets automatically
630 resolved and substituted with the real devpath and not the symlink path.
633 A similar logic must be applied to _all_ sysfs users, including
634 scripts, that search along parent devices in sysfs. The explicit use of
635 the "device" link must be avoided. With the future sysfs layout all
636 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
637 back to the "class" or the "bus". The layout of the parent devices in
638 /devices is not necessarily expected to be stable across kernel releases and
639 searching for parents by their subsystem should make sysfs users tolerant
640 for changed parent chains.
644 Prepare udev to work with the experimental kernel patch, that moves
645 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
647 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
648 moving the class devices to /sys/devices.
650 Thanks again to Marco for help finding a hopefully nice compromise
651 to make %b simpler and working again.
655 Complete removal of libsysfs, replaced by simple helper functions
656 which are much simpler and a bit faster. The udev daemon operatesentirely
657 on event parameters and does not use sysfs for simple rules anymore.
658 Please report any new bugs/problems, that may be caused by this big
659 change. They will be fixed immediately.
661 The enumeration format character '%e' is deprecated and will be
662 removed sometimes from a future udev version. It never worked correctly
663 outside of udevstart, so we can't use it with the new parallel
664 coldplug. A simple enumeration is as useless as the devfs naming
665 scheme, just get rid of both if you still use it.
667 MODALIAS and $modalias is not needed and will be removed from one of
668 the next udev versions, replace it in all rules with ENV{MODALIAS} or
669 the sysfs "modalias" value.
671 Thanks a lot to Marco for all his help on finding and fixing bugs.
675 Let scsi_id request libata drive serial numbers from page 0x80.
677 Renamed etc/udev/persistent.rules to persistent-disk.rules and
678 added /dev/disk/by-name/* for device mapper device names.
680 Removed %e from the man page. It never worked reliably outside
681 of udevstart and udevstart is no longer recommended to use.
685 Symlinks are now exported to the event environment. Hopefully it's no
686 longer needed to run udevinfo from an event process, like it was
687 mentioned on the hotplug list:
688 UDEV [1134776873.702967] add@/block/sdb
691 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
695 Fix a problem if udevsend is used as the hotplug handler and tries to use
696 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
697 and this kind of problems will hopefully go away soon.
701 All built-in logic to work around bad sysfs timing is removed with this
702 version. The need to wait for sysfs files is almost fixed with a kernel
703 version that doesn't work with this udev version anyway. Until we fix
704 the timing of the "bus" link creation, the former integrated logic should
705 be emulated by a rule placed before all other rules:
706 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
708 The option "udev_db" does no longer exist. All udev state will be in
709 /$udev_root/.udev/ now, there is no longer an option to set this
711 If the init script or something else used this value, just depend on
712 this hardcoded path. But remember _all_content_ of this directory is
713 still private to udev and can change at any time.
715 Default location for rule sripts and helper programs is now: /lib/udev/.
716 Everything that is not useful on the commandline should go into this
717 directory. Some of the helpers in the extras folder are installed there
718 now. The rules need to be changed, to find the helpers there.
720 Also /lib/udev/devices is recommended as a directory where packages or
721 the user can place real device nodes, which get copied over to /dev at
722 every boot. This should replace the various solutions with custom config
725 Udevsend does no longer start the udev daemon. This must be done with
726 the init script that prepares /dev on tmpfs and creates the initial nodes,
727 before starting the daemon.
731 Silent a too verbose error logging for the old hotplug.d/ dev.d/
734 The copy of klibc is removed. A systemwide installed version of klibc
735 should be used to build a klibc udev now.
739 NAME="" will not create any nodes, but execute RUN keys. To completely
740 ignore an event the OPTION "ignore_device" should be used.
742 After removal of the reorder queue, events with a TIMEOUT can be executed
743 without any queuing now.
747 Fixed bug in udevd, if inotify is not available. We depend on netlink
748 uevents now, kernels without that event source will not work with that
749 version of udev anymore.
753 The rule parsing happens now in the daemon once at startup, all udev
754 event processes inherit the already parsed rules from the daemon.
