5 "udevadm settle" now optionally accepts a range of events to wait for,
6 instead of waiting for "all" events.
12 The installed watch for block device metadata changes is now removed
13 during event hadling, because some (broken) tools may be called from udev
14 rules and (wrongly) open the device with write access. After the finished
15 event handling the watch is restored.
21 Device nodes can be watched for changes with inotify with OPTIONS="watch".
22 If closed after being opened for writing, a "change" uevent will occur.
23 /dev/disk/by-{label,uuid}/* symlinks will be automatically updated.
29 The udevadm test command has no longer a --force option, nodes and symlinks
30 are always updated with a test run now.
32 The udevd daemon can be started with --resolve-names=never to avoid all user
33 and group lookups (e.g. in cut-down systems) or --resolve-names=late to
34 lookup user and groups every time events are handled.
40 We are currently merging the Ubuntu rules in the udev default rules,
41 and get one step closer to provide a common Linux /dev setup, regarding
42 device names, symlinks, and default device permissions. On udev startup,
43 we now expect the following groups to be resolvable to their ids with
45 disk, cdrom, floppy, tape, audio, video, lp, tty, dialout, kmem.
46 LDAP setups need to make sure, that these groups are always resolvable at
47 bootup, with only the rootfs mounted, and without network access available.
49 Some systems may need to add some new, currently not used groups, or need
50 to add some users to new groups, but the cost of this change is minimal,
51 compared to the pain the current, rather random, differences between the
52 various distributions cause for upstream projects and third-party vendors.
54 In general, "normal" users who log into a machine should never be a member
55 of any such group, but the device-access should be managed by dynamic ACLs,
56 which get added and removed for the specific users on login/logout and
57 session activity/inactivity. These groups are only provided for custom setups,
58 and mainly system services, to allow proper privilege separation.
59 A video-streaming daemon uid would be a member of "audio" and "video", to get
60 access to the sound and video devices, but no "normal" user should ever belong
61 to the "audio" group, because he could listen to the built-in microphone with
62 any ssh-session established from the other side of the world.
64 /dev/serial/by-{id,path}/ now contains links for ttyUSB devices,
65 which do not depend on the kernel device name. As usual, unique
66 devices - only a single one per product connected, or a real
67 USB serial number in the device - are always found with the same
68 name in the by-id/ directory.
69 Completely identical devices may overwrite their names in by-id/
70 and can only be found reliably in the by-path/ directory. Devices
71 specified by by-path/ must not change their connection, like the
72 USB port number they are plugged in, to keep their name.
74 To support some advanced features, Linux 2.6.22 is the oldest supported
75 version now. The kernel config with enabled SYSFS_DEPRECATED is no longer
76 supported. Older kernels should still work, and devices nodes should be
77 reliably created, but some rules and libudev will not work correctly because
78 the old kernels do not provide the expected information or interfaces.
84 Fix for a possible segfault while swapping network interface names in udev
91 The group "video" is part of the default rules now.
95 Bugfix for kernels using SYSFS_DEPRECATED* option and finding parent
96 block devices in some cases. No common distro uses this option anymore,
97 and we do not get enough testing for this and recent udev versions. If
98 this option is not needed to run some old distro with a new kernel,
99 it should be disabled in the kernel config.
101 Bugfix for the $links substitution variable, which may crash if no links
102 are created. This should not happen in usual setups because we always
103 create /dev/{block,char}/ links.
105 The strings of the parsed rules, which are kept in memory, no longer
106 contain duplicate entries, or duplicate tails of strings. This, and the
107 new rules parsing/matching code reduces the total in-memory size of
108 a huge distro rule sets to 0.08 MB, compared to the 1.2MB of udev
111 The export of DEVTYPE=disk/partition got removed from the default
112 rules. This value is available from the kernel. The pnp shell script
113 modprobe hack is removed from the default rules. ACPI devices have _proper_
114 modalias support and take care of the same functionality.
115 Installations which support old kernels, but install current default
116 udev rules may want to add that to the compat rules file.
