9 The udevadm trigger "--retry-failed" option, which is replaced since quite
10 a while by "--type=failed" is removed.
12 The failed tracking was not working at all for a few releases. The RUN
13 option "ignore_error" is replaced by a "fail_event_on_error" option, and the
14 default is not to track any failing RUN executions.
16 New keymaps, new modem, hid2hci updated.
20 Fix possible crash in udevd when worker processes are busy, rules are
21 changed at the same time, and workers get killed to reload the rules.
27 Properties set with ENV{.FOO}="bar" are marked private by starting the
28 name with a '.'. They will not be stored in the database, and not be
29 exported with the event.
31 Firmware files are looked up in:
32 /lib/firmware/updates/$(uname -r)
34 /lib/firmware/$(uname -r)
38 ATA devices switched the property from ID_BUS=scsi to ID_BUS=ata.
39 ata_id, instead of scsi_id, is the default tool now for ATA devices.
45 The configure options have changed because another library needs to be
46 installed in a different location. Instead of exec_prefix and udev_prefix,
47 libdir, rootlibdir and libexecdir are used. The Details are explained in
50 Event processes now get re-used after they handled an event. This reduces
51 the number of forks and the pressure on the CPU significantly, because
52 cloned event processes no longer cause page faults in the main daemon.
53 After the events have settled, a few worker processes stay around for
54 future events, all others get cleaned up.
56 To be able to use signalfd(), udev depends on kernel version 2.6.25 now.
57 Also inotify support is mandatory now to run udev.
59 The format of the queue exported by the udev damon has changed. There is
60 no longer a /dev/.udev/queue/ directory. The current event queue can be
61 accessed with udevadm settle and libudedv.
63 Libudev does not have the unstable API header anymore. From now on,
64 incompatible changes will be handled by bumping the library major version.
66 To build udev from the git tree gtk-doc is needed now. The tarballs will
67 build without it and contain the pre-built documentation. An online copy
69 http://www.kernel.org/pub/linux/utils/kernel/hotplug/libudev/
71 The tools from the udev-extras repository have been merged into the main
72 udev repository. Some of the extras have larger external dependencies, and
73 they can be disabled with the configure switch --disable-extras.
79 The program vol_id and the library libvolume_id are removed from the
80 repository. Libvolume_id is merged with libblkid from the util-linux-ng
81 package. Persistent disk links for label and uuid depend on the
82 util-linux-ng version (2.15) of blkid now. Older versions of blkid
83 can not be used with udev.
85 Libudev allows to subscribe to udev events. To prevent unwanted messages
86 to be delivered, and waking up the subscribing process, a filter can be
87 installed, to drop messages inside a kernel socket filter. The filters
88 match on the <subsytem>:<devtype> properties of the device.
89 This is part of the ongoing effort to replace HAL, and switch current
90 users over to directly use libudev.
91 Libudev is still marked as experimental, and its interface might
92 eventually change if needed, but no major changes of the currently exported
93 interface are expected anymore, and a first stable release should happen
96 A too old kernel (2.6.21) or a kernel with CONFIG_SYSFS_DEPRECATED
97 is not supported since while and udevd will log an error message at
98 startup. It should still be able to boot-up, but advanced rules and system
99 services which depend on the information not available in the old sysfs
100 format will fail to work correctly.
102 DVB device naming is supplied by the kernel now. In case older kernels
103 need to be supported, the old shell script should be added to a compat
110 The processed udev events get send back to the netlink socket. Libudev
111 provides access to these events. This is work-in-progress, to replace
112 the DeviceKit daemon functionality directly with libudev. There are
113 upcoming kernel changes to allow non-root users to subcribe to these
120 "udevadm settle" now optionally accepts a range of events to wait for,
121 instead of waiting for "all" events.
127 The installed watch for block device metadata changes is now removed
128 during event hadling, because some (broken) tools may be called from udev
129 rules and (wrongly) open the device with write access. After the finished
130 event handling the watch is restored.
136 Device nodes can be watched for changes with inotify with OPTIONS="watch".
137 If closed after being opened for writing, a "change" uevent will occur.
138 /dev/disk/by-{label,uuid}/* symlinks will be automatically updated.
