9 Device nodes can be watched for changes with inotify with OPTIONS="watch".
10 If closed after being opened for writing, a "change" uevent will occur.
11 /dev/disk/by-{label,uuid}/* symlinks will be automatically updated.
17 The udevadm test command has no longer a --force option, nodes and symlinks
18 are always updated with a test run now.
20 The udevd daemon can be started with --resolve-names=never to avoid all user
21 and group lookups (e.g. in cut-down systems) or --resolve-names=late to
22 lookup user and groups every time events are handled.
28 We are currently merging the Ubuntu rules in the udev default rules,
29 and get one step closer to provide a common Linux /dev setup, regarding
30 device names, symlinks, and default device permissions. On udev startup,
31 we now expect the following groups to be resolvable to their ids with
33 disk, cdrom, floppy, tape, audio, video, lp, tty, dialout, kmem.
34 LDAP setups need to make sure, that these groups are always resolvable at
35 bootup, with only the rootfs mounted, and without network access available.
37 Some systems may need to add some new, currently not used groups, or need
38 to add some users to new groups, but the cost of this change is minimal,
39 compared to the pain the current, rather random, differences between the
40 various distributions cause for upstream projects and third-party vendors.
42 In general, "normal" users who log into a machine should never be a member
43 of any such group, but the device-access should be managed by dynamic ACLs,
44 which get added and removed for the specific users on login/logout and
45 session activity/inactivity. These groups are only provided for custom setups,
46 and mainly system services, to allow proper privilege separation.
47 A video-streaming daemon uid would be a member of "audio" and "video", to get
48 access to the sound and video devices, but no "normal" user should ever belong
49 to the "audio" group, because he could listen to the built-in microphone with
50 any ssh-session established from the other side of the world.
52 /dev/serial/by-{id,path}/ now contains links for ttyUSB devices,
53 which do not depend on the kernel device name. As usual, unique
54 devices - only a single one per product connected, or a real
55 USB serial number in the device - are always found with the same
56 name in the by-id/ directory.
57 Completely identical devices may overwrite their names in by-id/
58 and can only be found reliably in the by-path/ directory. Devices
59 specified by by-path/ must not change their connection, like the
60 USB port number they are plugged in, to keep their name.
62 To support some advanced features, Linux 2.6.22 is the oldest supported
63 version now. The kernel config with enabled SYSFS_DEPRECATED is no longer
64 supported. Older kernels should still work, and devices nodes should be
65 reliably created, but some rules and libudev will not work correctly because
66 the old kernels do not provide the expected information or interfaces.
72 Fix for a possible segfault while swapping network interface names in udev
79 The group "video" is part of the default rules now.
83 Bugfix for kernels using SYSFS_DEPRECATED* option and finding parent
84 block devices in some cases. No common distro uses this option anymore,
85 and we do not get enough testing for this and recent udev versions. If
86 this option is not needed to run some old distro with a new kernel,
87 it should be disabled in the kernel config.
89 Bugfix for the $links substitution variable, which may crash if no links
90 are created. This should not happen in usual setups because we always
91 create /dev/{block,char}/ links.
93 The strings of the parsed rules, which are kept in memory, no longer
94 contain duplicate entries, or duplicate tails of strings. This, and the
95 new rules parsing/matching code reduces the total in-memory size of
96 a huge distro rule sets to 0.08 MB, compared to the 1.2MB of udev
99 The export of DEVTYPE=disk/partition got removed from the default
100 rules. This value is available from the kernel. The pnp shell script
101 modprobe hack is removed from the default rules. ACPI devices have _proper_
102 modalias support and take care of the same functionality.
103 Installations which support old kernels, but install current default
104 udev rules may want to add that to the compat rules file.
106 Libvolume_id now always probes for all known filesystems, and does not
107 stop at the first match. Some filesystems are marked as "exclusive probe",
108 and if any other filesytem type matches at the same time, libvolume_id
109 will, by default, not return any probing result. This is intended to prevent
110 mis-detection with conflicting left-over signatures found from earlier
111 file system formats. That way, we no longer depend on the probe-order
112 in case of multiple competing signatures. In some setups the kernel allows
113 to mount a volume with just the old filesystem signature still in place.
