5 Device nodes can be watched for changes with inotify with OPTIONS="watch".
6 If closed after being opened for writing, a "change" uevent will occur.
7 /dev/disk/by-{label,uuid}/* symlinks will be automatically updated.
13 The udevadm test command has no longer a --force option, nodes and symlinks
14 are always updated with a test run now.
16 The udevd daemon can be started with --resolve-names=never to avoid all user
17 and group lookups (e.g. in cut-down systems) or --resolve-names=late to
18 lookup user and groups every time events are handled.
24 We are currently merging the Ubuntu rules in the udev default rules,
25 and get one step closer to provide a common Linux /dev setup, regarding
26 device names, symlinks, and default device permissions. On udev startup,
27 we now expect the following groups to be resolvable to their ids with
29 disk, cdrom, floppy, tape, audio, video, lp, tty, dialout, kmem.
30 LDAP setups need to make sure, that these groups are always resolvable at
31 bootup, with only the rootfs mounted, and without network access available.
33 Some systems may need to add some new, currently not used groups, or need
34 to add some users to new groups, but the cost of this change is minimal,
35 compared to the pain the current, rather random, differences between the
36 various distributions cause for upstream projects and third-party vendors.
38 In general, "normal" users who log into a machine should never be a member
39 of any such group, but the device-access should be managed by dynamic ACLs,
40 which get added and removed for the specific users on login/logout and
41 session activity/inactivity. These groups are only provided for custom setups,
42 and mainly system services, to allow proper privilege separation.
43 A video-streaming daemon uid would be a member of "audio" and "video", to get
44 access to the sound and video devices, but no "normal" user should ever belong
45 to the "audio" group, because he could listen to the built-in microphone with
46 any ssh-session established from the other side of the world.
48 /dev/serial/by-{id,path}/ now contains links for ttyUSB devices,
49 which do not depend on the kernel device name. As usual, unique
50 devices - only a single one per product connected, or a real
51 USB serial number in the device - are always found with the same
52 name in the by-id/ directory.
53 Completely identical devices may overwrite their names in by-id/
54 and can only be found reliably in the by-path/ directory. Devices
55 specified by by-path/ must not change their connection, like the
56 USB port number they are plugged in, to keep their name.
58 To support some advanced features, Linux 2.6.22 is the oldest supported
59 version now. The kernel config with enabled SYSFS_DEPRECATED is no longer
60 supported. Older kernels should still work, and devices nodes should be
61 reliably created, but some rules and libudev will not work correctly because
62 the old kernels do not provide the expected information or interfaces.
68 Fix for a possible segfault while swapping network interface names in udev
75 The group "video" is part of the default rules now.
79 Bugfix for kernels using SYSFS_DEPRECATED* option and finding parent
80 block devices in some cases. No common distro uses this option anymore,
81 and we do not get enough testing for this and recent udev versions. If
82 this option is not needed to run some old distro with a new kernel,
83 it should be disabled in the kernel config.
85 Bugfix for the $links substitution variable, which may crash if no links
86 are created. This should not happen in usual setups because we always
87 create /dev/{block,char}/ links.
89 The strings of the parsed rules, which are kept in memory, no longer
90 contain duplicate entries, or duplicate tails of strings. This, and the
91 new rules parsing/matching code reduces the total in-memory size of
92 a huge distro rule sets to 0.08 MB, compared to the 1.2MB of udev
95 The export of DEVTYPE=disk/partition got removed from the default
96 rules. This value is available from the kernel. The pnp shell script
97 modprobe hack is removed from the default rules. ACPI devices have _proper_
98 modalias support and take care of the same functionality.
99 Installations which support old kernels, but install current default
100 udev rules may want to add that to the compat rules file.
102 Libvolume_id now always probes for all known filesystems, and does not
103 stop at the first match. Some filesystems are marked as "exclusive probe",
104 and if any other filesytem type matches at the same time, libvolume_id
105 will, by default, not return any probing result. This is intended to prevent
106 mis-detection with conflicting left-over signatures found from earlier
107 file system formats. That way, we no longer depend on the probe-order
108 in case of multiple competing signatures. In some setups the kernel allows
109 to mount a volume with just the old filesystem signature still in place.
