5 The udevadm trigger "--retry-failed" option, which is replaced since quite
6 a while by "--type=failed" is removed.
8 The failed tracking was not working at all for a few releases. The RUN
9 option "ignore_error" is replaced by a "fail_event_on_error" option, and the
10 default is not to track any failing RUN executions.
12 New keymaps, new modem, hid2hci updated.
16 Fix possible crash in udevd when worker processes are busy, rules are
17 changed at the same time, and workers get killed to reload the rules.
23 Properties set with ENV{.FOO}="bar" are marked private by starting the
24 name with a '.'. They will not be stored in the database, and not be
25 exported with the event.
27 Firmware files are looked up in:
28 /lib/firmware/updates/$(uname -r)
30 /lib/firmware/$(uname -r)
34 ATA devices switched the property from ID_BUS=scsi to ID_BUS=ata.
35 ata_id, instead of scsi_id, is the default tool now for ATA devices.
41 The configure options have changed because another library needs to be
42 installed in a different location. Instead of exec_prefix and udev_prefix,
43 libdir, rootlibdir and libexecdir are used. The Details are explained in
46 Event processes now get re-used after they handled an event. This reduces
47 the number of forks and the pressure on the CPU significantly, because
48 cloned event processes no longer cause page faults in the main daemon.
49 After the events have settled, a few worker processes stay around for
50 future events, all others get cleaned up.
52 To be able to use signalfd(), udev depends on kernel version 2.6.25 now.
53 Also inotify support is mandatory now to run udev.
55 The format of the queue exported by the udev damon has changed. There is
56 no longer a /dev/.udev/queue/ directory. The current event queue can be
57 accessed with udevadm settle and libudedv.
59 Libudev does not have the unstable API header anymore. From now on,
60 incompatible changes will be handled by bumping the library major version.
62 To build udev from the git tree gtk-doc is needed now. The tarballs will
63 build without it and contain the pre-built documentation. An online copy
65 http://www.kernel.org/pub/linux/utils/kernel/hotplug/libudev/
67 The tools from the udev-extras repository have been merged into the main
68 udev repository. Some of the extras have larger external dependencies, and
69 they can be disabled with the configure switch --disable-extras.
75 The program vol_id and the library libvolume_id are removed from the
76 repository. Libvolume_id is merged with libblkid from the util-linux-ng
77 package. Persistent disk links for label and uuid depend on the
78 util-linux-ng version (2.15) of blkid now. Older versions of blkid
79 can not be used with udev.
81 Libudev allows to subscribe to udev events. To prevent unwanted messages
82 to be delivered, and waking up the subscribing process, a filter can be
83 installed, to drop messages inside a kernel socket filter. The filters
84 match on the <subsytem>:<devtype> properties of the device.
85 This is part of the ongoing effort to replace HAL, and switch current
86 users over to directly use libudev.
87 Libudev is still marked as experimental, and its interface might
88 eventually change if needed, but no major changes of the currently exported
89 interface are expected anymore, and a first stable release should happen
92 A too old kernel (2.6.21) or a kernel with CONFIG_SYSFS_DEPRECATED
93 is not supported since while and udevd will log an error message at
94 startup. It should still be able to boot-up, but advanced rules and system
95 services which depend on the information not available in the old sysfs
96 format will fail to work correctly.
98 DVB device naming is supplied by the kernel now. In case older kernels
99 need to be supported, the old shell script should be added to a compat
106 The processed udev events get send back to the netlink socket. Libudev
107 provides access to these events. This is work-in-progress, to replace
108 the DeviceKit daemon functionality directly with libudev. There are
109 upcoming kernel changes to allow non-root users to subcribe to these
116 "udevadm settle" now optionally accepts a range of events to wait for,
117 instead of waiting for "all" events.
123 The installed watch for block device metadata changes is now removed
124 during event hadling, because some (broken) tools may be called from udev
125 rules and (wrongly) open the device with write access. After the finished
126 event handling the watch is restored.
132 Device nodes can be watched for changes with inotify with OPTIONS="watch".
133 If closed after being opened for writing, a "change" uevent will occur.
134 /dev/disk/by-{label,uuid}/* symlinks will be automatically updated.
140 The udevadm test command has no longer a --force option, nodes and symlinks
141 are always updated with a test run now.
143 The udevd daemon can be started with --resolve-names=never to avoid all user
144 and group lookups (e.g. in cut-down systems) or --resolve-names=late to
145 lookup user and groups every time events are handled.