755 It is shipped with SUSE10.0 and reduces heavily the system load at
756 startup. The option to save precompiled rules and let the udev process
757 pick the them up is removed, as it's no longer needed.
759 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
760 device. Libsysfs is changed to "translate" the requested link into the
761 real device path, as it would happen with the hotplug event. Otherwise
762 device removal and the udev database will not work.
764 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
767 A few improvements for vol_id, the filesytem probing code.
771 Fix a stupid typo in extras/run_directory for "make install".
773 scsi_id creates the temporary devnode now in /dev for usage with a
774 non-writable /tmp directory.
776 The uevent kernel socket buffer can carry app. 50.000 events now,
777 let's see who can break this again. :)
779 The upcoming kernel will have a new input driver core integration.
780 Some class devices are now symlinks to the real device. libsysfs
781 needs a fix for this to work correctly. Udevstart of older udev
782 versions will _not_ create these devices!
786 Fix a 'install' target in the Makefile, that prevents EXTRAS from
791 A bunch of mostly trivial bugfixes. From now on no node name or
792 symlink name can contain any character than plain whitelisted ascii
793 characters or validated utf8 byte-streams. This is needed for the
794 /dev/disk/by-label/* links, because we import untrusted data and
795 export it to the filesystem.
799 More bugfixes. If udevd was started from the kernel, we don't
800 have stdin/stdout/stderr, which broke the forked tools in some
805 Bugfix. udevstart event ordering was broken for a long time.
806 The new run_program() uncovered it, because /dev/null was not
807 available while we try to run external programs.
808 Now udevstart should create it before we run anything.
812 Minor bugfixes and some distro rules updates. If you don't have the
813 persistent disk rules in /dev/disk/by-*/* on your distro, just
814 grab it from here. :)
818 We can use socket communication now to pass events from udev to
820 RUN+="socket:/org/freedesktop/hal/udev_event"
821 will pass the whole udev event to the HAL daemon without the need
822 for a forked helper. (See ChangeLog for udevmonitor, as an example)
826 Mostly bugfixes and see ChangeLog.
828 The test for the existence of an environment value should be
830 ENV{KEY}=="*" to ENV{KEY}=="?*"
831 because "*" will not fail anymore, if the key does not exist or
836 Bugfixes and a few tweaks described in the ChangeLog.
840 Mostly a Bugfix release.
842 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
843 timing with custom rules.
847 We changed the internal rule storage format. Our large rule files took
848 2 MB of RAM, with the change we are down to 99kB.
850 If the device-node has been created with default name and no symlink or
851 options are to remenber, it is not longer stored in the udevdb. HAL will
852 need to be updated to work correctly with that change.
854 To overrride optimization flags, OPTFLAGS may be used now.
862 Major changes happened with this release. The goal is to take over the
863 complete kernel-event handling and provide a more efficient way to dispatch
864 kernel events. Replacing most of the current shell script logic and the
865 kernel forked helper with a netlink-daemon and a rule-based event handling.
867 o udevd listens to netlink events now. The first valid netlink event
868 will make udevd ignore any message from udevsend that contains a
869 SEQNUM, to avoid duplicate events. The forked events can be disabled
871 echo "" > /proc/sys/kernel/hotplug
872 For full support, the broken input-subsytem needs to be fixed, not to
873 bypass the driver core.
875 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
876 removed from udev itself and must be emulated by calling small
877 helper binaries provided in the extras folder:
878 make EXTRAS=extras/run_directory/
879 will build udev_run_devd and udev_run_hotplugd, which can be called
880 from a rule if needed:
881 RUN+="/sbin/udev_run_hotplugd"
882 The recommended way to handle this is to convert all the calls from
883 the directories to explicit udev rules and get completely rid of the
884 multiplexing. (To catch a ttyUSB event, you now no longer need to
885 fork and exit 300 tty script instances you are not interested in, it
886 is just one rule that matches exactly the device.)
888 o udev handles now _all_ events not just events for class and block
889 devices, this way it is possible to control the complete event
890 behavior with udev rules. Especially useful for rules like:
891 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
893 o As used in the modalias rule, udev supports now textual
894 substitution placeholder along with the usual format chars. This
895 needs to be documented, for now it's only visible in udev_rules_parse.c.