110 This may damage the new filesystem and cause data-loss, just by mounting
111 it. Because volume_id can not decide which one the correct signature is,
112 the wrong signatures need to be removed manually from the volume, or the
113 volume needs to be reformatted, to enable filesystem detection and possible
118 Fix segfault if compiled without optimization and dbg() does not get
119 compiled out and uses variables which are not available.
123 Bugfixes. (And maybe new bugs. :))
125 The rule matching engine got converted from a rule list to a token
126 array which reduced the in-memory rules representation of a full
127 featured distros with thousends of udev rules from 1.2MB to 0.12 MB.
128 Limits like 5 ENV and ATTR matches, and one single instance for most
129 other keys per rule are gone.
131 The NAME assignment is no longer special cased. If later rules assign
132 a NAME value again, the former value will be overwritten. As usual
133 for most other keys, the NAME value can be protected by doing a final
134 assignment with NAME:="<value>".
136 All udev code now uses libudev, which is also exported. The library
137 is still under development, marked as experimental, and its interface
138 may change as long as the DeviceKit integration is not finished.
140 Many thanks to Alan Jenkins for his continuous help, and finding and
141 optimizing some of the computing expensive parts.
147 Kernel devices and device nodes are connected now by reverse indizes in
148 /sys and /dev. A device number retrieved by a stat() or similar, the
149 kernel device directory can be found by looking up:
150 /sys/dev/{block,char}/<maj>:<min>
151 and the device node of the same device by looking up:
152 /dev/{block,char}/<maj>:<min>
156 Fix recently introduced bug, which caused a compilation without large
157 file support, where vol_id does not recognize raid signatures at the end
160 Firewire disks now create both, by-id/scsi-* and by-id/ieee-* links.
161 Seems some kernel versions prevent the creation of the ieee-* links,
162 so people used the scsi-* link which disappeared now.
164 More libudev work. Almost all udevadm functionality comes from libudev
167 udevadm trigger has a new option --type, which allows to trigger events
168 for "devices", for "subsystems", or "failed" devices. The old option
169 --retry-failed" still works, but is no longer mentioned in the man page.
175 The udevadm info --device-id-of-file= output has changed to use
176 the obvious format. Possible current users should use the --export
177 option which is not affected.
179 The old udev commands symlinks to udevadm are not installed, if
180 these symlinks are used, a warning is printed.
186 Optical drive's media is no longer probed for raid signatures,
187 reading the end of the device causes some devices to malfunction.
188 Also the offset of the last session found is used now to probe
191 The volume_id library got a major version number update to 1,
192 some deprecated functions are removed.
194 A shared library "libudev" gets installed now to provide access
195 to udev device information. DeviceKit, the successor of HAL, will
196 need this library to access the udev database and search sysfs for
198 The library is currently in an experimental state, also the API is
199 expected to change, as long as the DeviceKit integration is not
204 We use ./configure now. See INSTALL for details. Current
207 "/usr" - prefix for man pages, include files
209 "" - the root filesystem, prefix for libs and binaries
213 "lib" - directory name for libraries, not a path name
214 multilib 64bit systems may use "lib64" instead of "lib"
216 compile-in verbose debug messages
218 disable all logging and compile-out all log strings
220 link against SELInux libraries, to set the expected context
223 In the default rules, the group "disk" gets permissions 0660 instead
224 of 0640. One small step closer to unify distro rules. Some day, all
225 distros hopefully end up with the same set of rules.
227 No symlinks to udevadm are installed anymore, if they are still needed,
228 they should be provided by the package.