151 We are currently merging the Ubuntu rules in the udev default rules,
152 and get one step closer to provide a common Linux /dev setup, regarding
153 device names, symlinks, and default device permissions. On udev startup,
154 we now expect the following groups to be resolvable to their ids with
156 disk, cdrom, floppy, tape, audio, video, lp, tty, dialout, kmem.
157 LDAP setups need to make sure, that these groups are always resolvable at
158 bootup, with only the rootfs mounted, and without network access available.
160 Some systems may need to add some new, currently not used groups, or need
161 to add some users to new groups, but the cost of this change is minimal,
162 compared to the pain the current, rather random, differences between the
163 various distributions cause for upstream projects and third-party vendors.
165 In general, "normal" users who log into a machine should never be a member
166 of any such group, but the device-access should be managed by dynamic ACLs,
167 which get added and removed for the specific users on login/logout and
168 session activity/inactivity. These groups are only provided for custom setups,
169 and mainly system services, to allow proper privilege separation.
170 A video-streaming daemon uid would be a member of "audio" and "video", to get
171 access to the sound and video devices, but no "normal" user should ever belong
172 to the "audio" group, because he could listen to the built-in microphone with
173 any ssh-session established from the other side of the world.
175 /dev/serial/by-{id,path}/ now contains links for ttyUSB devices,
176 which do not depend on the kernel device name. As usual, unique
177 devices - only a single one per product connected, or a real
178 USB serial number in the device - are always found with the same
179 name in the by-id/ directory.
180 Completely identical devices may overwrite their names in by-id/
181 and can only be found reliably in the by-path/ directory. Devices
182 specified by by-path/ must not change their connection, like the
183 USB port number they are plugged in, to keep their name.
185 To support some advanced features, Linux 2.6.22 is the oldest supported
186 version now. The kernel config with enabled SYSFS_DEPRECATED is no longer
187 supported. Older kernels should still work, and devices nodes should be
188 reliably created, but some rules and libudev will not work correctly because
189 the old kernels do not provide the expected information or interfaces.
195 Fix for a possible segfault while swapping network interface names in udev
202 The group "video" is part of the default rules now.
206 Bugfix for kernels using SYSFS_DEPRECATED* option and finding parent
207 block devices in some cases. No common distro uses this option anymore,
208 and we do not get enough testing for this and recent udev versions. If
209 this option is not needed to run some old distro with a new kernel,
210 it should be disabled in the kernel config.
212 Bugfix for the $links substitution variable, which may crash if no links
213 are created. This should not happen in usual setups because we always
214 create /dev/{block,char}/ links.
216 The strings of the parsed rules, which are kept in memory, no longer
217 contain duplicate entries, or duplicate tails of strings. This, and the
218 new rules parsing/matching code reduces the total in-memory size of
219 a huge distro rule sets to 0.08 MB, compared to the 1.2MB of udev
222 The export of DEVTYPE=disk/partition got removed from the default
223 rules. This value is available from the kernel. The pnp shell script
224 modprobe hack is removed from the default rules. ACPI devices have _proper_
225 modalias support and take care of the same functionality.
226 Installations which support old kernels, but install current default
227 udev rules may want to add that to the compat rules file.
229 Libvolume_id now always probes for all known filesystems, and does not
230 stop at the first match. Some filesystems are marked as "exclusive probe",
231 and if any other filesytem type matches at the same time, libvolume_id
232 will, by default, not return any probing result. This is intended to prevent
233 mis-detection with conflicting left-over signatures found from earlier
234 file system formats. That way, we no longer depend on the probe-order
235 in case of multiple competing signatures. In some setups the kernel allows
236 to mount a volume with just the old filesystem signature still in place.
237 This may damage the new filesystem and cause data-loss, just by mounting
238 it. Because volume_id can not decide which one the correct signature is,
239 the wrong signatures need to be removed manually from the volume, or the
240 volume needs to be reformatted, to enable filesystem detection and possible
245 Fix segfault if compiled without optimization and dbg() does not get
246 compiled out and uses variables which are not available.
250 Bugfixes. (And maybe new bugs. :))
252 The rule matching engine got converted from a rule list to a token
253 array which reduced the in-memory rules representation of a full
254 featured distros with thousends of udev rules from 1.2MB to 0.12 MB.
255 Limits like 5 ENV and ATTR matches, and one single instance for most
256 other keys per rule are gone.
258 The NAME assignment is no longer special cased. If later rules assign
259 a NAME value again, the former value will be overwritten. As usual
260 for most other keys, the NAME value can be protected by doing a final
261 assignment with NAME:="<value>".
