5 We are currently merging the Ubuntu rules in the udev default rules,
6 and get one step closer to provide a common Linux /dev setup, regarding
7 device names, symlinks, and default device permissions. On udev startup,
8 we now expect the following groups to be resolvable to their ids with
10 disk, cdrom, floppy, tape, audio, video, lp, tty, dialout, kmem.
11 LDAP setups need to make sure, that these groups are always resolvable at
12 bootup, with only the rootfs mounted, and without network access available.
14 Some systems may need to add some new, currently not used groups, or need
15 to add some users to new groups, but the cost of this change is minimal,
16 compared to the pain the current, rather random, differences between the
17 various distributions cause for upstream projects and third-party vendors.
19 In general, "normal" users who log into a machine should never be a member
20 of any such group, but the device-access should be managed by dynamic ACLs,
21 which get added and removed for the specific users on login/logout and
22 session activity/inactivity. These groups are only provided for custom setups,
23 and mainly system services, to allow proper privilege separation.
24 A video-streaming daemon uid would be a member of "audio" and "video", to get
25 access to the sound and video devices, but no "normal" user ever belongs in
26 the "audio" group, because he could listen to the built-in microphone with
27 any ssh-session established from the other side of the world.
29 /dev/serial/by-{id,path}/ now contains links for ttyUSB devices,
30 which do not depend on the kernel device name. As usual, unique
31 devices - only a single one per product connected, or a real
32 USB serial number in the device - are always found with the same
33 name in the by-id/ directory.
34 Completely Identical devices may overwrite their names in by-id/
35 and can only be found reliably in the by-path/ directory. Devices
36 specified by by-path/ must not change their connection, like the
37 USB port number they are plugged in, to keep their name.
39 To support some advanced features, Linux 2.6.22 is the oldest supported
40 version now. The kernel config with enabled SYSFS_DEPRECATED is no longer
41 supported. Older kernels should still work, and devices nodes should be
42 reliably created, but some rules and libudev will not work correctly because
43 the old kernels do not provide the expected information or interfaces.
49 Fix for a possible segfault while swapping network interface names in udev
56 The group "video" is part of the default rules now.
60 Bugfix for kernels using SYSFS_DEPRECATED* option and finding parent
61 block devices in some cases. No common distro uses this option anymore,
62 and we do not get enough testing for this and recent udev versions. If
63 this option is not needed to run some old distro with a new kernel,
64 it should be disabled in the kernel config.
66 Bugfix for the $links substitution variable, which may crash if no links
67 are created. This should not happen in usual setups because we always
68 create /dev/{block,char}/ links.
70 The strings of the parsed rules, which are kept in memory, no longer
71 contain duplicate entries, or duplicate tails of strings. This, and the
72 new rules parsing/matching code reduces the total in-memory size of
73 a huge distro rule sets to 0.08 MB, compared to the 1.2MB of udev
76 The export of DEVTYPE=disk/partition got removed from the default
77 rules. This value is available from the kernel. The pnp shell script
78 modprobe hack is removed from the default rules. ACPI devices have _proper_
79 modalias support and take care of the same functionality.
80 Installations which support old kernels, but install current default
81 udev rules may want to add that to the compat rules file.
83 Libvolume_id now always probes for all known filesystems, and does not
84 stop at the first match. Some filesystems are marked as "exclusive probe",
85 and if any other filesytem type matches at the same time, libvolume_id
86 will, by default, not return any probing result. This is intended to prevent
87 mis-detection with conflicting left-over signatures found from earlier
88 file system formats. That way, we no longer depend on the probe-order
89 in case of multiple competing signatures. In some setups the kernel allows
90 to mount a volume with just the old filesystem signature still in place.
91 This may damage the new filesystem and cause data-loss, just by mounting
92 it. Because volume_id can not decide which one the correct signature is,
93 the wrong signatures need to be removed manually from the volume, or the
94 volume needs to be reformatted, to enable filesystem detection and possible
99 Fix segfault if compiled without optimization and dbg() does not get
100 compiled out and uses variables which are not available.