114 This may damage the new filesystem and cause data-loss, just by mounting
115 it. Because volume_id can not decide which one the correct signature is,
116 the wrong signatures need to be removed manually from the volume, or the
117 volume needs to be reformatted, to enable filesystem detection and possible
122 Fix segfault if compiled without optimization and dbg() does not get
123 compiled out and uses variables which are not available.
127 Bugfixes. (And maybe new bugs. :))
129 The rule matching engine got converted from a rule list to a token
130 array which reduced the in-memory rules representation of a full
131 featured distros with thousends of udev rules from 1.2MB to 0.12 MB.
132 Limits like 5 ENV and ATTR matches, and one single instance for most
133 other keys per rule are gone.
135 The NAME assignment is no longer special cased. If later rules assign
136 a NAME value again, the former value will be overwritten. As usual
137 for most other keys, the NAME value can be protected by doing a final
138 assignment with NAME:="<value>".
140 All udev code now uses libudev, which is also exported. The library
141 is still under development, marked as experimental, and its interface
142 may change as long as the DeviceKit integration is not finished.
144 Many thanks to Alan Jenkins for his continuous help, and finding and
145 optimizing some of the computing expensive parts.
151 Kernel devices and device nodes are connected now by reverse indizes in
152 /sys and /dev. A device number retrieved by a stat() or similar, the
153 kernel device directory can be found by looking up:
154 /sys/dev/{block,char}/<maj>:<min>
155 and the device node of the same device by looking up:
156 /dev/{block,char}/<maj>:<min>
160 Fix recently introduced bug, which caused a compilation without large
161 file support, where vol_id does not recognize raid signatures at the end
164 Firewire disks now create both, by-id/scsi-* and by-id/ieee-* links.
165 Seems some kernel versions prevent the creation of the ieee-* links,
166 so people used the scsi-* link which disappeared now.
168 More libudev work. Almost all udevadm functionality comes from libudev
171 udevadm trigger has a new option --type, which allows to trigger events
172 for "devices", for "subsystems", or "failed" devices. The old option
173 --retry-failed" still works, but is no longer mentioned in the man page.
179 The udevadm info --device-id-of-file= output has changed to use
180 the obvious format. Possible current users should use the --export
181 option which is not affected.
183 The old udev commands symlinks to udevadm are not installed, if
184 these symlinks are used, a warning is printed.
190 Optical drive's media is no longer probed for raid signatures,
191 reading the end of the device causes some devices to malfunction.
192 Also the offset of the last session found is used now to probe
195 The volume_id library got a major version number update to 1,
196 some deprecated functions are removed.
198 A shared library "libudev" gets installed now to provide access
199 to udev device information. DeviceKit, the successor of HAL, will
200 need this library to access the udev database and search sysfs for
202 The library is currently in an experimental state, also the API is
203 expected to change, as long as the DeviceKit integration is not
208 We use ./configure now. See INSTALL for details. Current
211 "/usr" - prefix for man pages, include files
213 "" - the root filesystem, prefix for libs and binaries
217 "lib" - directory name for libraries, not a path name
218 multilib 64bit systems may use "lib64" instead of "lib"
220 compile-in verbose debug messages
222 disable all logging and compile-out all log strings
224 link against SELInux libraries, to set the expected context
227 In the default rules, the group "disk" gets permissions 0660 instead
228 of 0640. One small step closer to unify distro rules. Some day, all
229 distros hopefully end up with the same set of rules.
231 No symlinks to udevadm are installed anymore, if they are still needed,
232 they should be provided by the package.