263 All udev code now uses libudev, which is also exported. The library
264 is still under development, marked as experimental, and its interface
265 may change as long as the DeviceKit integration is not finished.
267 Many thanks to Alan Jenkins for his continuous help, and finding and
268 optimizing some of the computing expensive parts.
274 Kernel devices and device nodes are connected now by reverse indizes in
275 /sys and /dev. A device number retrieved by a stat() or similar, the
276 kernel device directory can be found by looking up:
277 /sys/dev/{block,char}/<maj>:<min>
278 and the device node of the same device by looking up:
279 /dev/{block,char}/<maj>:<min>
283 Fix recently introduced bug, which caused a compilation without large
284 file support, where vol_id does not recognize raid signatures at the end
287 Firewire disks now create both, by-id/scsi-* and by-id/ieee-* links.
288 Seems some kernel versions prevent the creation of the ieee-* links,
289 so people used the scsi-* link which disappeared now.
291 More libudev work. Almost all udevadm functionality comes from libudev
294 udevadm trigger has a new option --type, which allows to trigger events
295 for "devices", for "subsystems", or "failed" devices. The old option
296 --retry-failed" still works, but is no longer mentioned in the man page.
302 The udevadm info --device-id-of-file= output has changed to use
303 the obvious format. Possible current users should use the --export
304 option which is not affected.
306 The old udev commands symlinks to udevadm are not installed, if
307 these symlinks are used, a warning is printed.
313 Optical drive's media is no longer probed for raid signatures,
314 reading the end of the device causes some devices to malfunction.
315 Also the offset of the last session found is used now to probe
318 The volume_id library got a major version number update to 1,
319 some deprecated functions are removed.
321 A shared library "libudev" gets installed now to provide access
322 to udev device information. DeviceKit, the successor of HAL, will
323 need this library to access the udev database and search sysfs for
325 The library is currently in an experimental state, also the API is
326 expected to change, as long as the DeviceKit integration is not
331 We use ./configure now. See INSTALL for details. Current
334 "/usr" - prefix for man pages, include files
336 "" - the root filesystem, prefix for libs and binaries
340 "lib" - directory name for libraries, not a path name
341 multilib 64bit systems may use "lib64" instead of "lib"
343 compile-in verbose debug messages
345 disable all logging and compile-out all log strings
347 link against SELInux libraries, to set the expected context
350 In the default rules, the group "disk" gets permissions 0660 instead
351 of 0640. One small step closer to unify distro rules. Some day, all
352 distros hopefully end up with the same set of rules.
354 No symlinks to udevadm are installed anymore, if they are still needed,
355 they should be provided by the package.
361 Default udev rules, which are not supposed to be edited by the user, should
362 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
363 the udev package and will be replaced with an update. Udev will pick up rule
365 /lib/udev/rules.d/ - default installed rules
366 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
367 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
368 It does not matter in which directory a rule file lives, all files are sorted
371 To help creating /dev/root, we have now:
372 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
375 In case the current --device-id-of-file is already used, please switch to
376 the --export format version, it saves the output parsing and the old
377 format will be changed to use ':' as a separator, like the format in the
382 Fix cdrom_id to properly recognize blank media.
388 Tape drive id-data is queried from /dev/bsg/* instead of the tape
389 nodes. This avoids rewinding tapes on open().
395 The symlinks udevcontrol and udevtrigger are no longer installed by
398 The scsi_id program does not depend on sysfs anymore. It can speak
399 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
400 data, which should solve some old problems with tape devices, where
401 we better do not open all tape device nodes to identify the device.
407 The cdrom_id program is replaced by an advanced version, which can
408 detect most common device types, and also properties of the inserted
409 media. This is part of moving some basic functionality from HAL into
410 udev (and the kernel).
416 The last WAIT_FOR_SYSFS rule is removed from the default rules.
418 The symlinks to udevadm for the debugging tools: udevmonitor and
419 udevtest are no longer created.
421 The symlinks to the udevadm man page for the old tool names are
424 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
425 should be prefixed with '@' to indicate that the path is not a
436 Udevstart is removed from the tree, it did not get installed for
437 a long time now, and is long replaced by trigger and settle.
443 All udev tools are merged into a single binary called udevadm.
444 The old names of the tools are built-in commands in udevadm now.
445 Symlinks to udevadm, with the names of the old tools, provide
446 the same functionality as the standalone tools. There is also
447 only a single udevadm.8 man page left for all tools.