234 Default udev rules, which are not supposed to be edited by the user, should
235 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
236 the udev package and will be replaced with an update. Udev will pick up rule
238 /lib/udev/rules.d/ - default installed rules
239 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
240 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
241 It does not matter in which directory a rule file lives, all files are sorted
244 To help creating /dev/root, we have now:
245 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
248 In case the current --device-id-of-file is already used, please switch to
249 the --export format version, it saves the output parsing and the old
250 format will be changed to use ':' as a separator, like the format in the
255 Fix cdrom_id to properly recognize blank media.
261 Tape drive id-data is queried from /dev/bsg/* instead of the tape
262 nodes. This avoids rewinding tapes on open().
268 The symlinks udevcontrol and udevtrigger are no longer installed by
271 The scsi_id program does not depend on sysfs anymore. It can speak
272 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
273 data, which should solve some old problems with tape devices, where
274 we better do not open all tape device nodes to identify the device.
280 The cdrom_id program is replaced by an advanced version, which can
281 detect most common device types, and also properties of the inserted
282 media. This is part of moving some basic functionality from HAL into
283 udev (and the kernel).
289 The last WAIT_FOR_SYSFS rule is removed from the default rules.
291 The symlinks to udevadm for the debugging tools: udevmonitor and
292 udevtest are no longer created.
294 The symlinks to the udevadm man page for the old tool names are
297 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
298 should be prefixed with '@' to indicate that the path is not a
309 Udevstart is removed from the tree, it did not get installed for
310 a long time now, and is long replaced by trigger and settle.
316 All udev tools are merged into a single binary called udevadm.
317 The old names of the tools are built-in commands in udevadm now.
318 Symlinks to udevadm, with the names of the old tools, provide
319 the same functionality as the standalone tools. There is also
320 only a single udevadm.8 man page left for all tools.
322 Tools like mkinitramfs should be checked, if they need to include
323 udevadm in the list of files.
333 The etc/udev/rules.d/ directory now contains a default set of basic
334 udev rules. This initial version is the result of a rules file merge
335 of Fedora and openSUSE. For these both distros only a few specific
336 rules are left in their own file, named after the distro. Rules which
337 are optionally installed, because they are only valid for a specific
338 architecture, or rules for subsystems which are not always used are
339 in etc/udev/packages/.
345 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
346 actions by dynamically created rules.
348 SYMLINK=="<value>" matches agains the entries in the list of
349 currently defined symlinks. The links are not created in the
350 filesystem at that point in time, but the values can be matched.
352 RUN{ignore_error}+="<program>" will ignore any exit code from the
353 program and not record as a failed event.
359 Final merge of patches/features from the Ubuntu package.
365 Control characters in filesystem label strings are no longer silenty
366 removed, but hex-encoded, to be able to uniquely identify the device
367 by its symlink in /dev/disk/by-label/.
368 If libvolume_id is used by mount(8), LABEL= will work as expected,
369 if slashes or other characters are used in the label string.
371 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
372 can be specified now. The TEST key accepts an optional mode mask
373 TEST{0100}=="<is executable file>".
375 Scsi_id now supports a mode without expecting scsi-specific sysfs
376 entries to allow the extraction of cciss-device persistent properties.
382 In the future, we may see uuid's which are just simple character
383 strings (see the DDF Raid Specification). For that reason vol_id now
384 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
385 the creation of symlinks, the *_SAFE values ensure, that no control
386 or whitespace characters are used in the filename.
388 Possible users of libvolume_id, please use the volume_id_get_* functions.
389 The public struct will go away in a future release of the library.
395 Removal of useless extras/eventrecorder.sh.
405 The directory multiplexer for dev.d/ and hotplug.d are finally removed
406 from the udev package.
412 Symlinks can have priorities now, the priority is assigned to the device
413 and specified with OPTIONS="link_priority=100". Devices with higher
414 priorities overwrite the symlinks of devices with lower priorities.
415 If the device that currently owns the link, goes away, the symlink
416 will be removed, and recreated, pointing to the next device with the
417 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
418 more reliable, if multiple devices contain the same metadata and overwrite
421 The dasd_id program is removed from the udev tree, and dasdinfo, with the
422 needed rules, are part of the s390-tools now.