238 Default udev rules, which are not supposed to be edited by the user, should
239 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
240 the udev package and will be replaced with an update. Udev will pick up rule
242 /lib/udev/rules.d/ - default installed rules
243 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
244 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
245 It does not matter in which directory a rule file lives, all files are sorted
248 To help creating /dev/root, we have now:
249 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
252 In case the current --device-id-of-file is already used, please switch to
253 the --export format version, it saves the output parsing and the old
254 format will be changed to use ':' as a separator, like the format in the
259 Fix cdrom_id to properly recognize blank media.
265 Tape drive id-data is queried from /dev/bsg/* instead of the tape
266 nodes. This avoids rewinding tapes on open().
272 The symlinks udevcontrol and udevtrigger are no longer installed by
275 The scsi_id program does not depend on sysfs anymore. It can speak
276 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
277 data, which should solve some old problems with tape devices, where
278 we better do not open all tape device nodes to identify the device.
284 The cdrom_id program is replaced by an advanced version, which can
285 detect most common device types, and also properties of the inserted
286 media. This is part of moving some basic functionality from HAL into
287 udev (and the kernel).
293 The last WAIT_FOR_SYSFS rule is removed from the default rules.
295 The symlinks to udevadm for the debugging tools: udevmonitor and
296 udevtest are no longer created.
298 The symlinks to the udevadm man page for the old tool names are
301 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
302 should be prefixed with '@' to indicate that the path is not a
313 Udevstart is removed from the tree, it did not get installed for
314 a long time now, and is long replaced by trigger and settle.
320 All udev tools are merged into a single binary called udevadm.
321 The old names of the tools are built-in commands in udevadm now.
322 Symlinks to udevadm, with the names of the old tools, provide
323 the same functionality as the standalone tools. There is also
324 only a single udevadm.8 man page left for all tools.
326 Tools like mkinitramfs should be checked, if they need to include
327 udevadm in the list of files.
337 The etc/udev/rules.d/ directory now contains a default set of basic
338 udev rules. This initial version is the result of a rules file merge
339 of Fedora and openSUSE. For these both distros only a few specific
340 rules are left in their own file, named after the distro. Rules which
341 are optionally installed, because they are only valid for a specific
342 architecture, or rules for subsystems which are not always used are
343 in etc/udev/packages/.
349 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
350 actions by dynamically created rules.
352 SYMLINK=="<value>" matches agains the entries in the list of
353 currently defined symlinks. The links are not created in the
354 filesystem at that point in time, but the values can be matched.
356 RUN{ignore_error}+="<program>" will ignore any exit code from the
357 program and not record as a failed event.
363 Final merge of patches/features from the Ubuntu package.
369 Control characters in filesystem label strings are no longer silenty
370 removed, but hex-encoded, to be able to uniquely identify the device
371 by its symlink in /dev/disk/by-label/.
372 If libvolume_id is used by mount(8), LABEL= will work as expected,
373 if slashes or other characters are used in the label string.
375 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
376 can be specified now. The TEST key accepts an optional mode mask
377 TEST{0100}=="<is executable file>".
379 Scsi_id now supports a mode without expecting scsi-specific sysfs
380 entries to allow the extraction of cciss-device persistent properties.
386 In the future, we may see uuid's which are just simple character
387 strings (see the DDF Raid Specification). For that reason vol_id now
388 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
389 the creation of symlinks, the *_SAFE values ensure, that no control
390 or whitespace characters are used in the filename.
392 Possible users of libvolume_id, please use the volume_id_get_* functions.
393 The public struct will go away in a future release of the library.
399 Removal of useless extras/eventrecorder.sh.
409 The directory multiplexer for dev.d/ and hotplug.d are finally removed
410 from the udev package.
416 Symlinks can have priorities now, the priority is assigned to the device
417 and specified with OPTIONS="link_priority=100". Devices with higher
418 priorities overwrite the symlinks of devices with lower priorities.
419 If the device that currently owns the link, goes away, the symlink
420 will be removed, and recreated, pointing to the next device with the
421 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
422 more reliable, if multiple devices contain the same metadata and overwrite
425 The dasd_id program is removed from the udev tree, and dasdinfo, with the
426 needed rules, are part of the s390-tools now.