104 Bugfixes. (And maybe new bugs. :))
106 The rule matching engine got converted from a rule list to a token
107 array which reduced the in-memory rules representation of a full
108 featured distros with thousends of udev rules from 1.2MB to 0.12 MB.
109 Limits like 5 ENV and ATTR matches, and one single instance for most
110 other keys per rule are gone.
112 The NAME assignment is no longer special cased. If later rules assign
113 a NAME value again, the former value will be overwritten. As usual
114 for most other keys, the NAME value can be protected by doing a final
115 assignment with NAME:="<value>".
117 All udev code now uses libudev, which is also exported. The library
118 is still under development, marked as experimental, and its interface
119 may change as long as the DeviceKit integration is not finished.
121 Many thanks to Alan Jenkins for his continuous help, and finding and
122 optimizing some of the computing expensive parts.
128 Kernel devices and device nodes are connected now by reverse indizes in
129 /sys and /dev. A device number retrieved by a stat() or similar, the
130 kernel device directory can be found by looking up:
131 /sys/dev/{block,char}/<maj>:<min>
132 and the device node of the same device by looking up:
133 /dev/{block,char}/<maj>:<min>
137 Fix recently introduced bug, which caused a compilation without large
138 file support, where vol_id does not recognize raid signatures at the end
141 Firewire disks now create both, by-id/scsi-* and by-id/ieee-* links.
142 Seems some kernel versions prevent the creation of the ieee-* links,
143 so people used the scsi-* link which disappeared now.
145 More libudev work. Almost all udevadm functionality comes from libudev
148 udevadm trigger has a new option --type, which allows to trigger events
149 for "devices", for "subsystems", or "failed" devices. The old option
150 --retry-failed" still works, but is no longer mentioned in the man page.
156 The udevadm info --device-id-of-file= output has changed to use
157 the obvious format. Possible current users should use the --export
158 option which is not affected.
160 The old udev commands symlinks to udevadm are not installed, if
161 these symlinks are used, a warning is printed.
167 Optical drive's media is no longer probed for raid signatures,
168 reading the end of the device causes some devices to malfunction.
169 Also the offset of the last session found is used now to probe
172 The volume_id library got a major version number update to 1,
173 some deprecated functions are removed.
175 A shared library "libudev" gets installed now to provide access
176 to udev device information. DeviceKit, the successor of HAL, will
177 need this library to access the udev database and search sysfs for
179 The library is currently in an experimental state, also the API is
180 expected to change, as long as the DeviceKit integration is not
185 We use ./configure now. See INSTALL for details. Current
188 "/usr" - prefix for man pages, include files
190 "" - the root filesystem, prefix for libs and binaries
194 "lib" - directory name for libraries, not a path name
195 multilib 64bit systems may use "lib64" instead of "lib"
197 compile-in verbose debug messages
199 disable all logging and compile-out all log strings
201 link against SELInux libraries, to set the expected context
204 In the default rules, the group "disk" gets permissions 0660 instead
205 of 0640. One small step closer to unify distro rules. Some day, all
206 distros hopefully end up with the same set of rules.
208 No symlinks to udevadm are installed anymore, if they are still needed,
209 they should be provided by the package.
215 Default udev rules, which are not supposed to be edited by the user, should
216 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
217 the udev package and will be replaced with an update. Udev will pick up rule
219 /lib/udev/rules.d/ - default installed rules
220 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
221 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
222 It does not matter in which directory a rule file lives, all files are sorted
225 To help creating /dev/root, we have now:
226 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
229 In case the current --device-id-of-file is already used, please switch to
230 the --export format version, it saves the output parsing and the old
231 format will be changed to use ':' as a separator, like the format in the
236 Fix cdrom_id to properly recognize blank media.
242 Tape drive id-data is queried from /dev/bsg/* instead of the tape
243 nodes. This avoids rewinding tapes on open().