118 Libvolume_id now always probes for all known filesystems, and does not
119 stop at the first match. Some filesystems are marked as "exclusive probe",
120 and if any other filesytem type matches at the same time, libvolume_id
121 will, by default, not return any probing result. This is intended to prevent
122 mis-detection with conflicting left-over signatures found from earlier
123 file system formats. That way, we no longer depend on the probe-order
124 in case of multiple competing signatures. In some setups the kernel allows
125 to mount a volume with just the old filesystem signature still in place.
126 This may damage the new filesystem and cause data-loss, just by mounting
127 it. Because volume_id can not decide which one the correct signature is,
128 the wrong signatures need to be removed manually from the volume, or the
129 volume needs to be reformatted, to enable filesystem detection and possible
134 Fix segfault if compiled without optimization and dbg() does not get
135 compiled out and uses variables which are not available.
139 Bugfixes. (And maybe new bugs. :))
141 The rule matching engine got converted from a rule list to a token
142 array which reduced the in-memory rules representation of a full
143 featured distros with thousends of udev rules from 1.2MB to 0.12 MB.
144 Limits like 5 ENV and ATTR matches, and one single instance for most
145 other keys per rule are gone.
147 The NAME assignment is no longer special cased. If later rules assign
148 a NAME value again, the former value will be overwritten. As usual
149 for most other keys, the NAME value can be protected by doing a final
150 assignment with NAME:="<value>".
152 All udev code now uses libudev, which is also exported. The library
153 is still under development, marked as experimental, and its interface
154 may change as long as the DeviceKit integration is not finished.
156 Many thanks to Alan Jenkins for his continuous help, and finding and
157 optimizing some of the computing expensive parts.
163 Kernel devices and device nodes are connected now by reverse indizes in
164 /sys and /dev. A device number retrieved by a stat() or similar, the
165 kernel device directory can be found by looking up:
166 /sys/dev/{block,char}/<maj>:<min>
167 and the device node of the same device by looking up:
168 /dev/{block,char}/<maj>:<min>
172 Fix recently introduced bug, which caused a compilation without large
173 file support, where vol_id does not recognize raid signatures at the end
176 Firewire disks now create both, by-id/scsi-* and by-id/ieee-* links.
177 Seems some kernel versions prevent the creation of the ieee-* links,
178 so people used the scsi-* link which disappeared now.
180 More libudev work. Almost all udevadm functionality comes from libudev
183 udevadm trigger has a new option --type, which allows to trigger events
184 for "devices", for "subsystems", or "failed" devices. The old option
185 --retry-failed" still works, but is no longer mentioned in the man page.
191 The udevadm info --device-id-of-file= output has changed to use
192 the obvious format. Possible current users should use the --export
193 option which is not affected.
195 The old udev commands symlinks to udevadm are not installed, if
196 these symlinks are used, a warning is printed.
202 Optical drive's media is no longer probed for raid signatures,
203 reading the end of the device causes some devices to malfunction.
204 Also the offset of the last session found is used now to probe
207 The volume_id library got a major version number update to 1,
208 some deprecated functions are removed.
210 A shared library "libudev" gets installed now to provide access
211 to udev device information. DeviceKit, the successor of HAL, will
212 need this library to access the udev database and search sysfs for
214 The library is currently in an experimental state, also the API is
215 expected to change, as long as the DeviceKit integration is not
220 We use ./configure now. See INSTALL for details. Current
223 "/usr" - prefix for man pages, include files
225 "" - the root filesystem, prefix for libs and binaries
229 "lib" - directory name for libraries, not a path name
230 multilib 64bit systems may use "lib64" instead of "lib"
232 compile-in verbose debug messages
234 disable all logging and compile-out all log strings
236 link against SELInux libraries, to set the expected context
239 In the default rules, the group "disk" gets permissions 0660 instead
240 of 0640. One small step closer to unify distro rules. Some day, all
241 distros hopefully end up with the same set of rules.
243 No symlinks to udevadm are installed anymore, if they are still needed,
244 they should be provided by the package.