428 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
429 we may get the scsi sysfs mess fixed some day, and this will only catch
430 the devices we are looking for.
432 USB serial numbers for storage devices have the target:lun now appended,
433 to make it possibble to distinguish broken multi-lun devices with all
434 the same SCSI identifiers.
436 Note: The extra "run_directory" which searches and executes stuff in
437 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
438 with the next release. Make sure, that you don't use it anymore, or
439 provides your own implementation of that inefficient stuff.
440 We are tired of reports about a "slow udev", because these directories
441 contain stuff, that runs with _every_ event, instead of using rules,
442 that run programs only for the matching events.
452 DRIVER== will match only for devices that actually have a real
453 driver. DRIVERS== must be used, if parent devices should be
454 included in the match.
456 Libvolume_id's "linux_raid" detection needed another fix.
464 Add additional check to volume_id detection of via_raid, cause
465 some company decided to put a matching pattern all over the empty
466 storage area of their music players.
470 Fix path_id for SAS devices.
474 The udev daemon can be started with --debug-trace now, which will
475 execute all events serialized to get a chance to catch a possible
476 action that crashes the box.
478 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
479 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
480 are excluded from the warning. Referencing parent attributes directly
481 may break when something in the kernel driver model changes. Udev will
482 just find the attribute by walking up the parent chain.
484 Udevtrigger now sorts the list of devices depending on the device
485 dependency, so a "usb" device is triggered after the parent "pci"
490 Revert persistent-storage ata-serial '_' '-' replacement.
496 Udevtrigger can now filter the list of devices to be triggered. Matches
497 for subsystems or sysfs attributes can be specified.
499 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
500 zero-sized files to avoid pointing to /sys and confuse broken tools which
501 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
504 The rules and scripts to create udev rules for persistent network
505 devices and optical drives are in the extras/rules_generator directory
506 now. If you use something similar, please consider replacing your own
507 version with this, to share the support effort. The rule_generator
508 installs its own rules into /etc/udev/rules.d.
510 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
511 the rule_generator depends on cdrom_id to be called in an earlier rule.
517 Renaming of some key names (the old names still work):
518 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
519 (The behavior of the key DRIVER will change soon in one of the next
520 releases, to match only the event device, please switch to DRIVERS
521 instead. If DRIVER is used, it will behave like DRIVERS, but an error
523 With the new key names, we have a more consistent and simpler scheme.
524 We can match the properties of the event device only, with: KERNEL,
525 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
526 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
527 longer mentioned in the man page and should be switched in the rule
530 ATTR{file}="value" can be used now, to write to a sysfs file of the
531 event device. Instead of:
532 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
534 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
536 All the PHYSDEV* keys are deprecated and will be removed from a
538 PHYDEVPATH - is the path of a parent device and should not be
540 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
541 matched with SUBSYSTEMS==
542 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
543 Newer kernels will have DRIVER in the environment,
544 for older kernels udev puts in. Class device will
545 no longer carry this property of a parent and
546 DRIVERS== can be used to match such a parent value.
547 Note that ENV{DRIVER} is only available for a few bus devices, where
548 the driver is already bound at device event time. On coldplug, the
549 events for a lot devices are already bound to a driver, and they will have
550 that value set. But on hotplug, at the time the kernel creates the device,
551 it can't know what driver may claim the device after that, therefore
552 in most cases it will be empty.
554 Failed events should now be re-triggered with:
555 udevtrigger --retry-failed.
556 Please switch to this command, so we keep the details of the /dev/.udev/failed/
557 files private to the udev tools. We may need to switch the current symlink
558 target, cause some obviously broken tools try to scan all files in /dev
559 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
560 million times. This takes ages on slow boxes.
562 The udevinfo attribute walk (-a) now works with giving a device node
563 name (-n) instead of a devpath (-p). The query now always works, also when
564 no database file was created by udev.
566 The built-in /etc/passwd /etc/group parser is removed, we always depend on
567 getpwnam() and getgrnam() now. One of the next releases will depend on
568 fnmatch() and may use getopt_long().