449 Tools like mkinitramfs should be checked, if they need to include
450 udevadm in the list of files.
460 The etc/udev/rules.d/ directory now contains a default set of basic
461 udev rules. This initial version is the result of a rules file merge
462 of Fedora and openSUSE. For these both distros only a few specific
463 rules are left in their own file, named after the distro. Rules which
464 are optionally installed, because they are only valid for a specific
465 architecture, or rules for subsystems which are not always used are
466 in etc/udev/packages/.
472 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
473 actions by dynamically created rules.
475 SYMLINK=="<value>" matches agains the entries in the list of
476 currently defined symlinks. The links are not created in the
477 filesystem at that point in time, but the values can be matched.
479 RUN{ignore_error}+="<program>" will ignore any exit code from the
480 program and not record as a failed event.
486 Final merge of patches/features from the Ubuntu package.
492 Control characters in filesystem label strings are no longer silenty
493 removed, but hex-encoded, to be able to uniquely identify the device
494 by its symlink in /dev/disk/by-label/.
495 If libvolume_id is used by mount(8), LABEL= will work as expected,
496 if slashes or other characters are used in the label string.
498 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
499 can be specified now. The TEST key accepts an optional mode mask
500 TEST{0100}=="<is executable file>".
502 Scsi_id now supports a mode without expecting scsi-specific sysfs
503 entries to allow the extraction of cciss-device persistent properties.
509 In the future, we may see uuid's which are just simple character
510 strings (see the DDF Raid Specification). For that reason vol_id now
511 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
512 the creation of symlinks, the *_SAFE values ensure, that no control
513 or whitespace characters are used in the filename.
515 Possible users of libvolume_id, please use the volume_id_get_* functions.
516 The public struct will go away in a future release of the library.
522 Removal of useless extras/eventrecorder.sh.
532 The directory multiplexer for dev.d/ and hotplug.d are finally removed
533 from the udev package.
539 Symlinks can have priorities now, the priority is assigned to the device
540 and specified with OPTIONS="link_priority=100". Devices with higher
541 priorities overwrite the symlinks of devices with lower priorities.
542 If the device that currently owns the link, goes away, the symlink
543 will be removed, and recreated, pointing to the next device with the
544 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
545 more reliable, if multiple devices contain the same metadata and overwrite
548 The dasd_id program is removed from the udev tree, and dasdinfo, with the
549 needed rules, are part of the s390-tools now.
551 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
552 we may get the scsi sysfs mess fixed some day, and this will only catch
553 the devices we are looking for.
555 USB serial numbers for storage devices have the target:lun now appended,
556 to make it possibble to distinguish broken multi-lun devices with all
557 the same SCSI identifiers.
559 Note: The extra "run_directory" which searches and executes stuff in
560 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
561 with the next release. Make sure, that you don't use it anymore, or
562 provides your own implementation of that inefficient stuff.
563 We are tired of reports about a "slow udev", because these directories
564 contain stuff, that runs with _every_ event, instead of using rules,
565 that run programs only for the matching events.
575 DRIVER== will match only for devices that actually have a real
576 driver. DRIVERS== must be used, if parent devices should be
577 included in the match.
579 Libvolume_id's "linux_raid" detection needed another fix.
587 Add additional check to volume_id detection of via_raid, cause
588 some company decided to put a matching pattern all over the empty
589 storage area of their music players.
593 Fix path_id for SAS devices.
597 The udev daemon can be started with --debug-trace now, which will
598 execute all events serialized to get a chance to catch a possible
599 action that crashes the box.
601 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
602 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
603 are excluded from the warning. Referencing parent attributes directly
604 may break when something in the kernel driver model changes. Udev will
605 just find the attribute by walking up the parent chain.
607 Udevtrigger now sorts the list of devices depending on the device
608 dependency, so a "usb" device is triggered after the parent "pci"
613 Revert persistent-storage ata-serial '_' '-' replacement.
619 Udevtrigger can now filter the list of devices to be triggered. Matches
620 for subsystems or sysfs attributes can be specified.
622 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
623 zero-sized files to avoid pointing to /sys and confuse broken tools which
624 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
627 The rules and scripts to create udev rules for persistent network
628 devices and optical drives are in the extras/rules_generator directory
629 now. If you use something similar, please consider replacing your own
630 version with this, to share the support effort. The rule_generator
631 installs its own rules into /etc/udev/rules.d.
633 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
634 the rule_generator depends on cdrom_id to be called in an earlier rule.