897 o The rule keys support now more operations. This is documented in the
898 man page. It is possible to add values to list-keys like the SYMLINK
899 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
900 Also "final"-assignments are supported by using KEY:="value", which will
901 prevent changing the key by any later rule.
903 o kernel 2.6.12 has the "detached_state" attribute removed from
904 sysfs, which was used to recognize sysfs population. We switched that
905 to wait for the "bus" link, which is only available in kernels after 2.6.11.
906 Running this udev version on older kernels may cause a short delay for
909 o To provide infrastructure for persistent device naming, the id programs:
910 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
911 to export the probed data in environment key format:
912 pim:~ # /sbin/ata_id --export /dev/hda
913 ID_MODEL=HTS726060M9AT00
914 ID_SERIAL=MRH401M4G6UM9B
918 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
919 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
922 kay@pim:~> tree /dev/disk
925 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
926 | `-- IBM-Memory_Key -> ../../sda
928 | |-- swap -> ../../hda1
929 | |-- date -> ../../sda1
930 | `-- home -> ../../hda3
932 |-- 2E08712B0870F2E7 -> ../../hda3
933 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
934 |-- E845-7A89 -> ../../sda1
935 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
937 The IMPORT= operation will import these keys in the environment and make
938 it available for later PROGRAM= and RUN= executed programs. The keys are
939 also stored in the udevdb and can be queried from there with one of the
942 o A few binaries are silently added to the repository, which can be used
943 to replay kernel events from initramfs instead of using coldplug. udevd
944 can be instructed now to queue-up events while the stored events from
945 initramfs are filled into the udevd-queue. This code is still under
946 development and there is no documentation now besides the code itself.
947 The additional binaries get compiled, but are not installed by default.
949 o There is also a temporary fix for a performance problem where too many
950 events happen in parallel and every event needs to parse the rules.
951 udev can now read precompiled rules stored on disk. This is likely to be
952 replaced by a more elegant solution in a future udev version.
956 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
957 Fix for libsysfs not to expect this file was added.
961 All rules are applied now, but only the first matching rule with a NAME-key
962 will be applied. All later rules with NAME-key are completely ignored. This
963 way system supplied symlinks or permissions gets applied to user-defined
967 Please check your rules setup, if you may need to add OPTIONS="last_rule"
968 to some rules, to keep the old behavior.
970 The rules are read on "remove"-events too. That makes is possible to match
971 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
972 instruct udev to ignore an event (OPTIONS="ignore_device").
973 The new ACTION-key may be used to let a rule act only at a "remove"-event.
975 The new RUN-key supports rule-based execution of programs after device-node
976 handling. This is meant as a general replacement for the dev.d/-directories
977 to give fine grained control over the execution of programs.
979 The %s{}-sysfs format char replacement values are searched at any of the
980 devices in the device chain now, not only at the class-device.
982 We support log priority levels now. The value udev_log in udev.conf is used
983 to determine what is printed to syslog. This makes it possible to
984 run a version with compiled-in debug messages in a production environment
985 which is sometimes needed to find a bug.
986 It is still possible to supress the inclusion of _any_ syslog usage with
987 USE_LOG=false to create the smallest possible binaries if needed.
988 The configured udev_log value can be overridden with the environment variable
993 Possible use of a system-wide klibc:
994 make USE_KLIBC=true KLCC=/usr/bin/klcc all
995 will link against an external klibc and our own version will be ignored.
999 We support an unlimited count of symlinks now.
1001 If USE_STATIC=true is passed to a glibc build, we link statically and use
1002 a built-in userdb parser to resolve user and group names.
1004 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
1005 we walk up the chain of physical devices to find a match.
1007 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
1008 easy to skip certain attribute matches without composing rules with weird
1009 character class negations like:
1010 KERNEL="[!s][!c][!d]*"
1011 this can now be replaced with:
1013 The current simple '=' is still supported, and should work as it does today,
1014 but existing rules should be converted if possible, to be better readable.
1016 We have new ENV{}== key now, to match against a maximum of 5 environment
1019 udevstart is its own binary again, because we don't need co carry this araound
1020 with every forked event.