572 Bugfixes and small improvements.
576 Fix path_id for recent kernels.
582 Added support for swapping network interface names, by temporarily
583 renaming the device and wait for the target name to become free.
587 The built-in MODALIAS key and substitution is removed.
591 The binary firmware helper is replaced by the usual simple
592 shell script. Udevsend is removed from the tree.
600 Some more keys require the correct use of '==' and '=' depending
601 on the kind of operation beeing an assignment or a match. Rules
602 with invalid operations are skipped and logged to syslog. Please
603 test with udevtest if the parsing of your rules throws errors and
604 fix possibly broken rules.
608 Provide "udevsettle" to wait for all current udev events to finish.
609 It also watches the current kernel netlink queue by comparing the
610 even sequence number to make sure that there are no current pending
611 events that have not already arrived in the daemon.
615 Fix rule to skip persistent rules for removable IDE devices, which
616 also skipped optical IDE drives.
618 All *_id program are installed in /lib/udev/ by default now.
620 No binary is stripped anymore as this should be done in the
621 packaging process and not at build time.
623 libvolume_id is provided as a shared library now and vol_id is
624 linked against it. Also one of the next HAL versions will require
625 this library, and the HAL build process will also require the
626 header file to be installed. The copy of the same code in HAL will
627 be removed to have only a single copy left on the system.
631 Add persistent links for SCSI tapes. The rules file is renamed
632 to 60-persistent-storage.rules.
634 Create persistent path for usb devices. Can be used for all sorts
635 of devices that can't be distinguished by other properties like
636 multiple identical keyboards and mice connected to the same box.
638 Provide "udevtrigger" program to request events on coldplug. The
639 shell script is much too slow with thousends of devices.
643 Fix persistent disk rules to exclude removable IDE drives.
645 Warn if %e, $modalias or MODALIAS is used.
649 Fix queue export, which wasn't correct for subsequent add/remove
650 events for the same device.
654 Fix cramfs detection on big endian.
656 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
661 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
662 attributes were only checked at the parent device that matched the
663 by BUS requested subsystem. Fix it to also look at the device we
664 received the event for.
666 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
671 Fix a bug where NAME="" would prevent RUN from beeing executed.
673 RUN="/bin/program" does not longer automatically add the subsystem
674 as the first parameter. This is from the days of /sbin/hotplug
675 which is dead now and it's just confusing to need to add a space at
676 the end of the program name to prevent this.
677 If you use rules that need the subsystem as the first parameter,
678 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
679 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
683 The udev man page has moved to udev(7) as it does not describe a command
684 anymore. The programs udev, udevstart and udevsend are no longer installed
685 by default and must be copied manually, if they should be installed or
686 included in a package.
688 Fix a bug where "ignore_device" could run earlier collected RUN keys before
689 the ignore rule was applied.
691 More preparation for future sysfs changes. usb_id and scsi_id no longer
692 depend on a magic order of devices in the /devices chain. Specific devices
693 should be requested by their subsytem.
695 This will always find the scsi parent device without depending on a specific
697 dev = sysfs_device_get(devpath);
698 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
700 The "device" link in the current sysfs layout will be automatically
701 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
702 parent in the devpath. If a device is requested by it's symlink, like all
703 class devices in the new sysfs layout will look like, it gets automatically
704 resolved and substituted with the real devpath and not the symlink path.
707 A similar logic must be applied to _all_ sysfs users, including
708 scripts, that search along parent devices in sysfs. The explicit use of
709 the "device" link must be avoided. With the future sysfs layout all
710 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
711 back to the "class" or the "bus". The layout of the parent devices in
712 /devices is not necessarily expected to be stable across kernel releases and
713 searching for parents by their subsystem should make sysfs users tolerant
714 for changed parent chains.
718 Prepare udev to work with the experimental kernel patch, that moves
719 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
721 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
722 moving the class devices to /sys/devices.
