5 The installed watch for block device metadata changes is now removed
6 during event hadling, because some (broken) tools may be called from udev
7 rules and (wrongly) open the device with write access. After the finished
8 event handling the watch is restored.
14 Device nodes can be watched for changes with inotify with OPTIONS="watch".
15 If closed after being opened for writing, a "change" uevent will occur.
16 /dev/disk/by-{label,uuid}/* symlinks will be automatically updated.
22 The udevadm test command has no longer a --force option, nodes and symlinks
23 are always updated with a test run now.
25 The udevd daemon can be started with --resolve-names=never to avoid all user
26 and group lookups (e.g. in cut-down systems) or --resolve-names=late to
27 lookup user and groups every time events are handled.
33 We are currently merging the Ubuntu rules in the udev default rules,
34 and get one step closer to provide a common Linux /dev setup, regarding
35 device names, symlinks, and default device permissions. On udev startup,
36 we now expect the following groups to be resolvable to their ids with
38 disk, cdrom, floppy, tape, audio, video, lp, tty, dialout, kmem.
39 LDAP setups need to make sure, that these groups are always resolvable at
40 bootup, with only the rootfs mounted, and without network access available.
42 Some systems may need to add some new, currently not used groups, or need
43 to add some users to new groups, but the cost of this change is minimal,
44 compared to the pain the current, rather random, differences between the
45 various distributions cause for upstream projects and third-party vendors.
47 In general, "normal" users who log into a machine should never be a member
48 of any such group, but the device-access should be managed by dynamic ACLs,
49 which get added and removed for the specific users on login/logout and
50 session activity/inactivity. These groups are only provided for custom setups,
51 and mainly system services, to allow proper privilege separation.
52 A video-streaming daemon uid would be a member of "audio" and "video", to get
53 access to the sound and video devices, but no "normal" user should ever belong
54 to the "audio" group, because he could listen to the built-in microphone with
55 any ssh-session established from the other side of the world.
57 /dev/serial/by-{id,path}/ now contains links for ttyUSB devices,
58 which do not depend on the kernel device name. As usual, unique
59 devices - only a single one per product connected, or a real
60 USB serial number in the device - are always found with the same
61 name in the by-id/ directory.
62 Completely identical devices may overwrite their names in by-id/
63 and can only be found reliably in the by-path/ directory. Devices
64 specified by by-path/ must not change their connection, like the
65 USB port number they are plugged in, to keep their name.
67 To support some advanced features, Linux 2.6.22 is the oldest supported
68 version now. The kernel config with enabled SYSFS_DEPRECATED is no longer
69 supported. Older kernels should still work, and devices nodes should be
70 reliably created, but some rules and libudev will not work correctly because
71 the old kernels do not provide the expected information or interfaces.
77 Fix for a possible segfault while swapping network interface names in udev
84 The group "video" is part of the default rules now.
88 Bugfix for kernels using SYSFS_DEPRECATED* option and finding parent
89 block devices in some cases. No common distro uses this option anymore,
90 and we do not get enough testing for this and recent udev versions. If
91 this option is not needed to run some old distro with a new kernel,
92 it should be disabled in the kernel config.
94 Bugfix for the $links substitution variable, which may crash if no links
95 are created. This should not happen in usual setups because we always
96 create /dev/{block,char}/ links.
98 The strings of the parsed rules, which are kept in memory, no longer
99 contain duplicate entries, or duplicate tails of strings. This, and the
100 new rules parsing/matching code reduces the total in-memory size of
101 a huge distro rule sets to 0.08 MB, compared to the 1.2MB of udev
104 The export of DEVTYPE=disk/partition got removed from the default
105 rules. This value is available from the kernel. The pnp shell script
106 modprobe hack is removed from the default rules. ACPI devices have _proper_
107 modalias support and take care of the same functionality.
108 Installations which support old kernels, but install current default
109 udev rules may want to add that to the compat rules file.