640 Renaming of some key names (the old names still work):
641 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
642 (The behavior of the key DRIVER will change soon in one of the next
643 releases, to match only the event device, please switch to DRIVERS
644 instead. If DRIVER is used, it will behave like DRIVERS, but an error
646 With the new key names, we have a more consistent and simpler scheme.
647 We can match the properties of the event device only, with: KERNEL,
648 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
649 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
650 longer mentioned in the man page and should be switched in the rule
653 ATTR{file}="value" can be used now, to write to a sysfs file of the
654 event device. Instead of:
655 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
657 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
659 All the PHYSDEV* keys are deprecated and will be removed from a
661 PHYDEVPATH - is the path of a parent device and should not be
663 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
664 matched with SUBSYSTEMS==
665 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
666 Newer kernels will have DRIVER in the environment,
667 for older kernels udev puts in. Class device will
668 no longer carry this property of a parent and
669 DRIVERS== can be used to match such a parent value.
670 Note that ENV{DRIVER} is only available for a few bus devices, where
671 the driver is already bound at device event time. On coldplug, the
672 events for a lot devices are already bound to a driver, and they will have
673 that value set. But on hotplug, at the time the kernel creates the device,
674 it can't know what driver may claim the device after that, therefore
675 in most cases it will be empty.
677 Failed events should now be re-triggered with:
678 udevtrigger --retry-failed.
679 Please switch to this command, so we keep the details of the /dev/.udev/failed/
680 files private to the udev tools. We may need to switch the current symlink
681 target, cause some obviously broken tools try to scan all files in /dev
682 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
683 million times. This takes ages on slow boxes.
685 The udevinfo attribute walk (-a) now works with giving a device node
686 name (-n) instead of a devpath (-p). The query now always works, also when
687 no database file was created by udev.
689 The built-in /etc/passwd /etc/group parser is removed, we always depend on
690 getpwnam() and getgrnam() now. One of the next releases will depend on
691 fnmatch() and may use getopt_long().
695 Bugfixes and small improvements.
699 Fix path_id for recent kernels.
705 Added support for swapping network interface names, by temporarily
706 renaming the device and wait for the target name to become free.
710 The built-in MODALIAS key and substitution is removed.
714 The binary firmware helper is replaced by the usual simple
715 shell script. Udevsend is removed from the tree.
723 Some more keys require the correct use of '==' and '=' depending
724 on the kind of operation beeing an assignment or a match. Rules
725 with invalid operations are skipped and logged to syslog. Please
726 test with udevtest if the parsing of your rules throws errors and
727 fix possibly broken rules.
731 Provide "udevsettle" to wait for all current udev events to finish.
732 It also watches the current kernel netlink queue by comparing the
733 even sequence number to make sure that there are no current pending
734 events that have not already arrived in the daemon.
738 Fix rule to skip persistent rules for removable IDE devices, which
739 also skipped optical IDE drives.
741 All *_id program are installed in /lib/udev/ by default now.
743 No binary is stripped anymore as this should be done in the
744 packaging process and not at build time.
746 libvolume_id is provided as a shared library now and vol_id is
747 linked against it. Also one of the next HAL versions will require
748 this library, and the HAL build process will also require the
749 header file to be installed. The copy of the same code in HAL will
750 be removed to have only a single copy left on the system.
754 Add persistent links for SCSI tapes. The rules file is renamed
755 to 60-persistent-storage.rules.
757 Create persistent path for usb devices. Can be used for all sorts
758 of devices that can't be distinguished by other properties like
759 multiple identical keyboards and mice connected to the same box.
761 Provide "udevtrigger" program to request events on coldplug. The
762 shell script is much too slow with thousends of devices.
766 Fix persistent disk rules to exclude removable IDE drives.
768 Warn if %e, $modalias or MODALIAS is used.
772 Fix queue export, which wasn't correct for subsequent add/remove
773 events for the same device.
777 Fix cramfs detection on big endian.
779 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
784 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
785 attributes were only checked at the parent device that matched the
786 by BUS requested subsystem. Fix it to also look at the device we
787 received the event for.
789 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
794 Fix a bug where NAME="" would prevent RUN from beeing executed.
796 RUN="/bin/program" does not longer automatically add the subsystem
797 as the first parameter. This is from the days of /sbin/hotplug
798 which is dead now and it's just confusing to need to add a space at
799 the end of the program name to prevent this.
800 If you use rules that need the subsystem as the first parameter,
801 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
802 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
806 The udev man page has moved to udev(7) as it does not describe a command
807 anymore. The programs udev, udevstart and udevsend are no longer installed
808 by default and must be copied manually, if they should be installed or
809 included in a package.