724 Thanks again to Marco for help finding a hopefully nice compromise
725 to make %b simpler and working again.
729 Complete removal of libsysfs, replaced by simple helper functions
730 which are much simpler and a bit faster. The udev daemon operatesentirely
731 on event parameters and does not use sysfs for simple rules anymore.
732 Please report any new bugs/problems, that may be caused by this big
733 change. They will be fixed immediately.
735 The enumeration format character '%e' is deprecated and will be
736 removed sometimes from a future udev version. It never worked correctly
737 outside of udevstart, so we can't use it with the new parallel
738 coldplug. A simple enumeration is as useless as the devfs naming
739 scheme, just get rid of both if you still use it.
741 MODALIAS and $modalias is not needed and will be removed from one of
742 the next udev versions, replace it in all rules with ENV{MODALIAS} or
743 the sysfs "modalias" value.
745 Thanks a lot to Marco for all his help on finding and fixing bugs.
749 Let scsi_id request libata drive serial numbers from page 0x80.
751 Renamed etc/udev/persistent.rules to persistent-disk.rules and
752 added /dev/disk/by-name/* for device mapper device names.
754 Removed %e from the man page. It never worked reliably outside
755 of udevstart and udevstart is no longer recommended to use.
759 Symlinks are now exported to the event environment. Hopefully it's no
760 longer needed to run udevinfo from an event process, like it was
761 mentioned on the hotplug list:
762 UDEV [1134776873.702967] add@/block/sdb
765 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
769 Fix a problem if udevsend is used as the hotplug handler and tries to use
770 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
771 and this kind of problems will hopefully go away soon.
775 All built-in logic to work around bad sysfs timing is removed with this
776 version. The need to wait for sysfs files is almost fixed with a kernel
777 version that doesn't work with this udev version anyway. Until we fix
778 the timing of the "bus" link creation, the former integrated logic should
779 be emulated by a rule placed before all other rules:
780 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
782 The option "udev_db" does no longer exist. All udev state will be in
783 /$udev_root/.udev/ now, there is no longer an option to set this
785 If the init script or something else used this value, just depend on
786 this hardcoded path. But remember _all_content_ of this directory is
787 still private to udev and can change at any time.
789 Default location for rule sripts and helper programs is now: /lib/udev/.
790 Everything that is not useful on the commandline should go into this
791 directory. Some of the helpers in the extras folder are installed there
792 now. The rules need to be changed, to find the helpers there.
794 Also /lib/udev/devices is recommended as a directory where packages or
795 the user can place real device nodes, which get copied over to /dev at
796 every boot. This should replace the various solutions with custom config
799 Udevsend does no longer start the udev daemon. This must be done with
800 the init script that prepares /dev on tmpfs and creates the initial nodes,
801 before starting the daemon.
805 Silent a too verbose error logging for the old hotplug.d/ dev.d/
808 The copy of klibc is removed. A systemwide installed version of klibc
809 should be used to build a klibc udev now.
813 NAME="" will not create any nodes, but execute RUN keys. To completely
814 ignore an event the OPTION "ignore_device" should be used.
816 After removal of the reorder queue, events with a TIMEOUT can be executed
817 without any queuing now.
821 Fixed bug in udevd, if inotify is not available. We depend on netlink
822 uevents now, kernels without that event source will not work with that
823 version of udev anymore.
827 The rule parsing happens now in the daemon once at startup, all udev
828 event processes inherit the already parsed rules from the daemon.
829 It is shipped with SUSE10.0 and reduces heavily the system load at
830 startup. The option to save precompiled rules and let the udev process
831 pick the them up is removed, as it's no longer needed.
833 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
834 device. Libsysfs is changed to "translate" the requested link into the
835 real device path, as it would happen with the hotplug event. Otherwise
836 device removal and the udev database will not work.
838 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
841 A few improvements for vol_id, the filesytem probing code.
845 Fix a stupid typo in extras/run_directory for "make install".
847 scsi_id creates the temporary devnode now in /dev for usage with a
848 non-writable /tmp directory.