250 Default udev rules, which are not supposed to be edited by the user, should
251 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
252 the udev package and will be replaced with an update. Udev will pick up rule
254 /lib/udev/rules.d/ - default installed rules
255 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
256 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
257 It does not matter in which directory a rule file lives, all files are sorted
260 To help creating /dev/root, we have now:
261 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
264 In case the current --device-id-of-file is already used, please switch to
265 the --export format version, it saves the output parsing and the old
266 format will be changed to use ':' as a separator, like the format in the
271 Fix cdrom_id to properly recognize blank media.
277 Tape drive id-data is queried from /dev/bsg/* instead of the tape
278 nodes. This avoids rewinding tapes on open().
284 The symlinks udevcontrol and udevtrigger are no longer installed by
287 The scsi_id program does not depend on sysfs anymore. It can speak
288 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
289 data, which should solve some old problems with tape devices, where
290 we better do not open all tape device nodes to identify the device.
296 The cdrom_id program is replaced by an advanced version, which can
297 detect most common device types, and also properties of the inserted
298 media. This is part of moving some basic functionality from HAL into
299 udev (and the kernel).
305 The last WAIT_FOR_SYSFS rule is removed from the default rules.
307 The symlinks to udevadm for the debugging tools: udevmonitor and
308 udevtest are no longer created.
310 The symlinks to the udevadm man page for the old tool names are
313 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
314 should be prefixed with '@' to indicate that the path is not a
325 Udevstart is removed from the tree, it did not get installed for
326 a long time now, and is long replaced by trigger and settle.
332 All udev tools are merged into a single binary called udevadm.
333 The old names of the tools are built-in commands in udevadm now.
334 Symlinks to udevadm, with the names of the old tools, provide
335 the same functionality as the standalone tools. There is also
336 only a single udevadm.8 man page left for all tools.
338 Tools like mkinitramfs should be checked, if they need to include
339 udevadm in the list of files.
349 The etc/udev/rules.d/ directory now contains a default set of basic
350 udev rules. This initial version is the result of a rules file merge
351 of Fedora and openSUSE. For these both distros only a few specific
352 rules are left in their own file, named after the distro. Rules which
353 are optionally installed, because they are only valid for a specific
354 architecture, or rules for subsystems which are not always used are
355 in etc/udev/packages/.
361 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
362 actions by dynamically created rules.
364 SYMLINK=="<value>" matches agains the entries in the list of
365 currently defined symlinks. The links are not created in the
366 filesystem at that point in time, but the values can be matched.
368 RUN{ignore_error}+="<program>" will ignore any exit code from the
369 program and not record as a failed event.
375 Final merge of patches/features from the Ubuntu package.
381 Control characters in filesystem label strings are no longer silenty
382 removed, but hex-encoded, to be able to uniquely identify the device
383 by its symlink in /dev/disk/by-label/.
384 If libvolume_id is used by mount(8), LABEL= will work as expected,
385 if slashes or other characters are used in the label string.
387 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
388 can be specified now. The TEST key accepts an optional mode mask
389 TEST{0100}=="<is executable file>".
391 Scsi_id now supports a mode without expecting scsi-specific sysfs
392 entries to allow the extraction of cciss-device persistent properties.
398 In the future, we may see uuid's which are just simple character
399 strings (see the DDF Raid Specification). For that reason vol_id now
400 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
401 the creation of symlinks, the *_SAFE values ensure, that no control
402 or whitespace characters are used in the filename.
404 Possible users of libvolume_id, please use the volume_id_get_* functions.
405 The public struct will go away in a future release of the library.
411 Removal of useless extras/eventrecorder.sh.
421 The directory multiplexer for dev.d/ and hotplug.d are finally removed
422 from the udev package.
428 Symlinks can have priorities now, the priority is assigned to the device
429 and specified with OPTIONS="link_priority=100". Devices with higher
430 priorities overwrite the symlinks of devices with lower priorities.