424 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
425 we may get the scsi sysfs mess fixed some day, and this will only catch
426 the devices we are looking for.
428 USB serial numbers for storage devices have the target:lun now appended,
429 to make it possibble to distinguish broken multi-lun devices with all
430 the same SCSI identifiers.
432 Note: The extra "run_directory" which searches and executes stuff in
433 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
434 with the next release. Make sure, that you don't use it anymore, or
435 provides your own implementation of that inefficient stuff.
436 We are tired of reports about a "slow udev", because these directories
437 contain stuff, that runs with _every_ event, instead of using rules,
438 that run programs only for the matching events.
448 DRIVER== will match only for devices that actually have a real
449 driver. DRIVERS== must be used, if parent devices should be
450 included in the match.
452 Libvolume_id's "linux_raid" detection needed another fix.
460 Add additional check to volume_id detection of via_raid, cause
461 some company decided to put a matching pattern all over the empty
462 storage area of their music players.
466 Fix path_id for SAS devices.
470 The udev daemon can be started with --debug-trace now, which will
471 execute all events serialized to get a chance to catch a possible
472 action that crashes the box.
474 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
475 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
476 are excluded from the warning. Referencing parent attributes directly
477 may break when something in the kernel driver model changes. Udev will
478 just find the attribute by walking up the parent chain.
480 Udevtrigger now sorts the list of devices depending on the device
481 dependency, so a "usb" device is triggered after the parent "pci"
486 Revert persistent-storage ata-serial '_' '-' replacement.
492 Udevtrigger can now filter the list of devices to be triggered. Matches
493 for subsystems or sysfs attributes can be specified.
495 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
496 zero-sized files to avoid pointing to /sys and confuse broken tools which
497 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
500 The rules and scripts to create udev rules for persistent network
501 devices and optical drives are in the extras/rules_generator directory
502 now. If you use something similar, please consider replacing your own
503 version with this, to share the support effort. The rule_generator
504 installs its own rules into /etc/udev/rules.d.
506 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
507 the rule_generator depends on cdrom_id to be called in an earlier rule.
513 Renaming of some key names (the old names still work):
514 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
515 (The behavior of the key DRIVER will change soon in one of the next
516 releases, to match only the event device, please switch to DRIVERS
517 instead. If DRIVER is used, it will behave like DRIVERS, but an error
519 With the new key names, we have a more consistent and simpler scheme.
520 We can match the properties of the event device only, with: KERNEL,
521 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
522 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
523 longer mentioned in the man page and should be switched in the rule
526 ATTR{file}="value" can be used now, to write to a sysfs file of the
527 event device. Instead of:
528 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
530 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
532 All the PHYSDEV* keys are deprecated and will be removed from a
534 PHYDEVPATH - is the path of a parent device and should not be
536 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
537 matched with SUBSYSTEMS==
538 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
539 Newer kernels will have DRIVER in the environment,
540 for older kernels udev puts in. Class device will
541 no longer carry this property of a parent and
542 DRIVERS== can be used to match such a parent value.
543 Note that ENV{DRIVER} is only available for a few bus devices, where
544 the driver is already bound at device event time. On coldplug, the
545 events for a lot devices are already bound to a driver, and they will have
546 that value set. But on hotplug, at the time the kernel creates the device,
547 it can't know what driver may claim the device after that, therefore
548 in most cases it will be empty.
550 Failed events should now be re-triggered with:
551 udevtrigger --retry-failed.
552 Please switch to this command, so we keep the details of the /dev/.udev/failed/
553 files private to the udev tools. We may need to switch the current symlink
554 target, cause some obviously broken tools try to scan all files in /dev
555 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
556 million times. This takes ages on slow boxes.
558 The udevinfo attribute walk (-a) now works with giving a device node
559 name (-n) instead of a devpath (-p). The query now always works, also when
560 no database file was created by udev.
562 The built-in /etc/passwd /etc/group parser is removed, we always depend on
563 getpwnam() and getgrnam() now. One of the next releases will depend on
564 fnmatch() and may use getopt_long().