249 The symlinks udevcontrol and udevtrigger are no longer installed by
252 The scsi_id program does not depend on sysfs anymore. It can speak
253 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
254 data, which should solve some old problems with tape devices, where
255 we better do not open all tape device nodes to identify the device.
261 The cdrom_id program is replaced by an advanced version, which can
262 detect most common device types, and also properties of the inserted
263 media. This is part of moving some basic functionality from HAL into
264 udev (and the kernel).
270 The last WAIT_FOR_SYSFS rule is removed from the default rules.
272 The symlinks to udevadm for the debugging tools: udevmonitor and
273 udevtest are no longer created.
275 The symlinks to the udevadm man page for the old tool names are
278 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
279 should be prefixed with '@' to indicate that the path is not a
290 Udevstart is removed from the tree, it did not get installed for
291 a long time now, and is long replaced by trigger and settle.
297 All udev tools are merged into a single binary called udevadm.
298 The old names of the tools are built-in commands in udevadm now.
299 Symlinks to udevadm, with the names of the old tools, provide
300 the same functionality as the standalone tools. There is also
301 only a single udevadm.8 man page left for all tools.
303 Tools like mkinitramfs should be checked, if they need to include
304 udevadm in the list of files.
314 The etc/udev/rules.d/ directory now contains a default set of basic
315 udev rules. This initial version is the result of a rules file merge
316 of Fedora and openSUSE. For these both distros only a few specific
317 rules are left in their own file, named after the distro. Rules which
318 are optionally installed, because they are only valid for a specific
319 architecture, or rules for subsystems which are not always used are
320 in etc/udev/packages/.
326 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
327 actions by dynamically created rules.
329 SYMLINK=="<value>" matches agains the entries in the list of
330 currently defined symlinks. The links are not created in the
331 filesystem at that point in time, but the values can be matched.
333 RUN{ignore_error}+="<program>" will ignore any exit code from the
334 program and not record as a failed event.
340 Final merge of patches/features from the Ubuntu package.
346 Control characters in filesystem label strings are no longer silenty
347 removed, but hex-encoded, to be able to uniquely identify the device
348 by its symlink in /dev/disk/by-label/.
349 If libvolume_id is used by mount(8), LABEL= will work as expected,
350 if slashes or other characters are used in the label string.
352 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
353 can be specified now. The TEST key accepts an optional mode mask
354 TEST{0100}=="<is executable file>".
356 Scsi_id now supports a mode without expecting scsi-specific sysfs
357 entries to allow the extraction of cciss-device persistent properties.
363 In the future, we may see uuid's which are just simple character
364 strings (see the DDF Raid Specification). For that reason vol_id now
365 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
366 the creation of symlinks, the *_SAFE values ensure, that no control
367 or whitespace characters are used in the filename.
369 Possible users of libvolume_id, please use the volume_id_get_* functions.
370 The public struct will go away in a future release of the library.
376 Removal of useless extras/eventrecorder.sh.
386 The directory multiplexer for dev.d/ and hotplug.d are finally removed
387 from the udev package.
393 Symlinks can have priorities now, the priority is assigned to the device
394 and specified with OPTIONS="link_priority=100". Devices with higher
395 priorities overwrite the symlinks of devices with lower priorities.
396 If the device that currently owns the link, goes away, the symlink
397 will be removed, and recreated, pointing to the next device with the
398 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
399 more reliable, if multiple devices contain the same metadata and overwrite
402 The dasd_id program is removed from the udev tree, and dasdinfo, with the
403 needed rules, are part of the s390-tools now.
405 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
406 we may get the scsi sysfs mess fixed some day, and this will only catch
407 the devices we are looking for.
409 USB serial numbers for storage devices have the target:lun now appended,
410 to make it possibble to distinguish broken multi-lun devices with all
411 the same SCSI identifiers.