111 Libvolume_id now always probes for all known filesystems, and does not
112 stop at the first match. Some filesystems are marked as "exclusive probe",
113 and if any other filesytem type matches at the same time, libvolume_id
114 will, by default, not return any probing result. This is intended to prevent
115 mis-detection with conflicting left-over signatures found from earlier
116 file system formats. That way, we no longer depend on the probe-order
117 in case of multiple competing signatures. In some setups the kernel allows
118 to mount a volume with just the old filesystem signature still in place.
119 This may damage the new filesystem and cause data-loss, just by mounting
120 it. Because volume_id can not decide which one the correct signature is,
121 the wrong signatures need to be removed manually from the volume, or the
122 volume needs to be reformatted, to enable filesystem detection and possible
127 Fix segfault if compiled without optimization and dbg() does not get
128 compiled out and uses variables which are not available.
132 Bugfixes. (And maybe new bugs. :))
134 The rule matching engine got converted from a rule list to a token
135 array which reduced the in-memory rules representation of a full
136 featured distros with thousends of udev rules from 1.2MB to 0.12 MB.
137 Limits like 5 ENV and ATTR matches, and one single instance for most
138 other keys per rule are gone.
140 The NAME assignment is no longer special cased. If later rules assign
141 a NAME value again, the former value will be overwritten. As usual
142 for most other keys, the NAME value can be protected by doing a final
143 assignment with NAME:="<value>".
145 All udev code now uses libudev, which is also exported. The library
146 is still under development, marked as experimental, and its interface
147 may change as long as the DeviceKit integration is not finished.
149 Many thanks to Alan Jenkins for his continuous help, and finding and
150 optimizing some of the computing expensive parts.
156 Kernel devices and device nodes are connected now by reverse indizes in
157 /sys and /dev. A device number retrieved by a stat() or similar, the
158 kernel device directory can be found by looking up:
159 /sys/dev/{block,char}/<maj>:<min>
160 and the device node of the same device by looking up:
161 /dev/{block,char}/<maj>:<min>
165 Fix recently introduced bug, which caused a compilation without large
166 file support, where vol_id does not recognize raid signatures at the end
169 Firewire disks now create both, by-id/scsi-* and by-id/ieee-* links.
170 Seems some kernel versions prevent the creation of the ieee-* links,
171 so people used the scsi-* link which disappeared now.
173 More libudev work. Almost all udevadm functionality comes from libudev
176 udevadm trigger has a new option --type, which allows to trigger events
177 for "devices", for "subsystems", or "failed" devices. The old option
178 --retry-failed" still works, but is no longer mentioned in the man page.
184 The udevadm info --device-id-of-file= output has changed to use
185 the obvious format. Possible current users should use the --export
186 option which is not affected.
188 The old udev commands symlinks to udevadm are not installed, if
189 these symlinks are used, a warning is printed.
195 Optical drive's media is no longer probed for raid signatures,
196 reading the end of the device causes some devices to malfunction.
197 Also the offset of the last session found is used now to probe
200 The volume_id library got a major version number update to 1,
201 some deprecated functions are removed.
203 A shared library "libudev" gets installed now to provide access
204 to udev device information. DeviceKit, the successor of HAL, will
205 need this library to access the udev database and search sysfs for
207 The library is currently in an experimental state, also the API is
208 expected to change, as long as the DeviceKit integration is not
213 We use ./configure now. See INSTALL for details. Current
216 "/usr" - prefix for man pages, include files
218 "" - the root filesystem, prefix for libs and binaries
222 "lib" - directory name for libraries, not a path name
223 multilib 64bit systems may use "lib64" instead of "lib"
225 compile-in verbose debug messages
227 disable all logging and compile-out all log strings
229 link against SELInux libraries, to set the expected context
232 In the default rules, the group "disk" gets permissions 0660 instead
233 of 0640. One small step closer to unify distro rules. Some day, all
234 distros hopefully end up with the same set of rules.
236 No symlinks to udevadm are installed anymore, if they are still needed,
237 they should be provided by the package.