850 The uevent kernel socket buffer can carry app. 50.000 events now,
851 let's see who can break this again. :)
853 The upcoming kernel will have a new input driver core integration.
854 Some class devices are now symlinks to the real device. libsysfs
855 needs a fix for this to work correctly. Udevstart of older udev
856 versions will _not_ create these devices!
860 Fix a 'install' target in the Makefile, that prevents EXTRAS from
865 A bunch of mostly trivial bugfixes. From now on no node name or
866 symlink name can contain any character than plain whitelisted ascii
867 characters or validated utf8 byte-streams. This is needed for the
868 /dev/disk/by-label/* links, because we import untrusted data and
869 export it to the filesystem.
873 More bugfixes. If udevd was started from the kernel, we don't
874 have stdin/stdout/stderr, which broke the forked tools in some
879 Bugfix. udevstart event ordering was broken for a long time.
880 The new run_program() uncovered it, because /dev/null was not
881 available while we try to run external programs.
882 Now udevstart should create it before we run anything.
886 Minor bugfixes and some distro rules updates. If you don't have the
887 persistent disk rules in /dev/disk/by-*/* on your distro, just
888 grab it from here. :)
892 We can use socket communication now to pass events from udev to
894 RUN+="socket:/org/freedesktop/hal/udev_event"
895 will pass the whole udev event to the HAL daemon without the need
896 for a forked helper. (See ChangeLog for udevmonitor, as an example)
900 Mostly bugfixes and see ChangeLog.
902 The test for the existence of an environment value should be
904 ENV{KEY}=="*" to ENV{KEY}=="?*"
905 because "*" will not fail anymore, if the key does not exist or
910 Bugfixes and a few tweaks described in the ChangeLog.
914 Mostly a Bugfix release.
916 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
917 timing with custom rules.
921 We changed the internal rule storage format. Our large rule files took
922 2 MB of RAM, with the change we are down to 99kB.
924 If the device-node has been created with default name and no symlink or
925 options are to remenber, it is not longer stored in the udevdb. HAL will
926 need to be updated to work correctly with that change.
928 To overrride optimization flags, OPTFLAGS may be used now.
936 Major changes happened with this release. The goal is to take over the
937 complete kernel-event handling and provide a more efficient way to dispatch
938 kernel events. Replacing most of the current shell script logic and the
939 kernel forked helper with a netlink-daemon and a rule-based event handling.
941 o udevd listens to netlink events now. The first valid netlink event
942 will make udevd ignore any message from udevsend that contains a
943 SEQNUM, to avoid duplicate events. The forked events can be disabled
945 echo "" > /proc/sys/kernel/hotplug
946 For full support, the broken input-subsytem needs to be fixed, not to
947 bypass the driver core.
949 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
950 removed from udev itself and must be emulated by calling small
951 helper binaries provided in the extras folder:
952 make EXTRAS=extras/run_directory/
953 will build udev_run_devd and udev_run_hotplugd, which can be called
954 from a rule if needed:
955 RUN+="/sbin/udev_run_hotplugd"
956 The recommended way to handle this is to convert all the calls from
957 the directories to explicit udev rules and get completely rid of the
958 multiplexing. (To catch a ttyUSB event, you now no longer need to
959 fork and exit 300 tty script instances you are not interested in, it
960 is just one rule that matches exactly the device.)
962 o udev handles now _all_ events not just events for class and block
963 devices, this way it is possible to control the complete event
964 behavior with udev rules. Especially useful for rules like:
965 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
967 o As used in the modalias rule, udev supports now textual
968 substitution placeholder along with the usual format chars. This
969 needs to be documented, for now it's only visible in udev_rules_parse.c.
971 o The rule keys support now more operations. This is documented in the
972 man page. It is possible to add values to list-keys like the SYMLINK
973 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
974 Also "final"-assignments are supported by using KEY:="value", which will
975 prevent changing the key by any later rule.