413 Note: The extra "run_directory" which searches and executes stuff in
414 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
415 with the next release. Make sure, that you don't use it anymore, or
416 provides your own implementation of that inefficient stuff.
417 We are tired of reports about a "slow udev", because these directories
418 contain stuff, that runs with _every_ event, instead of using rules,
419 that run programs only for the matching events.
429 DRIVER== will match only for devices that actually have a real
430 driver. DRIVERS== must be used, if parent devices should be
431 included in the match.
433 Libvolume_id's "linux_raid" detection needed another fix.
441 Add additional check to volume_id detection of via_raid, cause
442 some company decided to put a matching pattern all over the empty
443 storage area of their music players.
447 Fix path_id for SAS devices.
451 The udev daemon can be started with --debug-trace now, which will
452 execute all events serialized to get a chance to catch a possible
453 action that crashes the box.
455 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
456 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
457 are excluded from the warning. Referencing parent attributes directly
458 may break when something in the kernel driver model changes. Udev will
459 just find the attribute by walking up the parent chain.
461 Udevtrigger now sorts the list of devices depending on the device
462 dependency, so a "usb" device is triggered after the parent "pci"
467 Revert persistent-storage ata-serial '_' '-' replacement.
473 Udevtrigger can now filter the list of devices to be triggered. Matches
474 for subsystems or sysfs attributes can be specified.
476 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
477 zero-sized files to avoid pointing to /sys and confuse broken tools which
478 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
481 The rules and scripts to create udev rules for persistent network
482 devices and optical drives are in the extras/rules_generator directory
483 now. If you use something similar, please consider replacing your own
484 version with this, to share the support effort. The rule_generator
485 installs its own rules into /etc/udev/rules.d.
487 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
488 the rule_generator depends on cdrom_id to be called in an earlier rule.
494 Renaming of some key names (the old names still work):
495 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
496 (The behavior of the key DRIVER will change soon in one of the next
497 releases, to match only the event device, please switch to DRIVERS
498 instead. If DRIVER is used, it will behave like DRIVERS, but an error
500 With the new key names, we have a more consistent and simpler scheme.
501 We can match the properties of the event device only, with: KERNEL,
502 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
503 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
504 longer mentioned in the man page and should be switched in the rule
507 ATTR{file}="value" can be used now, to write to a sysfs file of the
508 event device. Instead of:
509 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
511 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
513 All the PHYSDEV* keys are deprecated and will be removed from a
515 PHYDEVPATH - is the path of a parent device and should not be
517 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
518 matched with SUBSYSTEMS==
519 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
520 Newer kernels will have DRIVER in the environment,
521 for older kernels udev puts in. Class device will
522 no longer carry this property of a parent and
523 DRIVERS== can be used to match such a parent value.
524 Note that ENV{DRIVER} is only available for a few bus devices, where
525 the driver is already bound at device event time. On coldplug, the
526 events for a lot devices are already bound to a driver, and they will have
527 that value set. But on hotplug, at the time the kernel creates the device,
528 it can't know what driver may claim the device after that, therefore
529 in most cases it will be empty.
531 Failed events should now be re-triggered with:
532 udevtrigger --retry-failed.
533 Please switch to this command, so we keep the details of the /dev/.udev/failed/
534 files private to the udev tools. We may need to switch the current symlink
535 target, cause some obviously broken tools try to scan all files in /dev
536 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
537 million times. This takes ages on slow boxes.
539 The udevinfo attribute walk (-a) now works with giving a device node
540 name (-n) instead of a devpath (-p). The query now always works, also when
541 no database file was created by udev.
543 The built-in /etc/passwd /etc/group parser is removed, we always depend on
544 getpwnam() and getgrnam() now. One of the next releases will depend on
545 fnmatch() and may use getopt_long().
549 Bugfixes and small improvements.
553 Fix path_id for recent kernels.
559 Added support for swapping network interface names, by temporarily
560 renaming the device and wait for the target name to become free.