243 Default udev rules, which are not supposed to be edited by the user, should
244 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
245 the udev package and will be replaced with an update. Udev will pick up rule
247 /lib/udev/rules.d/ - default installed rules
248 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
249 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
250 It does not matter in which directory a rule file lives, all files are sorted
253 To help creating /dev/root, we have now:
254 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
257 In case the current --device-id-of-file is already used, please switch to
258 the --export format version, it saves the output parsing and the old
259 format will be changed to use ':' as a separator, like the format in the
264 Fix cdrom_id to properly recognize blank media.
270 Tape drive id-data is queried from /dev/bsg/* instead of the tape
271 nodes. This avoids rewinding tapes on open().
277 The symlinks udevcontrol and udevtrigger are no longer installed by
280 The scsi_id program does not depend on sysfs anymore. It can speak
281 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
282 data, which should solve some old problems with tape devices, where
283 we better do not open all tape device nodes to identify the device.
289 The cdrom_id program is replaced by an advanced version, which can
290 detect most common device types, and also properties of the inserted
291 media. This is part of moving some basic functionality from HAL into
292 udev (and the kernel).
298 The last WAIT_FOR_SYSFS rule is removed from the default rules.
300 The symlinks to udevadm for the debugging tools: udevmonitor and
301 udevtest are no longer created.
303 The symlinks to the udevadm man page for the old tool names are
306 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
307 should be prefixed with '@' to indicate that the path is not a
318 Udevstart is removed from the tree, it did not get installed for
319 a long time now, and is long replaced by trigger and settle.
325 All udev tools are merged into a single binary called udevadm.
326 The old names of the tools are built-in commands in udevadm now.
327 Symlinks to udevadm, with the names of the old tools, provide
328 the same functionality as the standalone tools. There is also
329 only a single udevadm.8 man page left for all tools.
331 Tools like mkinitramfs should be checked, if they need to include
332 udevadm in the list of files.
342 The etc/udev/rules.d/ directory now contains a default set of basic
343 udev rules. This initial version is the result of a rules file merge
344 of Fedora and openSUSE. For these both distros only a few specific
345 rules are left in their own file, named after the distro. Rules which
346 are optionally installed, because they are only valid for a specific
347 architecture, or rules for subsystems which are not always used are
348 in etc/udev/packages/.
354 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
355 actions by dynamically created rules.
357 SYMLINK=="<value>" matches agains the entries in the list of
358 currently defined symlinks. The links are not created in the
359 filesystem at that point in time, but the values can be matched.
361 RUN{ignore_error}+="<program>" will ignore any exit code from the
362 program and not record as a failed event.
368 Final merge of patches/features from the Ubuntu package.
374 Control characters in filesystem label strings are no longer silenty
375 removed, but hex-encoded, to be able to uniquely identify the device
376 by its symlink in /dev/disk/by-label/.
377 If libvolume_id is used by mount(8), LABEL= will work as expected,
378 if slashes or other characters are used in the label string.
380 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
381 can be specified now. The TEST key accepts an optional mode mask
382 TEST{0100}=="<is executable file>".
384 Scsi_id now supports a mode without expecting scsi-specific sysfs
385 entries to allow the extraction of cciss-device persistent properties.
391 In the future, we may see uuid's which are just simple character
392 strings (see the DDF Raid Specification). For that reason vol_id now
393 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
394 the creation of symlinks, the *_SAFE values ensure, that no control
395 or whitespace characters are used in the filename.
397 Possible users of libvolume_id, please use the volume_id_get_* functions.
398 The public struct will go away in a future release of the library.
404 Removal of useless extras/eventrecorder.sh.
414 The directory multiplexer for dev.d/ and hotplug.d are finally removed
415 from the udev package.
421 Symlinks can have priorities now, the priority is assigned to the device
422 and specified with OPTIONS="link_priority=100". Devices with higher
423 priorities overwrite the symlinks of devices with lower priorities.
424 If the device that currently owns the link, goes away, the symlink
425 will be removed, and recreated, pointing to the next device with the
426 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
427 more reliable, if multiple devices contain the same metadata and overwrite
430 The dasd_id program is removed from the udev tree, and dasdinfo, with the
431 needed rules, are part of the s390-tools now.