568 Bugfixes and small improvements.
572 Fix path_id for recent kernels.
578 Added support for swapping network interface names, by temporarily
579 renaming the device and wait for the target name to become free.
583 The built-in MODALIAS key and substitution is removed.
587 The binary firmware helper is replaced by the usual simple
588 shell script. Udevsend is removed from the tree.
596 Some more keys require the correct use of '==' and '=' depending
597 on the kind of operation beeing an assignment or a match. Rules
598 with invalid operations are skipped and logged to syslog. Please
599 test with udevtest if the parsing of your rules throws errors and
600 fix possibly broken rules.
604 Provide "udevsettle" to wait for all current udev events to finish.
605 It also watches the current kernel netlink queue by comparing the
606 even sequence number to make sure that there are no current pending
607 events that have not already arrived in the daemon.
611 Fix rule to skip persistent rules for removable IDE devices, which
612 also skipped optical IDE drives.
614 All *_id program are installed in /lib/udev/ by default now.
616 No binary is stripped anymore as this should be done in the
617 packaging process and not at build time.
619 libvolume_id is provided as a shared library now and vol_id is
620 linked against it. Also one of the next HAL versions will require
621 this library, and the HAL build process will also require the
622 header file to be installed. The copy of the same code in HAL will
623 be removed to have only a single copy left on the system.
627 Add persistent links for SCSI tapes. The rules file is renamed
628 to 60-persistent-storage.rules.
630 Create persistent path for usb devices. Can be used for all sorts
631 of devices that can't be distinguished by other properties like
632 multiple identical keyboards and mice connected to the same box.
634 Provide "udevtrigger" program to request events on coldplug. The
635 shell script is much too slow with thousends of devices.
639 Fix persistent disk rules to exclude removable IDE drives.
641 Warn if %e, $modalias or MODALIAS is used.
645 Fix queue export, which wasn't correct for subsequent add/remove
646 events for the same device.
650 Fix cramfs detection on big endian.
652 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
657 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
658 attributes were only checked at the parent device that matched the
659 by BUS requested subsystem. Fix it to also look at the device we
660 received the event for.
662 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
667 Fix a bug where NAME="" would prevent RUN from beeing executed.
669 RUN="/bin/program" does not longer automatically add the subsystem
670 as the first parameter. This is from the days of /sbin/hotplug
671 which is dead now and it's just confusing to need to add a space at
672 the end of the program name to prevent this.
673 If you use rules that need the subsystem as the first parameter,
674 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
675 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
679 The udev man page has moved to udev(7) as it does not describe a command
680 anymore. The programs udev, udevstart and udevsend are no longer installed
681 by default and must be copied manually, if they should be installed or
682 included in a package.
684 Fix a bug where "ignore_device" could run earlier collected RUN keys before
685 the ignore rule was applied.
687 More preparation for future sysfs changes. usb_id and scsi_id no longer
688 depend on a magic order of devices in the /devices chain. Specific devices
689 should be requested by their subsytem.
691 This will always find the scsi parent device without depending on a specific
693 dev = sysfs_device_get(devpath);
694 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
696 The "device" link in the current sysfs layout will be automatically
697 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
698 parent in the devpath. If a device is requested by it's symlink, like all
699 class devices in the new sysfs layout will look like, it gets automatically
700 resolved and substituted with the real devpath and not the symlink path.
703 A similar logic must be applied to _all_ sysfs users, including
704 scripts, that search along parent devices in sysfs. The explicit use of
705 the "device" link must be avoided. With the future sysfs layout all
706 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
707 back to the "class" or the "bus". The layout of the parent devices in
708 /devices is not necessarily expected to be stable across kernel releases and
709 searching for parents by their subsystem should make sysfs users tolerant
710 for changed parent chains.
714 Prepare udev to work with the experimental kernel patch, that moves
715 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
717 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
718 moving the class devices to /sys/devices.