811 Fix a bug where "ignore_device" could run earlier collected RUN keys before
812 the ignore rule was applied.
814 More preparation for future sysfs changes. usb_id and scsi_id no longer
815 depend on a magic order of devices in the /devices chain. Specific devices
816 should be requested by their subsytem.
818 This will always find the scsi parent device without depending on a specific
820 dev = sysfs_device_get(devpath);
821 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
823 The "device" link in the current sysfs layout will be automatically
824 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
825 parent in the devpath. If a device is requested by it's symlink, like all
826 class devices in the new sysfs layout will look like, it gets automatically
827 resolved and substituted with the real devpath and not the symlink path.
830 A similar logic must be applied to _all_ sysfs users, including
831 scripts, that search along parent devices in sysfs. The explicit use of
832 the "device" link must be avoided. With the future sysfs layout all
833 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
834 back to the "class" or the "bus". The layout of the parent devices in
835 /devices is not necessarily expected to be stable across kernel releases and
836 searching for parents by their subsystem should make sysfs users tolerant
837 for changed parent chains.
841 Prepare udev to work with the experimental kernel patch, that moves
842 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
844 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
845 moving the class devices to /sys/devices.
847 Thanks again to Marco for help finding a hopefully nice compromise
848 to make %b simpler and working again.
852 Complete removal of libsysfs, replaced by simple helper functions
853 which are much simpler and a bit faster. The udev daemon operatesentirely
854 on event parameters and does not use sysfs for simple rules anymore.
855 Please report any new bugs/problems, that may be caused by this big
856 change. They will be fixed immediately.
858 The enumeration format character '%e' is deprecated and will be
859 removed sometimes from a future udev version. It never worked correctly
860 outside of udevstart, so we can't use it with the new parallel
861 coldplug. A simple enumeration is as useless as the devfs naming
862 scheme, just get rid of both if you still use it.
864 MODALIAS and $modalias is not needed and will be removed from one of
865 the next udev versions, replace it in all rules with ENV{MODALIAS} or
866 the sysfs "modalias" value.
868 Thanks a lot to Marco for all his help on finding and fixing bugs.
872 Let scsi_id request libata drive serial numbers from page 0x80.
874 Renamed etc/udev/persistent.rules to persistent-disk.rules and
875 added /dev/disk/by-name/* for device mapper device names.
877 Removed %e from the man page. It never worked reliably outside
878 of udevstart and udevstart is no longer recommended to use.
882 Symlinks are now exported to the event environment. Hopefully it's no
883 longer needed to run udevinfo from an event process, like it was
884 mentioned on the hotplug list:
885 UDEV [1134776873.702967] add@/block/sdb
888 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
892 Fix a problem if udevsend is used as the hotplug handler and tries to use
893 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
894 and this kind of problems will hopefully go away soon.
898 All built-in logic to work around bad sysfs timing is removed with this
899 version. The need to wait for sysfs files is almost fixed with a kernel
900 version that doesn't work with this udev version anyway. Until we fix
901 the timing of the "bus" link creation, the former integrated logic should
902 be emulated by a rule placed before all other rules:
903 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
905 The option "udev_db" does no longer exist. All udev state will be in
906 /$udev_root/.udev/ now, there is no longer an option to set this
908 If the init script or something else used this value, just depend on
909 this hardcoded path. But remember _all_content_ of this directory is
910 still private to udev and can change at any time.
912 Default location for rule sripts and helper programs is now: /lib/udev/.
913 Everything that is not useful on the commandline should go into this
914 directory. Some of the helpers in the extras folder are installed there
915 now. The rules need to be changed, to find the helpers there.
917 Also /lib/udev/devices is recommended as a directory where packages or
918 the user can place real device nodes, which get copied over to /dev at
919 every boot. This should replace the various solutions with custom config
922 Udevsend does no longer start the udev daemon. This must be done with
923 the init script that prepares /dev on tmpfs and creates the initial nodes,
924 before starting the daemon.
928 Silent a too verbose error logging for the old hotplug.d/ dev.d/
931 The copy of klibc is removed. A systemwide installed version of klibc
932 should be used to build a klibc udev now.
936 NAME="" will not create any nodes, but execute RUN keys. To completely
937 ignore an event the OPTION "ignore_device" should be used.
939 After removal of the reorder queue, events with a TIMEOUT can be executed
940 without any queuing now.