433 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
434 we may get the scsi sysfs mess fixed some day, and this will only catch
435 the devices we are looking for.
437 USB serial numbers for storage devices have the target:lun now appended,
438 to make it possibble to distinguish broken multi-lun devices with all
439 the same SCSI identifiers.
441 Note: The extra "run_directory" which searches and executes stuff in
442 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
443 with the next release. Make sure, that you don't use it anymore, or
444 provides your own implementation of that inefficient stuff.
445 We are tired of reports about a "slow udev", because these directories
446 contain stuff, that runs with _every_ event, instead of using rules,
447 that run programs only for the matching events.
457 DRIVER== will match only for devices that actually have a real
458 driver. DRIVERS== must be used, if parent devices should be
459 included in the match.
461 Libvolume_id's "linux_raid" detection needed another fix.
469 Add additional check to volume_id detection of via_raid, cause
470 some company decided to put a matching pattern all over the empty
471 storage area of their music players.
475 Fix path_id for SAS devices.
479 The udev daemon can be started with --debug-trace now, which will
480 execute all events serialized to get a chance to catch a possible
481 action that crashes the box.
483 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
484 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
485 are excluded from the warning. Referencing parent attributes directly
486 may break when something in the kernel driver model changes. Udev will
487 just find the attribute by walking up the parent chain.
489 Udevtrigger now sorts the list of devices depending on the device
490 dependency, so a "usb" device is triggered after the parent "pci"
495 Revert persistent-storage ata-serial '_' '-' replacement.
501 Udevtrigger can now filter the list of devices to be triggered. Matches
502 for subsystems or sysfs attributes can be specified.
504 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
505 zero-sized files to avoid pointing to /sys and confuse broken tools which
506 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
509 The rules and scripts to create udev rules for persistent network
510 devices and optical drives are in the extras/rules_generator directory
511 now. If you use something similar, please consider replacing your own
512 version with this, to share the support effort. The rule_generator
513 installs its own rules into /etc/udev/rules.d.
515 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
516 the rule_generator depends on cdrom_id to be called in an earlier rule.
522 Renaming of some key names (the old names still work):
523 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
524 (The behavior of the key DRIVER will change soon in one of the next
525 releases, to match only the event device, please switch to DRIVERS
526 instead. If DRIVER is used, it will behave like DRIVERS, but an error
528 With the new key names, we have a more consistent and simpler scheme.
529 We can match the properties of the event device only, with: KERNEL,
530 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
531 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
532 longer mentioned in the man page and should be switched in the rule
535 ATTR{file}="value" can be used now, to write to a sysfs file of the
536 event device. Instead of:
537 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
539 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
541 All the PHYSDEV* keys are deprecated and will be removed from a
543 PHYDEVPATH - is the path of a parent device and should not be
545 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
546 matched with SUBSYSTEMS==
547 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
548 Newer kernels will have DRIVER in the environment,
549 for older kernels udev puts in. Class device will
550 no longer carry this property of a parent and
551 DRIVERS== can be used to match such a parent value.
552 Note that ENV{DRIVER} is only available for a few bus devices, where
553 the driver is already bound at device event time. On coldplug, the
554 events for a lot devices are already bound to a driver, and they will have
555 that value set. But on hotplug, at the time the kernel creates the device,
556 it can't know what driver may claim the device after that, therefore
557 in most cases it will be empty.
559 Failed events should now be re-triggered with:
560 udevtrigger --retry-failed.
561 Please switch to this command, so we keep the details of the /dev/.udev/failed/
562 files private to the udev tools. We may need to switch the current symlink
563 target, cause some obviously broken tools try to scan all files in /dev
564 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
565 million times. This takes ages on slow boxes.
567 The udevinfo attribute walk (-a) now works with giving a device node
568 name (-n) instead of a devpath (-p). The query now always works, also when
569 no database file was created by udev.