720 Thanks again to Marco for help finding a hopefully nice compromise
721 to make %b simpler and working again.
725 Complete removal of libsysfs, replaced by simple helper functions
726 which are much simpler and a bit faster. The udev daemon operatesentirely
727 on event parameters and does not use sysfs for simple rules anymore.
728 Please report any new bugs/problems, that may be caused by this big
729 change. They will be fixed immediately.
731 The enumeration format character '%e' is deprecated and will be
732 removed sometimes from a future udev version. It never worked correctly
733 outside of udevstart, so we can't use it with the new parallel
734 coldplug. A simple enumeration is as useless as the devfs naming
735 scheme, just get rid of both if you still use it.
737 MODALIAS and $modalias is not needed and will be removed from one of
738 the next udev versions, replace it in all rules with ENV{MODALIAS} or
739 the sysfs "modalias" value.
741 Thanks a lot to Marco for all his help on finding and fixing bugs.
745 Let scsi_id request libata drive serial numbers from page 0x80.
747 Renamed etc/udev/persistent.rules to persistent-disk.rules and
748 added /dev/disk/by-name/* for device mapper device names.
750 Removed %e from the man page. It never worked reliably outside
751 of udevstart and udevstart is no longer recommended to use.
755 Symlinks are now exported to the event environment. Hopefully it's no
756 longer needed to run udevinfo from an event process, like it was
757 mentioned on the hotplug list:
758 UDEV [1134776873.702967] add@/block/sdb
761 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
765 Fix a problem if udevsend is used as the hotplug handler and tries to use
766 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
767 and this kind of problems will hopefully go away soon.
771 All built-in logic to work around bad sysfs timing is removed with this
772 version. The need to wait for sysfs files is almost fixed with a kernel
773 version that doesn't work with this udev version anyway. Until we fix
774 the timing of the "bus" link creation, the former integrated logic should
775 be emulated by a rule placed before all other rules:
776 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
778 The option "udev_db" does no longer exist. All udev state will be in
779 /$udev_root/.udev/ now, there is no longer an option to set this
781 If the init script or something else used this value, just depend on
782 this hardcoded path. But remember _all_content_ of this directory is
783 still private to udev and can change at any time.
785 Default location for rule sripts and helper programs is now: /lib/udev/.
786 Everything that is not useful on the commandline should go into this
787 directory. Some of the helpers in the extras folder are installed there
788 now. The rules need to be changed, to find the helpers there.
790 Also /lib/udev/devices is recommended as a directory where packages or
791 the user can place real device nodes, which get copied over to /dev at
792 every boot. This should replace the various solutions with custom config
795 Udevsend does no longer start the udev daemon. This must be done with
796 the init script that prepares /dev on tmpfs and creates the initial nodes,
797 before starting the daemon.
801 Silent a too verbose error logging for the old hotplug.d/ dev.d/
804 The copy of klibc is removed. A systemwide installed version of klibc
805 should be used to build a klibc udev now.
809 NAME="" will not create any nodes, but execute RUN keys. To completely
810 ignore an event the OPTION "ignore_device" should be used.
812 After removal of the reorder queue, events with a TIMEOUT can be executed
813 without any queuing now.
817 Fixed bug in udevd, if inotify is not available. We depend on netlink
818 uevents now, kernels without that event source will not work with that
819 version of udev anymore.
823 The rule parsing happens now in the daemon once at startup, all udev
824 event processes inherit the already parsed rules from the daemon.
825 It is shipped with SUSE10.0 and reduces heavily the system load at
826 startup. The option to save precompiled rules and let the udev process
827 pick the them up is removed, as it's no longer needed.
829 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
830 device. Libsysfs is changed to "translate" the requested link into the
831 real device path, as it would happen with the hotplug event. Otherwise
832 device removal and the udev database will not work.
834 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
837 A few improvements for vol_id, the filesytem probing code.
841 Fix a stupid typo in extras/run_directory for "make install".
843 scsi_id creates the temporary devnode now in /dev for usage with a
844 non-writable /tmp directory.