431 If the device that currently owns the link, goes away, the symlink
432 will be removed, and recreated, pointing to the next device with the
433 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
434 more reliable, if multiple devices contain the same metadata and overwrite
437 The dasd_id program is removed from the udev tree, and dasdinfo, with the
438 needed rules, are part of the s390-tools now.
440 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
441 we may get the scsi sysfs mess fixed some day, and this will only catch
442 the devices we are looking for.
444 USB serial numbers for storage devices have the target:lun now appended,
445 to make it possibble to distinguish broken multi-lun devices with all
446 the same SCSI identifiers.
448 Note: The extra "run_directory" which searches and executes stuff in
449 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
450 with the next release. Make sure, that you don't use it anymore, or
451 provides your own implementation of that inefficient stuff.
452 We are tired of reports about a "slow udev", because these directories
453 contain stuff, that runs with _every_ event, instead of using rules,
454 that run programs only for the matching events.
464 DRIVER== will match only for devices that actually have a real
465 driver. DRIVERS== must be used, if parent devices should be
466 included in the match.
468 Libvolume_id's "linux_raid" detection needed another fix.
476 Add additional check to volume_id detection of via_raid, cause
477 some company decided to put a matching pattern all over the empty
478 storage area of their music players.
482 Fix path_id for SAS devices.
486 The udev daemon can be started with --debug-trace now, which will
487 execute all events serialized to get a chance to catch a possible
488 action that crashes the box.
490 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
491 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
492 are excluded from the warning. Referencing parent attributes directly
493 may break when something in the kernel driver model changes. Udev will
494 just find the attribute by walking up the parent chain.
496 Udevtrigger now sorts the list of devices depending on the device
497 dependency, so a "usb" device is triggered after the parent "pci"
502 Revert persistent-storage ata-serial '_' '-' replacement.
508 Udevtrigger can now filter the list of devices to be triggered. Matches
509 for subsystems or sysfs attributes can be specified.
511 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
512 zero-sized files to avoid pointing to /sys and confuse broken tools which
513 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
516 The rules and scripts to create udev rules for persistent network
517 devices and optical drives are in the extras/rules_generator directory
518 now. If you use something similar, please consider replacing your own
519 version with this, to share the support effort. The rule_generator
520 installs its own rules into /etc/udev/rules.d.
522 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
523 the rule_generator depends on cdrom_id to be called in an earlier rule.
529 Renaming of some key names (the old names still work):
530 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
531 (The behavior of the key DRIVER will change soon in one of the next
532 releases, to match only the event device, please switch to DRIVERS
533 instead. If DRIVER is used, it will behave like DRIVERS, but an error
535 With the new key names, we have a more consistent and simpler scheme.
536 We can match the properties of the event device only, with: KERNEL,
537 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
538 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
539 longer mentioned in the man page and should be switched in the rule
542 ATTR{file}="value" can be used now, to write to a sysfs file of the
543 event device. Instead of:
544 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
546 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
548 All the PHYSDEV* keys are deprecated and will be removed from a
550 PHYDEVPATH - is the path of a parent device and should not be
552 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
553 matched with SUBSYSTEMS==
554 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
555 Newer kernels will have DRIVER in the environment,
556 for older kernels udev puts in. Class device will
557 no longer carry this property of a parent and
558 DRIVERS== can be used to match such a parent value.
559 Note that ENV{DRIVER} is only available for a few bus devices, where
560 the driver is already bound at device event time. On coldplug, the
561 events for a lot devices are already bound to a driver, and they will have
562 that value set. But on hotplug, at the time the kernel creates the device,
563 it can't know what driver may claim the device after that, therefore
564 in most cases it will be empty.
566 Failed events should now be re-triggered with:
567 udevtrigger --retry-failed.
568 Please switch to this command, so we keep the details of the /dev/.udev/failed/
569 files private to the udev tools. We may need to switch the current symlink
570 target, cause some obviously broken tools try to scan all files in /dev
571 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
572 million times. This takes ages on slow boxes.
574 The udevinfo attribute walk (-a) now works with giving a device node
575 name (-n) instead of a devpath (-p). The query now always works, also when
576 no database file was created by udev.