571 The built-in /etc/passwd /etc/group parser is removed, we always depend on
572 getpwnam() and getgrnam() now. One of the next releases will depend on
573 fnmatch() and may use getopt_long().
577 Bugfixes and small improvements.
581 Fix path_id for recent kernels.
587 Added support for swapping network interface names, by temporarily
588 renaming the device and wait for the target name to become free.
592 The built-in MODALIAS key and substitution is removed.
596 The binary firmware helper is replaced by the usual simple
597 shell script. Udevsend is removed from the tree.
605 Some more keys require the correct use of '==' and '=' depending
606 on the kind of operation beeing an assignment or a match. Rules
607 with invalid operations are skipped and logged to syslog. Please
608 test with udevtest if the parsing of your rules throws errors and
609 fix possibly broken rules.
613 Provide "udevsettle" to wait for all current udev events to finish.
614 It also watches the current kernel netlink queue by comparing the
615 even sequence number to make sure that there are no current pending
616 events that have not already arrived in the daemon.
620 Fix rule to skip persistent rules for removable IDE devices, which
621 also skipped optical IDE drives.
623 All *_id program are installed in /lib/udev/ by default now.
625 No binary is stripped anymore as this should be done in the
626 packaging process and not at build time.
628 libvolume_id is provided as a shared library now and vol_id is
629 linked against it. Also one of the next HAL versions will require
630 this library, and the HAL build process will also require the
631 header file to be installed. The copy of the same code in HAL will
632 be removed to have only a single copy left on the system.
636 Add persistent links for SCSI tapes. The rules file is renamed
637 to 60-persistent-storage.rules.
639 Create persistent path for usb devices. Can be used for all sorts
640 of devices that can't be distinguished by other properties like
641 multiple identical keyboards and mice connected to the same box.
643 Provide "udevtrigger" program to request events on coldplug. The
644 shell script is much too slow with thousends of devices.
648 Fix persistent disk rules to exclude removable IDE drives.
650 Warn if %e, $modalias or MODALIAS is used.
654 Fix queue export, which wasn't correct for subsequent add/remove
655 events for the same device.
659 Fix cramfs detection on big endian.
661 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
666 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
667 attributes were only checked at the parent device that matched the
668 by BUS requested subsystem. Fix it to also look at the device we
669 received the event for.
671 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
676 Fix a bug where NAME="" would prevent RUN from beeing executed.
678 RUN="/bin/program" does not longer automatically add the subsystem
679 as the first parameter. This is from the days of /sbin/hotplug
680 which is dead now and it's just confusing to need to add a space at
681 the end of the program name to prevent this.
682 If you use rules that need the subsystem as the first parameter,
683 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
684 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
688 The udev man page has moved to udev(7) as it does not describe a command
689 anymore. The programs udev, udevstart and udevsend are no longer installed
690 by default and must be copied manually, if they should be installed or
691 included in a package.
693 Fix a bug where "ignore_device" could run earlier collected RUN keys before
694 the ignore rule was applied.
696 More preparation for future sysfs changes. usb_id and scsi_id no longer
697 depend on a magic order of devices in the /devices chain. Specific devices
698 should be requested by their subsytem.
700 This will always find the scsi parent device without depending on a specific
702 dev = sysfs_device_get(devpath);
703 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
705 The "device" link in the current sysfs layout will be automatically
706 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
707 parent in the devpath. If a device is requested by it's symlink, like all
708 class devices in the new sysfs layout will look like, it gets automatically
709 resolved and substituted with the real devpath and not the symlink path.
712 A similar logic must be applied to _all_ sysfs users, including
713 scripts, that search along parent devices in sysfs. The explicit use of
714 the "device" link must be avoided. With the future sysfs layout all
715 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
716 back to the "class" or the "bus". The layout of the parent devices in
717 /devices is not necessarily expected to be stable across kernel releases and
718 searching for parents by their subsystem should make sysfs users tolerant
719 for changed parent chains.
723 Prepare udev to work with the experimental kernel patch, that moves
724 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
726 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
727 moving the class devices to /sys/devices.