846 The uevent kernel socket buffer can carry app. 50.000 events now,
847 let's see who can break this again. :)
849 The upcoming kernel will have a new input driver core integration.
850 Some class devices are now symlinks to the real device. libsysfs
851 needs a fix for this to work correctly. Udevstart of older udev
852 versions will _not_ create these devices!
856 Fix a 'install' target in the Makefile, that prevents EXTRAS from
861 A bunch of mostly trivial bugfixes. From now on no node name or
862 symlink name can contain any character than plain whitelisted ascii
863 characters or validated utf8 byte-streams. This is needed for the
864 /dev/disk/by-label/* links, because we import untrusted data and
865 export it to the filesystem.
869 More bugfixes. If udevd was started from the kernel, we don't
870 have stdin/stdout/stderr, which broke the forked tools in some
875 Bugfix. udevstart event ordering was broken for a long time.
876 The new run_program() uncovered it, because /dev/null was not
877 available while we try to run external programs.
878 Now udevstart should create it before we run anything.
882 Minor bugfixes and some distro rules updates. If you don't have the
883 persistent disk rules in /dev/disk/by-*/* on your distro, just
884 grab it from here. :)
888 We can use socket communication now to pass events from udev to
890 RUN+="socket:/org/freedesktop/hal/udev_event"
891 will pass the whole udev event to the HAL daemon without the need
892 for a forked helper. (See ChangeLog for udevmonitor, as an example)
896 Mostly bugfixes and see ChangeLog.
898 The test for the existence of an environment value should be
900 ENV{KEY}=="*" to ENV{KEY}=="?*"
901 because "*" will not fail anymore, if the key does not exist or
906 Bugfixes and a few tweaks described in the ChangeLog.
910 Mostly a Bugfix release.
912 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
913 timing with custom rules.
917 We changed the internal rule storage format. Our large rule files took
918 2 MB of RAM, with the change we are down to 99kB.
920 If the device-node has been created with default name and no symlink or
921 options are to remenber, it is not longer stored in the udevdb. HAL will
922 need to be updated to work correctly with that change.
924 To overrride optimization flags, OPTFLAGS may be used now.
932 Major changes happened with this release. The goal is to take over the
933 complete kernel-event handling and provide a more efficient way to dispatch
934 kernel events. Replacing most of the current shell script logic and the
935 kernel forked helper with a netlink-daemon and a rule-based event handling.
937 o udevd listens to netlink events now. The first valid netlink event
938 will make udevd ignore any message from udevsend that contains a
939 SEQNUM, to avoid duplicate events. The forked events can be disabled
941 echo "" > /proc/sys/kernel/hotplug
942 For full support, the broken input-subsytem needs to be fixed, not to
943 bypass the driver core.
945 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
946 removed from udev itself and must be emulated by calling small
947 helper binaries provided in the extras folder:
948 make EXTRAS=extras/run_directory/
949 will build udev_run_devd and udev_run_hotplugd, which can be called
950 from a rule if needed:
951 RUN+="/sbin/udev_run_hotplugd"
952 The recommended way to handle this is to convert all the calls from
953 the directories to explicit udev rules and get completely rid of the
954 multiplexing. (To catch a ttyUSB event, you now no longer need to
955 fork and exit 300 tty script instances you are not interested in, it
956 is just one rule that matches exactly the device.)
958 o udev handles now _all_ events not just events for class and block
959 devices, this way it is possible to control the complete event
960 behavior with udev rules. Especially useful for rules like:
961 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
963 o As used in the modalias rule, udev supports now textual
964 substitution placeholder along with the usual format chars. This
965 needs to be documented, for now it's only visible in udev_rules_parse.c.
967 o The rule keys support now more operations. This is documented in the
968 man page. It is possible to add values to list-keys like the SYMLINK
969 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
970 Also "final"-assignments are supported by using KEY:="value", which will
971 prevent changing the key by any later rule.