944 Fixed bug in udevd, if inotify is not available. We depend on netlink
945 uevents now, kernels without that event source will not work with that
946 version of udev anymore.
950 The rule parsing happens now in the daemon once at startup, all udev
951 event processes inherit the already parsed rules from the daemon.
952 It is shipped with SUSE10.0 and reduces heavily the system load at
953 startup. The option to save precompiled rules and let the udev process
954 pick the them up is removed, as it's no longer needed.
956 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
957 device. Libsysfs is changed to "translate" the requested link into the
958 real device path, as it would happen with the hotplug event. Otherwise
959 device removal and the udev database will not work.
961 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
964 A few improvements for vol_id, the filesytem probing code.
968 Fix a stupid typo in extras/run_directory for "make install".
970 scsi_id creates the temporary devnode now in /dev for usage with a
971 non-writable /tmp directory.
973 The uevent kernel socket buffer can carry app. 50.000 events now,
974 let's see who can break this again. :)
976 The upcoming kernel will have a new input driver core integration.
977 Some class devices are now symlinks to the real device. libsysfs
978 needs a fix for this to work correctly. Udevstart of older udev
979 versions will _not_ create these devices!
983 Fix a 'install' target in the Makefile, that prevents EXTRAS from
988 A bunch of mostly trivial bugfixes. From now on no node name or
989 symlink name can contain any character than plain whitelisted ascii
990 characters or validated utf8 byte-streams. This is needed for the
991 /dev/disk/by-label/* links, because we import untrusted data and
992 export it to the filesystem.
996 More bugfixes. If udevd was started from the kernel, we don't
997 have stdin/stdout/stderr, which broke the forked tools in some
1002 Bugfix. udevstart event ordering was broken for a long time.
1003 The new run_program() uncovered it, because /dev/null was not
1004 available while we try to run external programs.
1005 Now udevstart should create it before we run anything.
1009 Minor bugfixes and some distro rules updates. If you don't have the
1010 persistent disk rules in /dev/disk/by-*/* on your distro, just
1011 grab it from here. :)
1015 We can use socket communication now to pass events from udev to
1017 RUN+="socket:/org/freedesktop/hal/udev_event"
1018 will pass the whole udev event to the HAL daemon without the need
1019 for a forked helper. (See ChangeLog for udevmonitor, as an example)
1023 Mostly bugfixes and see ChangeLog.
1025 The test for the existence of an environment value should be
1027 ENV{KEY}=="*" to ENV{KEY}=="?*"
1028 because "*" will not fail anymore, if the key does not exist or
1033 Bugfixes and a few tweaks described in the ChangeLog.
1037 Mostly a Bugfix release.
1039 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
1040 timing with custom rules.
1044 We changed the internal rule storage format. Our large rule files took
1045 2 MB of RAM, with the change we are down to 99kB.
1047 If the device-node has been created with default name and no symlink or
1048 options are to remenber, it is not longer stored in the udevdb. HAL will
1049 need to be updated to work correctly with that change.
1051 To overrride optimization flags, OPTFLAGS may be used now.
1059 Major changes happened with this release. The goal is to take over the
1060 complete kernel-event handling and provide a more efficient way to dispatch
1061 kernel events. Replacing most of the current shell script logic and the
1062 kernel forked helper with a netlink-daemon and a rule-based event handling.
1064 o udevd listens to netlink events now. The first valid netlink event
1065 will make udevd ignore any message from udevsend that contains a
1066 SEQNUM, to avoid duplicate events. The forked events can be disabled
1068 echo "" > /proc/sys/kernel/hotplug
1069 For full support, the broken input-subsytem needs to be fixed, not to
1070 bypass the driver core.
1072 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
1073 removed from udev itself and must be emulated by calling small
1074 helper binaries provided in the extras folder:
1075 make EXTRAS=extras/run_directory/
1076 will build udev_run_devd and udev_run_hotplugd, which can be called
1077 from a rule if needed:
1078 RUN+="/sbin/udev_run_hotplugd"
1079 The recommended way to handle this is to convert all the calls from
1080 the directories to explicit udev rules and get completely rid of the
1081 multiplexing. (To catch a ttyUSB event, you now no longer need to
1082 fork and exit 300 tty script instances you are not interested in, it
1083 is just one rule that matches exactly the device.)
1085 o udev handles now _all_ events not just events for class and block
1086 devices, this way it is possible to control the complete event
1087 behavior with udev rules. Especially useful for rules like:
1088 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
1090 o As used in the modalias rule, udev supports now textual
1091 substitution placeholder along with the usual format chars. This
1092 needs to be documented, for now it's only visible in udev_rules_parse.c.