729 Thanks again to Marco for help finding a hopefully nice compromise
730 to make %b simpler and working again.
734 Complete removal of libsysfs, replaced by simple helper functions
735 which are much simpler and a bit faster. The udev daemon operatesentirely
736 on event parameters and does not use sysfs for simple rules anymore.
737 Please report any new bugs/problems, that may be caused by this big
738 change. They will be fixed immediately.
740 The enumeration format character '%e' is deprecated and will be
741 removed sometimes from a future udev version. It never worked correctly
742 outside of udevstart, so we can't use it with the new parallel
743 coldplug. A simple enumeration is as useless as the devfs naming
744 scheme, just get rid of both if you still use it.
746 MODALIAS and $modalias is not needed and will be removed from one of
747 the next udev versions, replace it in all rules with ENV{MODALIAS} or
748 the sysfs "modalias" value.
750 Thanks a lot to Marco for all his help on finding and fixing bugs.
754 Let scsi_id request libata drive serial numbers from page 0x80.
756 Renamed etc/udev/persistent.rules to persistent-disk.rules and
757 added /dev/disk/by-name/* for device mapper device names.
759 Removed %e from the man page. It never worked reliably outside
760 of udevstart and udevstart is no longer recommended to use.
764 Symlinks are now exported to the event environment. Hopefully it's no
765 longer needed to run udevinfo from an event process, like it was
766 mentioned on the hotplug list:
767 UDEV [1134776873.702967] add@/block/sdb
770 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
774 Fix a problem if udevsend is used as the hotplug handler and tries to use
775 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
776 and this kind of problems will hopefully go away soon.
780 All built-in logic to work around bad sysfs timing is removed with this
781 version. The need to wait for sysfs files is almost fixed with a kernel
782 version that doesn't work with this udev version anyway. Until we fix
783 the timing of the "bus" link creation, the former integrated logic should
784 be emulated by a rule placed before all other rules:
785 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
787 The option "udev_db" does no longer exist. All udev state will be in
788 /$udev_root/.udev/ now, there is no longer an option to set this
790 If the init script or something else used this value, just depend on
791 this hardcoded path. But remember _all_content_ of this directory is
792 still private to udev and can change at any time.
794 Default location for rule sripts and helper programs is now: /lib/udev/.
795 Everything that is not useful on the commandline should go into this
796 directory. Some of the helpers in the extras folder are installed there
797 now. The rules need to be changed, to find the helpers there.
799 Also /lib/udev/devices is recommended as a directory where packages or
800 the user can place real device nodes, which get copied over to /dev at
801 every boot. This should replace the various solutions with custom config
804 Udevsend does no longer start the udev daemon. This must be done with
805 the init script that prepares /dev on tmpfs and creates the initial nodes,
806 before starting the daemon.
810 Silent a too verbose error logging for the old hotplug.d/ dev.d/
813 The copy of klibc is removed. A systemwide installed version of klibc
814 should be used to build a klibc udev now.
818 NAME="" will not create any nodes, but execute RUN keys. To completely
819 ignore an event the OPTION "ignore_device" should be used.
821 After removal of the reorder queue, events with a TIMEOUT can be executed
822 without any queuing now.
826 Fixed bug in udevd, if inotify is not available. We depend on netlink
827 uevents now, kernels without that event source will not work with that
828 version of udev anymore.
832 The rule parsing happens now in the daemon once at startup, all udev
833 event processes inherit the already parsed rules from the daemon.
834 It is shipped with SUSE10.0 and reduces heavily the system load at
835 startup. The option to save precompiled rules and let the udev process
836 pick the them up is removed, as it's no longer needed.
838 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
839 device. Libsysfs is changed to "translate" the requested link into the
840 real device path, as it would happen with the hotplug event. Otherwise
841 device removal and the udev database will not work.
843 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
846 A few improvements for vol_id, the filesytem probing code.
850 Fix a stupid typo in extras/run_directory for "make install".
852 scsi_id creates the temporary devnode now in /dev for usage with a
853 non-writable /tmp directory.