564 The built-in MODALIAS key and substitution is removed.
568 The binary firmware helper is replaced by the usual simple
569 shell script. Udevsend is removed from the tree.
577 Some more keys require the correct use of '==' and '=' depending
578 on the kind of operation beeing an assignment or a match. Rules
579 with invalid operations are skipped and logged to syslog. Please
580 test with udevtest if the parsing of your rules throws errors and
581 fix possibly broken rules.
585 Provide "udevsettle" to wait for all current udev events to finish.
586 It also watches the current kernel netlink queue by comparing the
587 even sequence number to make sure that there are no current pending
588 events that have not already arrived in the daemon.
592 Fix rule to skip persistent rules for removable IDE devices, which
593 also skipped optical IDE drives.
595 All *_id program are installed in /lib/udev/ by default now.
597 No binary is stripped anymore as this should be done in the
598 packaging process and not at build time.
600 libvolume_id is provided as a shared library now and vol_id is
601 linked against it. Also one of the next HAL versions will require
602 this library, and the HAL build process will also require the
603 header file to be installed. The copy of the same code in HAL will
604 be removed to have only a single copy left on the system.
608 Add persistent links for SCSI tapes. The rules file is renamed
609 to 60-persistent-storage.rules.
611 Create persistent path for usb devices. Can be used for all sorts
612 of devices that can't be distinguished by other properties like
613 multiple identical keyboards and mice connected to the same box.
615 Provide "udevtrigger" program to request events on coldplug. The
616 shell script is much too slow with thousends of devices.
620 Fix persistent disk rules to exclude removable IDE drives.
622 Warn if %e, $modalias or MODALIAS is used.
626 Fix queue export, which wasn't correct for subsequent add/remove
627 events for the same device.
631 Fix cramfs detection on big endian.
633 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
638 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
639 attributes were only checked at the parent device that matched the
640 by BUS requested subsystem. Fix it to also look at the device we
641 received the event for.
643 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
648 Fix a bug where NAME="" would prevent RUN from beeing executed.
650 RUN="/bin/program" does not longer automatically add the subsystem
651 as the first parameter. This is from the days of /sbin/hotplug
652 which is dead now and it's just confusing to need to add a space at
653 the end of the program name to prevent this.
654 If you use rules that need the subsystem as the first parameter,
655 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
656 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
660 The udev man page has moved to udev(7) as it does not describe a command
661 anymore. The programs udev, udevstart and udevsend are no longer installed
662 by default and must be copied manually, if they should be installed or
663 included in a package.
665 Fix a bug where "ignore_device" could run earlier collected RUN keys before
666 the ignore rule was applied.
668 More preparation for future sysfs changes. usb_id and scsi_id no longer
669 depend on a magic order of devices in the /devices chain. Specific devices
670 should be requested by their subsytem.
672 This will always find the scsi parent device without depending on a specific
674 dev = sysfs_device_get(devpath);
675 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
677 The "device" link in the current sysfs layout will be automatically
678 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
679 parent in the devpath. If a device is requested by it's symlink, like all
680 class devices in the new sysfs layout will look like, it gets automatically
681 resolved and substituted with the real devpath and not the symlink path.
684 A similar logic must be applied to _all_ sysfs users, including
685 scripts, that search along parent devices in sysfs. The explicit use of
686 the "device" link must be avoided. With the future sysfs layout all
687 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
688 back to the "class" or the "bus". The layout of the parent devices in
689 /devices is not necessarily expected to be stable across kernel releases and
690 searching for parents by their subsystem should make sysfs users tolerant
691 for changed parent chains.
695 Prepare udev to work with the experimental kernel patch, that moves
696 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
698 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
699 moving the class devices to /sys/devices.
701 Thanks again to Marco for help finding a hopefully nice compromise
702 to make %b simpler and working again.