1094 o The rule keys support now more operations. This is documented in the
1095 man page. It is possible to add values to list-keys like the SYMLINK
1096 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
1097 Also "final"-assignments are supported by using KEY:="value", which will
1098 prevent changing the key by any later rule.
1100 o kernel 2.6.12 has the "detached_state" attribute removed from
1101 sysfs, which was used to recognize sysfs population. We switched that
1102 to wait for the "bus" link, which is only available in kernels after 2.6.11.
1103 Running this udev version on older kernels may cause a short delay for
1106 o To provide infrastructure for persistent device naming, the id programs:
1107 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
1108 to export the probed data in environment key format:
1109 pim:~ # /sbin/ata_id --export /dev/hda
1110 ID_MODEL=HTS726060M9AT00
1111 ID_SERIAL=MRH401M4G6UM9B
1112 ID_REVISION=MH4OA6BA
1114 The following rules:
1115 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
1116 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
1119 kay@pim:~> tree /dev/disk
1122 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
1123 | `-- IBM-Memory_Key -> ../../sda
1125 | |-- swap -> ../../hda1
1126 | |-- date -> ../../sda1
1127 | `-- home -> ../../hda3
1129 |-- 2E08712B0870F2E7 -> ../../hda3
1130 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
1131 |-- E845-7A89 -> ../../sda1
1132 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
1134 The IMPORT= operation will import these keys in the environment and make
1135 it available for later PROGRAM= and RUN= executed programs. The keys are
1136 also stored in the udevdb and can be queried from there with one of the
1139 o A few binaries are silently added to the repository, which can be used
1140 to replay kernel events from initramfs instead of using coldplug. udevd
1141 can be instructed now to queue-up events while the stored events from
1142 initramfs are filled into the udevd-queue. This code is still under
1143 development and there is no documentation now besides the code itself.
1144 The additional binaries get compiled, but are not installed by default.
1146 o There is also a temporary fix for a performance problem where too many
1147 events happen in parallel and every event needs to parse the rules.
1148 udev can now read precompiled rules stored on disk. This is likely to be
1149 replaced by a more elegant solution in a future udev version.
1153 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
1154 Fix for libsysfs not to expect this file was added.
1158 All rules are applied now, but only the first matching rule with a NAME-key
1159 will be applied. All later rules with NAME-key are completely ignored. This
1160 way system supplied symlinks or permissions gets applied to user-defined
1164 Please check your rules setup, if you may need to add OPTIONS="last_rule"
1165 to some rules, to keep the old behavior.
1167 The rules are read on "remove"-events too. That makes is possible to match
1168 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
1169 instruct udev to ignore an event (OPTIONS="ignore_device").
1170 The new ACTION-key may be used to let a rule act only at a "remove"-event.
1172 The new RUN-key supports rule-based execution of programs after device-node
1173 handling. This is meant as a general replacement for the dev.d/-directories
1174 to give fine grained control over the execution of programs.
1176 The %s{}-sysfs format char replacement values are searched at any of the
1177 devices in the device chain now, not only at the class-device.
1179 We support log priority levels now. The value udev_log in udev.conf is used
1180 to determine what is printed to syslog. This makes it possible to
1181 run a version with compiled-in debug messages in a production environment
1182 which is sometimes needed to find a bug.
1183 It is still possible to supress the inclusion of _any_ syslog usage with
1184 USE_LOG=false to create the smallest possible binaries if needed.
1185 The configured udev_log value can be overridden with the environment variable
1190 Possible use of a system-wide klibc:
1191 make USE_KLIBC=true KLCC=/usr/bin/klcc all
1192 will link against an external klibc and our own version will be ignored.
1196 We support an unlimited count of symlinks now.
1198 If USE_STATIC=true is passed to a glibc build, we link statically and use
1199 a built-in userdb parser to resolve user and group names.
1201 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
1202 we walk up the chain of physical devices to find a match.
1204 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
1205 easy to skip certain attribute matches without composing rules with weird
1206 character class negations like:
1207 KERNEL="[!s][!c][!d]*"
1208 this can now be replaced with:
1210 The current simple '=' is still supported, and should work as it does today,
1211 but existing rules should be converted if possible, to be better readable.
1213 We have new ENV{}== key now, to match against a maximum of 5 environment
1216 udevstart is its own binary again, because we don't need co carry this araound
1217 with every forked event.
~ianmdlvl / elogind.git / blob