855 The uevent kernel socket buffer can carry app. 50.000 events now,
856 let's see who can break this again. :)
858 The upcoming kernel will have a new input driver core integration.
859 Some class devices are now symlinks to the real device. libsysfs
860 needs a fix for this to work correctly. Udevstart of older udev
861 versions will _not_ create these devices!
865 Fix a 'install' target in the Makefile, that prevents EXTRAS from
870 A bunch of mostly trivial bugfixes. From now on no node name or
871 symlink name can contain any character than plain whitelisted ascii
872 characters or validated utf8 byte-streams. This is needed for the
873 /dev/disk/by-label/* links, because we import untrusted data and
874 export it to the filesystem.
878 More bugfixes. If udevd was started from the kernel, we don't
879 have stdin/stdout/stderr, which broke the forked tools in some
884 Bugfix. udevstart event ordering was broken for a long time.
885 The new run_program() uncovered it, because /dev/null was not
886 available while we try to run external programs.
887 Now udevstart should create it before we run anything.
891 Minor bugfixes and some distro rules updates. If you don't have the
892 persistent disk rules in /dev/disk/by-*/* on your distro, just
893 grab it from here. :)
897 We can use socket communication now to pass events from udev to
899 RUN+="socket:/org/freedesktop/hal/udev_event"
900 will pass the whole udev event to the HAL daemon without the need
901 for a forked helper. (See ChangeLog for udevmonitor, as an example)
905 Mostly bugfixes and see ChangeLog.
907 The test for the existence of an environment value should be
909 ENV{KEY}=="*" to ENV{KEY}=="?*"
910 because "*" will not fail anymore, if the key does not exist or
915 Bugfixes and a few tweaks described in the ChangeLog.
919 Mostly a Bugfix release.
921 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
922 timing with custom rules.
926 We changed the internal rule storage format. Our large rule files took
927 2 MB of RAM, with the change we are down to 99kB.
929 If the device-node has been created with default name and no symlink or
930 options are to remenber, it is not longer stored in the udevdb. HAL will
931 need to be updated to work correctly with that change.
933 To overrride optimization flags, OPTFLAGS may be used now.
941 Major changes happened with this release. The goal is to take over the
942 complete kernel-event handling and provide a more efficient way to dispatch
943 kernel events. Replacing most of the current shell script logic and the
944 kernel forked helper with a netlink-daemon and a rule-based event handling.
946 o udevd listens to netlink events now. The first valid netlink event
947 will make udevd ignore any message from udevsend that contains a
948 SEQNUM, to avoid duplicate events. The forked events can be disabled
950 echo "" > /proc/sys/kernel/hotplug
951 For full support, the broken input-subsytem needs to be fixed, not to
952 bypass the driver core.
954 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
955 removed from udev itself and must be emulated by calling small
956 helper binaries provided in the extras folder:
957 make EXTRAS=extras/run_directory/
958 will build udev_run_devd and udev_run_hotplugd, which can be called
959 from a rule if needed:
960 RUN+="/sbin/udev_run_hotplugd"
961 The recommended way to handle this is to convert all the calls from
962 the directories to explicit udev rules and get completely rid of the
963 multiplexing. (To catch a ttyUSB event, you now no longer need to
964 fork and exit 300 tty script instances you are not interested in, it
965 is just one rule that matches exactly the device.)
967 o udev handles now _all_ events not just events for class and block
968 devices, this way it is possible to control the complete event
969 behavior with udev rules. Especially useful for rules like:
970 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
972 o As used in the modalias rule, udev supports now textual
973 substitution placeholder along with the usual format chars. This
974 needs to be documented, for now it's only visible in udev_rules_parse.c.
976 o The rule keys support now more operations. This is documented in the
977 man page. It is possible to add values to list-keys like the SYMLINK
978 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
979 Also "final"-assignments are supported by using KEY:="value", which will
980 prevent changing the key by any later rule.