706 Complete removal of libsysfs, replaced by simple helper functions
707 which are much simpler and a bit faster. The udev daemon operatesentirely
708 on event parameters and does not use sysfs for simple rules anymore.
709 Please report any new bugs/problems, that may be caused by this big
710 change. They will be fixed immediately.
712 The enumeration format character '%e' is deprecated and will be
713 removed sometimes from a future udev version. It never worked correctly
714 outside of udevstart, so we can't use it with the new parallel
715 coldplug. A simple enumeration is as useless as the devfs naming
716 scheme, just get rid of both if you still use it.
718 MODALIAS and $modalias is not needed and will be removed from one of
719 the next udev versions, replace it in all rules with ENV{MODALIAS} or
720 the sysfs "modalias" value.
722 Thanks a lot to Marco for all his help on finding and fixing bugs.
726 Let scsi_id request libata drive serial numbers from page 0x80.
728 Renamed etc/udev/persistent.rules to persistent-disk.rules and
729 added /dev/disk/by-name/* for device mapper device names.
731 Removed %e from the man page. It never worked reliably outside
732 of udevstart and udevstart is no longer recommended to use.
736 Symlinks are now exported to the event environment. Hopefully it's no
737 longer needed to run udevinfo from an event process, like it was
738 mentioned on the hotplug list:
739 UDEV [1134776873.702967] add@/block/sdb
742 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
746 Fix a problem if udevsend is used as the hotplug handler and tries to use
747 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
748 and this kind of problems will hopefully go away soon.
752 All built-in logic to work around bad sysfs timing is removed with this
753 version. The need to wait for sysfs files is almost fixed with a kernel
754 version that doesn't work with this udev version anyway. Until we fix
755 the timing of the "bus" link creation, the former integrated logic should
756 be emulated by a rule placed before all other rules:
757 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
759 The option "udev_db" does no longer exist. All udev state will be in
760 /$udev_root/.udev/ now, there is no longer an option to set this
762 If the init script or something else used this value, just depend on
763 this hardcoded path. But remember _all_content_ of this directory is
764 still private to udev and can change at any time.
766 Default location for rule sripts and helper programs is now: /lib/udev/.
767 Everything that is not useful on the commandline should go into this
768 directory. Some of the helpers in the extras folder are installed there
769 now. The rules need to be changed, to find the helpers there.
771 Also /lib/udev/devices is recommended as a directory where packages or
772 the user can place real device nodes, which get copied over to /dev at
773 every boot. This should replace the various solutions with custom config
776 Udevsend does no longer start the udev daemon. This must be done with
777 the init script that prepares /dev on tmpfs and creates the initial nodes,
778 before starting the daemon.
782 Silent a too verbose error logging for the old hotplug.d/ dev.d/
785 The copy of klibc is removed. A systemwide installed version of klibc
786 should be used to build a klibc udev now.
790 NAME="" will not create any nodes, but execute RUN keys. To completely
791 ignore an event the OPTION "ignore_device" should be used.
793 After removal of the reorder queue, events with a TIMEOUT can be executed
794 without any queuing now.
798 Fixed bug in udevd, if inotify is not available. We depend on netlink
799 uevents now, kernels without that event source will not work with that
800 version of udev anymore.
804 The rule parsing happens now in the daemon once at startup, all udev
805 event processes inherit the already parsed rules from the daemon.
806 It is shipped with SUSE10.0 and reduces heavily the system load at
807 startup. The option to save precompiled rules and let the udev process
808 pick the them up is removed, as it's no longer needed.
810 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
811 device. Libsysfs is changed to "translate" the requested link into the
812 real device path, as it would happen with the hotplug event. Otherwise
813 device removal and the udev database will not work.
815 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
818 A few improvements for vol_id, the filesytem probing code.
822 Fix a stupid typo in extras/run_directory for "make install".
824 scsi_id creates the temporary devnode now in /dev for usage with a
825 non-writable /tmp directory.