578 The built-in /etc/passwd /etc/group parser is removed, we always depend on
579 getpwnam() and getgrnam() now. One of the next releases will depend on
580 fnmatch() and may use getopt_long().
584 Bugfixes and small improvements.
588 Fix path_id for recent kernels.
594 Added support for swapping network interface names, by temporarily
595 renaming the device and wait for the target name to become free.
599 The built-in MODALIAS key and substitution is removed.
603 The binary firmware helper is replaced by the usual simple
604 shell script. Udevsend is removed from the tree.
612 Some more keys require the correct use of '==' and '=' depending
613 on the kind of operation beeing an assignment or a match. Rules
614 with invalid operations are skipped and logged to syslog. Please
615 test with udevtest if the parsing of your rules throws errors and
616 fix possibly broken rules.
620 Provide "udevsettle" to wait for all current udev events to finish.
621 It also watches the current kernel netlink queue by comparing the
622 even sequence number to make sure that there are no current pending
623 events that have not already arrived in the daemon.
627 Fix rule to skip persistent rules for removable IDE devices, which
628 also skipped optical IDE drives.
630 All *_id program are installed in /lib/udev/ by default now.
632 No binary is stripped anymore as this should be done in the
633 packaging process and not at build time.
635 libvolume_id is provided as a shared library now and vol_id is
636 linked against it. Also one of the next HAL versions will require
637 this library, and the HAL build process will also require the
638 header file to be installed. The copy of the same code in HAL will
639 be removed to have only a single copy left on the system.
643 Add persistent links for SCSI tapes. The rules file is renamed
644 to 60-persistent-storage.rules.
646 Create persistent path for usb devices. Can be used for all sorts
647 of devices that can't be distinguished by other properties like
648 multiple identical keyboards and mice connected to the same box.
650 Provide "udevtrigger" program to request events on coldplug. The
651 shell script is much too slow with thousends of devices.
655 Fix persistent disk rules to exclude removable IDE drives.
657 Warn if %e, $modalias or MODALIAS is used.
661 Fix queue export, which wasn't correct for subsequent add/remove
662 events for the same device.
666 Fix cramfs detection on big endian.
668 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
673 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
674 attributes were only checked at the parent device that matched the
675 by BUS requested subsystem. Fix it to also look at the device we
676 received the event for.
678 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
683 Fix a bug where NAME="" would prevent RUN from beeing executed.
685 RUN="/bin/program" does not longer automatically add the subsystem
686 as the first parameter. This is from the days of /sbin/hotplug
687 which is dead now and it's just confusing to need to add a space at
688 the end of the program name to prevent this.
689 If you use rules that need the subsystem as the first parameter,
690 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
691 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
695 The udev man page has moved to udev(7) as it does not describe a command
696 anymore. The programs udev, udevstart and udevsend are no longer installed
697 by default and must be copied manually, if they should be installed or
698 included in a package.
700 Fix a bug where "ignore_device" could run earlier collected RUN keys before
701 the ignore rule was applied.
703 More preparation for future sysfs changes. usb_id and scsi_id no longer
704 depend on a magic order of devices in the /devices chain. Specific devices
705 should be requested by their subsytem.
707 This will always find the scsi parent device without depending on a specific
709 dev = sysfs_device_get(devpath);
710 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
712 The "device" link in the current sysfs layout will be automatically
713 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
714 parent in the devpath. If a device is requested by it's symlink, like all
715 class devices in the new sysfs layout will look like, it gets automatically
716 resolved and substituted with the real devpath and not the symlink path.
719 A similar logic must be applied to _all_ sysfs users, including
720 scripts, that search along parent devices in sysfs. The explicit use of
721 the "device" link must be avoided. With the future sysfs layout all
722 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
723 back to the "class" or the "bus". The layout of the parent devices in
724 /devices is not necessarily expected to be stable across kernel releases and
725 searching for parents by their subsystem should make sysfs users tolerant
726 for changed parent chains.
730 Prepare udev to work with the experimental kernel patch, that moves
731 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
733 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
734 moving the class devices to /sys/devices.