982 o kernel 2.6.12 has the "detached_state" attribute removed from
983 sysfs, which was used to recognize sysfs population. We switched that
984 to wait for the "bus" link, which is only available in kernels after 2.6.11.
985 Running this udev version on older kernels may cause a short delay for
988 o To provide infrastructure for persistent device naming, the id programs:
989 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
990 to export the probed data in environment key format:
991 pim:~ # /sbin/ata_id --export /dev/hda
992 ID_MODEL=HTS726060M9AT00
993 ID_SERIAL=MRH401M4G6UM9B
997 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
998 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
1001 kay@pim:~> tree /dev/disk
1004 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
1005 | `-- IBM-Memory_Key -> ../../sda
1007 | |-- swap -> ../../hda1
1008 | |-- date -> ../../sda1
1009 | `-- home -> ../../hda3
1011 |-- 2E08712B0870F2E7 -> ../../hda3
1012 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
1013 |-- E845-7A89 -> ../../sda1
1014 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
1016 The IMPORT= operation will import these keys in the environment and make
1017 it available for later PROGRAM= and RUN= executed programs. The keys are
1018 also stored in the udevdb and can be queried from there with one of the
1021 o A few binaries are silently added to the repository, which can be used
1022 to replay kernel events from initramfs instead of using coldplug. udevd
1023 can be instructed now to queue-up events while the stored events from
1024 initramfs are filled into the udevd-queue. This code is still under
1025 development and there is no documentation now besides the code itself.
1026 The additional binaries get compiled, but are not installed by default.
1028 o There is also a temporary fix for a performance problem where too many
1029 events happen in parallel and every event needs to parse the rules.
1030 udev can now read precompiled rules stored on disk. This is likely to be
1031 replaced by a more elegant solution in a future udev version.
1035 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
1036 Fix for libsysfs not to expect this file was added.
1040 All rules are applied now, but only the first matching rule with a NAME-key
1041 will be applied. All later rules with NAME-key are completely ignored. This
1042 way system supplied symlinks or permissions gets applied to user-defined
1046 Please check your rules setup, if you may need to add OPTIONS="last_rule"
1047 to some rules, to keep the old behavior.
1049 The rules are read on "remove"-events too. That makes is possible to match
1050 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
1051 instruct udev to ignore an event (OPTIONS="ignore_device").
1052 The new ACTION-key may be used to let a rule act only at a "remove"-event.
1054 The new RUN-key supports rule-based execution of programs after device-node
1055 handling. This is meant as a general replacement for the dev.d/-directories
1056 to give fine grained control over the execution of programs.
1058 The %s{}-sysfs format char replacement values are searched at any of the
1059 devices in the device chain now, not only at the class-device.
1061 We support log priority levels now. The value udev_log in udev.conf is used
1062 to determine what is printed to syslog. This makes it possible to
1063 run a version with compiled-in debug messages in a production environment
1064 which is sometimes needed to find a bug.
1065 It is still possible to supress the inclusion of _any_ syslog usage with
1066 USE_LOG=false to create the smallest possible binaries if needed.
1067 The configured udev_log value can be overridden with the environment variable
1072 Possible use of a system-wide klibc:
1073 make USE_KLIBC=true KLCC=/usr/bin/klcc all
1074 will link against an external klibc and our own version will be ignored.
1078 We support an unlimited count of symlinks now.
1080 If USE_STATIC=true is passed to a glibc build, we link statically and use
1081 a built-in userdb parser to resolve user and group names.
1083 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
1084 we walk up the chain of physical devices to find a match.
1086 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
1087 easy to skip certain attribute matches without composing rules with weird
1088 character class negations like:
1089 KERNEL="[!s][!c][!d]*"
1090 this can now be replaced with:
1092 The current simple '=' is still supported, and should work as it does today,
1093 but existing rules should be converted if possible, to be better readable.
1095 We have new ENV{}== key now, to match against a maximum of 5 environment
1098 udevstart is its own binary again, because we don't need co carry this araound
1099 with every forked event.
~ianmdlvl / elogind.git / blob