827 The uevent kernel socket buffer can carry app. 50.000 events now,
828 let's see who can break this again. :)
830 The upcoming kernel will have a new input driver core integration.
831 Some class devices are now symlinks to the real device. libsysfs
832 needs a fix for this to work correctly. Udevstart of older udev
833 versions will _not_ create these devices!
837 Fix a 'install' target in the Makefile, that prevents EXTRAS from
842 A bunch of mostly trivial bugfixes. From now on no node name or
843 symlink name can contain any character than plain whitelisted ascii
844 characters or validated utf8 byte-streams. This is needed for the
845 /dev/disk/by-label/* links, because we import untrusted data and
846 export it to the filesystem.
850 More bugfixes. If udevd was started from the kernel, we don't
851 have stdin/stdout/stderr, which broke the forked tools in some
856 Bugfix. udevstart event ordering was broken for a long time.
857 The new run_program() uncovered it, because /dev/null was not
858 available while we try to run external programs.
859 Now udevstart should create it before we run anything.
863 Minor bugfixes and some distro rules updates. If you don't have the
864 persistent disk rules in /dev/disk/by-*/* on your distro, just
865 grab it from here. :)
869 We can use socket communication now to pass events from udev to
871 RUN+="socket:/org/freedesktop/hal/udev_event"
872 will pass the whole udev event to the HAL daemon without the need
873 for a forked helper. (See ChangeLog for udevmonitor, as an example)
877 Mostly bugfixes and see ChangeLog.
879 The test for the existence of an environment value should be
881 ENV{KEY}=="*" to ENV{KEY}=="?*"
882 because "*" will not fail anymore, if the key does not exist or
887 Bugfixes and a few tweaks described in the ChangeLog.
891 Mostly a Bugfix release.
893 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
894 timing with custom rules.
898 We changed the internal rule storage format. Our large rule files took
899 2 MB of RAM, with the change we are down to 99kB.
901 If the device-node has been created with default name and no symlink or
902 options are to remenber, it is not longer stored in the udevdb. HAL will
903 need to be updated to work correctly with that change.
905 To overrride optimization flags, OPTFLAGS may be used now.
913 Major changes happened with this release. The goal is to take over the
914 complete kernel-event handling and provide a more efficient way to dispatch
915 kernel events. Replacing most of the current shell script logic and the
916 kernel forked helper with a netlink-daemon and a rule-based event handling.
918 o udevd listens to netlink events now. The first valid netlink event
919 will make udevd ignore any message from udevsend that contains a
920 SEQNUM, to avoid duplicate events. The forked events can be disabled
922 echo "" > /proc/sys/kernel/hotplug
923 For full support, the broken input-subsytem needs to be fixed, not to
924 bypass the driver core.
926 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
927 removed from udev itself and must be emulated by calling small
928 helper binaries provided in the extras folder:
929 make EXTRAS=extras/run_directory/
930 will build udev_run_devd and udev_run_hotplugd, which can be called
931 from a rule if needed:
932 RUN+="/sbin/udev_run_hotplugd"
933 The recommended way to handle this is to convert all the calls from
934 the directories to explicit udev rules and get completely rid of the
935 multiplexing. (To catch a ttyUSB event, you now no longer need to
936 fork and exit 300 tty script instances you are not interested in, it
937 is just one rule that matches exactly the device.)
939 o udev handles now _all_ events not just events for class and block
940 devices, this way it is possible to control the complete event
941 behavior with udev rules. Especially useful for rules like:
942 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
944 o As used in the modalias rule, udev supports now textual
945 substitution placeholder along with the usual format chars. This
946 needs to be documented, for now it's only visible in udev_rules_parse.c.
948 o The rule keys support now more operations. This is documented in the
949 man page. It is possible to add values to list-keys like the SYMLINK
950 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
951 Also "final"-assignments are supported by using KEY:="value", which will
952 prevent changing the key by any later rule.