973 o kernel 2.6.12 has the "detached_state" attribute removed from
974 sysfs, which was used to recognize sysfs population. We switched that
975 to wait for the "bus" link, which is only available in kernels after 2.6.11.
976 Running this udev version on older kernels may cause a short delay for
979 o To provide infrastructure for persistent device naming, the id programs:
980 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
981 to export the probed data in environment key format:
982 pim:~ # /sbin/ata_id --export /dev/hda
983 ID_MODEL=HTS726060M9AT00
984 ID_SERIAL=MRH401M4G6UM9B
988 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
989 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
992 kay@pim:~> tree /dev/disk
995 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
996 | `-- IBM-Memory_Key -> ../../sda
998 | |-- swap -> ../../hda1
999 | |-- date -> ../../sda1
1000 | `-- home -> ../../hda3
1002 |-- 2E08712B0870F2E7 -> ../../hda3
1003 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
1004 |-- E845-7A89 -> ../../sda1
1005 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
1007 The IMPORT= operation will import these keys in the environment and make
1008 it available for later PROGRAM= and RUN= executed programs. The keys are
1009 also stored in the udevdb and can be queried from there with one of the
1012 o A few binaries are silently added to the repository, which can be used
1013 to replay kernel events from initramfs instead of using coldplug. udevd
1014 can be instructed now to queue-up events while the stored events from
1015 initramfs are filled into the udevd-queue. This code is still under
1016 development and there is no documentation now besides the code itself.
1017 The additional binaries get compiled, but are not installed by default.
1019 o There is also a temporary fix for a performance problem where too many
1020 events happen in parallel and every event needs to parse the rules.
1021 udev can now read precompiled rules stored on disk. This is likely to be
1022 replaced by a more elegant solution in a future udev version.
1026 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
1027 Fix for libsysfs not to expect this file was added.
1031 All rules are applied now, but only the first matching rule with a NAME-key
1032 will be applied. All later rules with NAME-key are completely ignored. This
1033 way system supplied symlinks or permissions gets applied to user-defined
1037 Please check your rules setup, if you may need to add OPTIONS="last_rule"
1038 to some rules, to keep the old behavior.
1040 The rules are read on "remove"-events too. That makes is possible to match
1041 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
1042 instruct udev to ignore an event (OPTIONS="ignore_device").
1043 The new ACTION-key may be used to let a rule act only at a "remove"-event.
1045 The new RUN-key supports rule-based execution of programs after device-node
1046 handling. This is meant as a general replacement for the dev.d/-directories
1047 to give fine grained control over the execution of programs.
1049 The %s{}-sysfs format char replacement values are searched at any of the
1050 devices in the device chain now, not only at the class-device.
1052 We support log priority levels now. The value udev_log in udev.conf is used
1053 to determine what is printed to syslog. This makes it possible to
1054 run a version with compiled-in debug messages in a production environment
1055 which is sometimes needed to find a bug.
1056 It is still possible to supress the inclusion of _any_ syslog usage with
1057 USE_LOG=false to create the smallest possible binaries if needed.
1058 The configured udev_log value can be overridden with the environment variable
1063 Possible use of a system-wide klibc:
1064 make USE_KLIBC=true KLCC=/usr/bin/klcc all
1065 will link against an external klibc and our own version will be ignored.
1069 We support an unlimited count of symlinks now.
1071 If USE_STATIC=true is passed to a glibc build, we link statically and use
1072 a built-in userdb parser to resolve user and group names.
1074 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
1075 we walk up the chain of physical devices to find a match.
1077 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
1078 easy to skip certain attribute matches without composing rules with weird
1079 character class negations like:
1080 KERNEL="[!s][!c][!d]*"
1081 this can now be replaced with:
1083 The current simple '=' is still supported, and should work as it does today,
1084 but existing rules should be converted if possible, to be better readable.
1086 We have new ENV{}== key now, to match against a maximum of 5 environment
1089 udevstart is its own binary again, because we don't need co carry this araound
1090 with every forked event.
~ianmdlvl / elogind.git / blob