736 Thanks again to Marco for help finding a hopefully nice compromise
737 to make %b simpler and working again.
741 Complete removal of libsysfs, replaced by simple helper functions
742 which are much simpler and a bit faster. The udev daemon operatesentirely
743 on event parameters and does not use sysfs for simple rules anymore.
744 Please report any new bugs/problems, that may be caused by this big
745 change. They will be fixed immediately.
747 The enumeration format character '%e' is deprecated and will be
748 removed sometimes from a future udev version. It never worked correctly
749 outside of udevstart, so we can't use it with the new parallel
750 coldplug. A simple enumeration is as useless as the devfs naming
751 scheme, just get rid of both if you still use it.
753 MODALIAS and $modalias is not needed and will be removed from one of
754 the next udev versions, replace it in all rules with ENV{MODALIAS} or
755 the sysfs "modalias" value.
757 Thanks a lot to Marco for all his help on finding and fixing bugs.
761 Let scsi_id request libata drive serial numbers from page 0x80.
763 Renamed etc/udev/persistent.rules to persistent-disk.rules and
764 added /dev/disk/by-name/* for device mapper device names.
766 Removed %e from the man page. It never worked reliably outside
767 of udevstart and udevstart is no longer recommended to use.
771 Symlinks are now exported to the event environment. Hopefully it's no
772 longer needed to run udevinfo from an event process, like it was
773 mentioned on the hotplug list:
774 UDEV [1134776873.702967] add@/block/sdb
777 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
781 Fix a problem if udevsend is used as the hotplug handler and tries to use
782 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
783 and this kind of problems will hopefully go away soon.
787 All built-in logic to work around bad sysfs timing is removed with this
788 version. The need to wait for sysfs files is almost fixed with a kernel
789 version that doesn't work with this udev version anyway. Until we fix
790 the timing of the "bus" link creation, the former integrated logic should
791 be emulated by a rule placed before all other rules:
792 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
794 The option "udev_db" does no longer exist. All udev state will be in
795 /$udev_root/.udev/ now, there is no longer an option to set this
797 If the init script or something else used this value, just depend on
798 this hardcoded path. But remember _all_content_ of this directory is
799 still private to udev and can change at any time.
801 Default location for rule sripts and helper programs is now: /lib/udev/.
802 Everything that is not useful on the commandline should go into this
803 directory. Some of the helpers in the extras folder are installed there
804 now. The rules need to be changed, to find the helpers there.
806 Also /lib/udev/devices is recommended as a directory where packages or
807 the user can place real device nodes, which get copied over to /dev at
808 every boot. This should replace the various solutions with custom config
811 Udevsend does no longer start the udev daemon. This must be done with
812 the init script that prepares /dev on tmpfs and creates the initial nodes,
813 before starting the daemon.
817 Silent a too verbose error logging for the old hotplug.d/ dev.d/
820 The copy of klibc is removed. A systemwide installed version of klibc
821 should be used to build a klibc udev now.
825 NAME="" will not create any nodes, but execute RUN keys. To completely
826 ignore an event the OPTION "ignore_device" should be used.
828 After removal of the reorder queue, events with a TIMEOUT can be executed
829 without any queuing now.
833 Fixed bug in udevd, if inotify is not available. We depend on netlink
834 uevents now, kernels without that event source will not work with that
835 version of udev anymore.
839 The rule parsing happens now in the daemon once at startup, all udev
840 event processes inherit the already parsed rules from the daemon.
841 It is shipped with SUSE10.0 and reduces heavily the system load at
842 startup. The option to save precompiled rules and let the udev process
843 pick the them up is removed, as it's no longer needed.
845 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
846 device. Libsysfs is changed to "translate" the requested link into the
847 real device path, as it would happen with the hotplug event. Otherwise
848 device removal and the udev database will not work.
850 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
853 A few improvements for vol_id, the filesytem probing code.
857 Fix a stupid typo in extras/run_directory for "make install".
859 scsi_id creates the temporary devnode now in /dev for usage with a
860 non-writable /tmp directory.