954 o kernel 2.6.12 has the "detached_state" attribute removed from
955 sysfs, which was used to recognize sysfs population. We switched that
956 to wait for the "bus" link, which is only available in kernels after 2.6.11.
957 Running this udev version on older kernels may cause a short delay for
960 o To provide infrastructure for persistent device naming, the id programs:
961 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
962 to export the probed data in environment key format:
963 pim:~ # /sbin/ata_id --export /dev/hda
964 ID_MODEL=HTS726060M9AT00
965 ID_SERIAL=MRH401M4G6UM9B
969 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
970 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
973 kay@pim:~> tree /dev/disk
976 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
977 | `-- IBM-Memory_Key -> ../../sda
979 | |-- swap -> ../../hda1
980 | |-- date -> ../../sda1
981 | `-- home -> ../../hda3
983 |-- 2E08712B0870F2E7 -> ../../hda3
984 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
985 |-- E845-7A89 -> ../../sda1
986 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
988 The IMPORT= operation will import these keys in the environment and make
989 it available for later PROGRAM= and RUN= executed programs. The keys are
990 also stored in the udevdb and can be queried from there with one of the
993 o A few binaries are silently added to the repository, which can be used
994 to replay kernel events from initramfs instead of using coldplug. udevd
995 can be instructed now to queue-up events while the stored events from
996 initramfs are filled into the udevd-queue. This code is still under
997 development and there is no documentation now besides the code itself.
998 The additional binaries get compiled, but are not installed by default.
1000 o There is also a temporary fix for a performance problem where too many
1001 events happen in parallel and every event needs to parse the rules.
1002 udev can now read precompiled rules stored on disk. This is likely to be
1003 replaced by a more elegant solution in a future udev version.
1007 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
1008 Fix for libsysfs not to expect this file was added.
1012 All rules are applied now, but only the first matching rule with a NAME-key
1013 will be applied. All later rules with NAME-key are completely ignored. This
1014 way system supplied symlinks or permissions gets applied to user-defined
1018 Please check your rules setup, if you may need to add OPTIONS="last_rule"
1019 to some rules, to keep the old behavior.
1021 The rules are read on "remove"-events too. That makes is possible to match
1022 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
1023 instruct udev to ignore an event (OPTIONS="ignore_device").
1024 The new ACTION-key may be used to let a rule act only at a "remove"-event.
1026 The new RUN-key supports rule-based execution of programs after device-node
1027 handling. This is meant as a general replacement for the dev.d/-directories
1028 to give fine grained control over the execution of programs.
1030 The %s{}-sysfs format char replacement values are searched at any of the
1031 devices in the device chain now, not only at the class-device.
1033 We support log priority levels now. The value udev_log in udev.conf is used
1034 to determine what is printed to syslog. This makes it possible to
1035 run a version with compiled-in debug messages in a production environment
1036 which is sometimes needed to find a bug.
1037 It is still possible to supress the inclusion of _any_ syslog usage with
1038 USE_LOG=false to create the smallest possible binaries if needed.
1039 The configured udev_log value can be overridden with the environment variable
1044 Possible use of a system-wide klibc:
1045 make USE_KLIBC=true KLCC=/usr/bin/klcc all
1046 will link against an external klibc and our own version will be ignored.
1050 We support an unlimited count of symlinks now.
1052 If USE_STATIC=true is passed to a glibc build, we link statically and use
1053 a built-in userdb parser to resolve user and group names.
1055 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
1056 we walk up the chain of physical devices to find a match.
1058 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
1059 easy to skip certain attribute matches without composing rules with weird
1060 character class negations like:
1061 KERNEL="[!s][!c][!d]*"
1062 this can now be replaced with:
1064 The current simple '=' is still supported, and should work as it does today,
1065 but existing rules should be converted if possible, to be better readable.
1067 We have new ENV{}== key now, to match against a maximum of 5 environment
1070 udevstart is its own binary again, because we don't need co carry this araound
1071 with every forked event.
~ianmdlvl / elogind.git / blob