977 o kernel 2.6.12 has the "detached_state" attribute removed from
978 sysfs, which was used to recognize sysfs population. We switched that
979 to wait for the "bus" link, which is only available in kernels after 2.6.11.
980 Running this udev version on older kernels may cause a short delay for
983 o To provide infrastructure for persistent device naming, the id programs:
984 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
985 to export the probed data in environment key format:
986 pim:~ # /sbin/ata_id --export /dev/hda
987 ID_MODEL=HTS726060M9AT00
988 ID_SERIAL=MRH401M4G6UM9B
992 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
993 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
996 kay@pim:~> tree /dev/disk
999 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
1000 | `-- IBM-Memory_Key -> ../../sda
1002 | |-- swap -> ../../hda1
1003 | |-- date -> ../../sda1
1004 | `-- home -> ../../hda3
1006 |-- 2E08712B0870F2E7 -> ../../hda3
1007 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
1008 |-- E845-7A89 -> ../../sda1
1009 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
1011 The IMPORT= operation will import these keys in the environment and make
1012 it available for later PROGRAM= and RUN= executed programs. The keys are
1013 also stored in the udevdb and can be queried from there with one of the
1016 o A few binaries are silently added to the repository, which can be used
1017 to replay kernel events from initramfs instead of using coldplug. udevd
1018 can be instructed now to queue-up events while the stored events from
1019 initramfs are filled into the udevd-queue. This code is still under
1020 development and there is no documentation now besides the code itself.
1021 The additional binaries get compiled, but are not installed by default.
1023 o There is also a temporary fix for a performance problem where too many
1024 events happen in parallel and every event needs to parse the rules.
1025 udev can now read precompiled rules stored on disk. This is likely to be
1026 replaced by a more elegant solution in a future udev version.
1030 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
1031 Fix for libsysfs not to expect this file was added.
1035 All rules are applied now, but only the first matching rule with a NAME-key
1036 will be applied. All later rules with NAME-key are completely ignored. This
1037 way system supplied symlinks or permissions gets applied to user-defined
1041 Please check your rules setup, if you may need to add OPTIONS="last_rule"
1042 to some rules, to keep the old behavior.
1044 The rules are read on "remove"-events too. That makes is possible to match
1045 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
1046 instruct udev to ignore an event (OPTIONS="ignore_device").
1047 The new ACTION-key may be used to let a rule act only at a "remove"-event.
1049 The new RUN-key supports rule-based execution of programs after device-node
1050 handling. This is meant as a general replacement for the dev.d/-directories
1051 to give fine grained control over the execution of programs.
1053 The %s{}-sysfs format char replacement values are searched at any of the
1054 devices in the device chain now, not only at the class-device.
1056 We support log priority levels now. The value udev_log in udev.conf is used
1057 to determine what is printed to syslog. This makes it possible to
1058 run a version with compiled-in debug messages in a production environment
1059 which is sometimes needed to find a bug.
1060 It is still possible to supress the inclusion of _any_ syslog usage with
1061 USE_LOG=false to create the smallest possible binaries if needed.
1062 The configured udev_log value can be overridden with the environment variable
1067 Possible use of a system-wide klibc:
1068 make USE_KLIBC=true KLCC=/usr/bin/klcc all
1069 will link against an external klibc and our own version will be ignored.
1073 We support an unlimited count of symlinks now.
1075 If USE_STATIC=true is passed to a glibc build, we link statically and use
1076 a built-in userdb parser to resolve user and group names.
1078 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
1079 we walk up the chain of physical devices to find a match.
1081 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
1082 easy to skip certain attribute matches without composing rules with weird
1083 character class negations like:
1084 KERNEL="[!s][!c][!d]*"
1085 this can now be replaced with:
1087 The current simple '=' is still supported, and should work as it does today,
1088 but existing rules should be converted if possible, to be better readable.
1090 We have new ENV{}== key now, to match against a maximum of 5 environment
1093 udevstart is its own binary again, because we don't need co carry this araound
1094 with every forked event.
~ianmdlvl / elogind.git / blob