862 The uevent kernel socket buffer can carry app. 50.000 events now,
863 let's see who can break this again. :)
865 The upcoming kernel will have a new input driver core integration.
866 Some class devices are now symlinks to the real device. libsysfs
867 needs a fix for this to work correctly. Udevstart of older udev
868 versions will _not_ create these devices!
872 Fix a 'install' target in the Makefile, that prevents EXTRAS from
877 A bunch of mostly trivial bugfixes. From now on no node name or
878 symlink name can contain any character than plain whitelisted ascii
879 characters or validated utf8 byte-streams. This is needed for the
880 /dev/disk/by-label/* links, because we import untrusted data and
881 export it to the filesystem.
885 More bugfixes. If udevd was started from the kernel, we don't
886 have stdin/stdout/stderr, which broke the forked tools in some
891 Bugfix. udevstart event ordering was broken for a long time.
892 The new run_program() uncovered it, because /dev/null was not
893 available while we try to run external programs.
894 Now udevstart should create it before we run anything.
898 Minor bugfixes and some distro rules updates. If you don't have the
899 persistent disk rules in /dev/disk/by-*/* on your distro, just
900 grab it from here. :)
904 We can use socket communication now to pass events from udev to
906 RUN+="socket:/org/freedesktop/hal/udev_event"
907 will pass the whole udev event to the HAL daemon without the need
908 for a forked helper. (See ChangeLog for udevmonitor, as an example)
912 Mostly bugfixes and see ChangeLog.
914 The test for the existence of an environment value should be
916 ENV{KEY}=="*" to ENV{KEY}=="?*"
917 because "*" will not fail anymore, if the key does not exist or
922 Bugfixes and a few tweaks described in the ChangeLog.
926 Mostly a Bugfix release.
928 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
929 timing with custom rules.
933 We changed the internal rule storage format. Our large rule files took
934 2 MB of RAM, with the change we are down to 99kB.
936 If the device-node has been created with default name and no symlink or
937 options are to remenber, it is not longer stored in the udevdb. HAL will
938 need to be updated to work correctly with that change.
940 To overrride optimization flags, OPTFLAGS may be used now.
948 Major changes happened with this release. The goal is to take over the
949 complete kernel-event handling and provide a more efficient way to dispatch
950 kernel events. Replacing most of the current shell script logic and the
951 kernel forked helper with a netlink-daemon and a rule-based event handling.
953 o udevd listens to netlink events now. The first valid netlink event
954 will make udevd ignore any message from udevsend that contains a
955 SEQNUM, to avoid duplicate events. The forked events can be disabled
957 echo "" > /proc/sys/kernel/hotplug
958 For full support, the broken input-subsytem needs to be fixed, not to
959 bypass the driver core.
961 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
962 removed from udev itself and must be emulated by calling small
963 helper binaries provided in the extras folder:
964 make EXTRAS=extras/run_directory/
965 will build udev_run_devd and udev_run_hotplugd, which can be called
966 from a rule if needed:
967 RUN+="/sbin/udev_run_hotplugd"
968 The recommended way to handle this is to convert all the calls from
969 the directories to explicit udev rules and get completely rid of the
970 multiplexing. (To catch a ttyUSB event, you now no longer need to
971 fork and exit 300 tty script instances you are not interested in, it
972 is just one rule that matches exactly the device.)
974 o udev handles now _all_ events not just events for class and block
975 devices, this way it is possible to control the complete event
976 behavior with udev rules. Especially useful for rules like:
977 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
979 o As used in the modalias rule, udev supports now textual
980 substitution placeholder along with the usual format chars. This
981 needs to be documented, for now it's only visible in udev_rules_parse.c.
983 o The rule keys support now more operations. This is documented in the
984 man page. It is possible to add values to list-keys like the SYMLINK
985 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
986 Also "final"-assignments are supported by using KEY:="value", which will
987 prevent changing the key by any later rule.
989 o kernel 2.6.12 has the "detached_state" attribute removed from
990 sysfs, which was used to recognize sysfs population. We switched that
991 to wait for the "bus" link, which is only available in kernels after 2.6.11.
992 Running this udev version on older kernels may cause a short delay for
995 o To provide infrastructure for persistent device naming, the id programs:
996 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
997 to export the probed data in environment key format:
998 pim:~ # /sbin/ata_id --export /dev/hda
999 ID_MODEL=HTS726060M9AT00
1000 ID_SERIAL=MRH401M4G6UM9B
1001 ID_REVISION=MH4OA6BA
1003 The following rules:
1004 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
1005 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
1008 kay@pim:~> tree /dev/disk
1011 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
1012 | `-- IBM-Memory_Key -> ../../sda
1014 | |-- swap -> ../../hda1
1015 | |-- date -> ../../sda1
1016 | `-- home -> ../../hda3
1018 |-- 2E08712B0870F2E7 -> ../../hda3
1019 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
1020 |-- E845-7A89 -> ../../sda1
1021 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
1023 The IMPORT= operation will import these keys in the environment and make
1024 it available for later PROGRAM= and RUN= executed programs. The keys are
1025 also stored in the udevdb and can be queried from there with one of the
1028 o A few binaries are silently added to the repository, which can be used
1029 to replay kernel events from initramfs instead of using coldplug. udevd
1030 can be instructed now to queue-up events while the stored events from
1031 initramfs are filled into the udevd-queue. This code is still under
1032 development and there is no documentation now besides the code itself.
1033 The additional binaries get compiled, but are not installed by default.
1035 o There is also a temporary fix for a performance problem where too many
1036 events happen in parallel and every event needs to parse the rules.
1037 udev can now read precompiled rules stored on disk. This is likely to be
1038 replaced by a more elegant solution in a future udev version.
1042 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
1043 Fix for libsysfs not to expect this file was added.
1047 All rules are applied now, but only the first matching rule with a NAME-key
1048 will be applied. All later rules with NAME-key are completely ignored. This
1049 way system supplied symlinks or permissions gets applied to user-defined
1053 Please check your rules setup, if you may need to add OPTIONS="last_rule"
1054 to some rules, to keep the old behavior.
1056 The rules are read on "remove"-events too. That makes is possible to match
1057 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
1058 instruct udev to ignore an event (OPTIONS="ignore_device").
1059 The new ACTION-key may be used to let a rule act only at a "remove"-event.
1061 The new RUN-key supports rule-based execution of programs after device-node
1062 handling. This is meant as a general replacement for the dev.d/-directories
1063 to give fine grained control over the execution of programs.
1065 The %s{}-sysfs format char replacement values are searched at any of the
1066 devices in the device chain now, not only at the class-device.
1068 We support log priority levels now. The value udev_log in udev.conf is used
1069 to determine what is printed to syslog. This makes it possible to
1070 run a version with compiled-in debug messages in a production environment
1071 which is sometimes needed to find a bug.
1072 It is still possible to supress the inclusion of _any_ syslog usage with
1073 USE_LOG=false to create the smallest possible binaries if needed.
1074 The configured udev_log value can be overridden with the environment variable
1079 Possible use of a system-wide klibc:
1080 make USE_KLIBC=true KLCC=/usr/bin/klcc all
1081 will link against an external klibc and our own version will be ignored.
1085 We support an unlimited count of symlinks now.
1087 If USE_STATIC=true is passed to a glibc build, we link statically and use
1088 a built-in userdb parser to resolve user and group names.
1090 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
1091 we walk up the chain of physical devices to find a match.
1093 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
1094 easy to skip certain attribute matches without composing rules with weird
1095 character class negations like:
1096 KERNEL="[!s][!c][!d]*"
1097 this can now be replaced with:
1099 The current simple '=' is still supported, and should work as it does today,
1100 but existing rules should be converted if possible, to be better readable.
1102 We have new ENV{}== key now, to match against a maximum of 5 environment
1105 udevstart is its own binary again, because we don't need co carry this araound
1106 with every forked event.
~ianmdlvl / elogind.git / blob