144 The udevadm test command has no longer a --force option, nodes and symlinks
145 are always updated with a test run now.
147 The udevd daemon can be started with --resolve-names=never to avoid all user
148 and group lookups (e.g. in cut-down systems) or --resolve-names=late to
149 lookup user and groups every time events are handled.
155 We are currently merging the Ubuntu rules in the udev default rules,
156 and get one step closer to provide a common Linux /dev setup, regarding
157 device names, symlinks, and default device permissions. On udev startup,
158 we now expect the following groups to be resolvable to their ids with
160 disk, cdrom, floppy, tape, audio, video, lp, tty, dialout, kmem.
161 LDAP setups need to make sure, that these groups are always resolvable at
162 bootup, with only the rootfs mounted, and without network access available.
164 Some systems may need to add some new, currently not used groups, or need
165 to add some users to new groups, but the cost of this change is minimal,
166 compared to the pain the current, rather random, differences between the
167 various distributions cause for upstream projects and third-party vendors.
169 In general, "normal" users who log into a machine should never be a member
170 of any such group, but the device-access should be managed by dynamic ACLs,
171 which get added and removed for the specific users on login/logout and
172 session activity/inactivity. These groups are only provided for custom setups,
173 and mainly system services, to allow proper privilege separation.
174 A video-streaming daemon uid would be a member of "audio" and "video", to get
175 access to the sound and video devices, but no "normal" user should ever belong
176 to the "audio" group, because he could listen to the built-in microphone with
177 any ssh-session established from the other side of the world.
179 /dev/serial/by-{id,path}/ now contains links for ttyUSB devices,
180 which do not depend on the kernel device name. As usual, unique
181 devices - only a single one per product connected, or a real
182 USB serial number in the device - are always found with the same
183 name in the by-id/ directory.
184 Completely identical devices may overwrite their names in by-id/
185 and can only be found reliably in the by-path/ directory. Devices
186 specified by by-path/ must not change their connection, like the
187 USB port number they are plugged in, to keep their name.
189 To support some advanced features, Linux 2.6.22 is the oldest supported
190 version now. The kernel config with enabled SYSFS_DEPRECATED is no longer
191 supported. Older kernels should still work, and devices nodes should be
192 reliably created, but some rules and libudev will not work correctly because
193 the old kernels do not provide the expected information or interfaces.
199 Fix for a possible segfault while swapping network interface names in udev
206 The group "video" is part of the default rules now.
210 Bugfix for kernels using SYSFS_DEPRECATED* option and finding parent
211 block devices in some cases. No common distro uses this option anymore,
212 and we do not get enough testing for this and recent udev versions. If
213 this option is not needed to run some old distro with a new kernel,
214 it should be disabled in the kernel config.
216 Bugfix for the $links substitution variable, which may crash if no links
217 are created. This should not happen in usual setups because we always
218 create /dev/{block,char}/ links.
220 The strings of the parsed rules, which are kept in memory, no longer
221 contain duplicate entries, or duplicate tails of strings. This, and the
222 new rules parsing/matching code reduces the total in-memory size of
223 a huge distro rule sets to 0.08 MB, compared to the 1.2MB of udev
226 The export of DEVTYPE=disk/partition got removed from the default
227 rules. This value is available from the kernel. The pnp shell script
228 modprobe hack is removed from the default rules. ACPI devices have _proper_
229 modalias support and take care of the same functionality.
230 Installations which support old kernels, but install current default
231 udev rules may want to add that to the compat rules file.
233 Libvolume_id now always probes for all known filesystems, and does not
234 stop at the first match. Some filesystems are marked as "exclusive probe",
235 and if any other filesytem type matches at the same time, libvolume_id
236 will, by default, not return any probing result. This is intended to prevent
237 mis-detection with conflicting left-over signatures found from earlier
238 file system formats. That way, we no longer depend on the probe-order
239 in case of multiple competing signatures. In some setups the kernel allows
240 to mount a volume with just the old filesystem signature still in place.
241 This may damage the new filesystem and cause data-loss, just by mounting
242 it. Because volume_id can not decide which one the correct signature is,
243 the wrong signatures need to be removed manually from the volume, or the
244 volume needs to be reformatted, to enable filesystem detection and possible
249 Fix segfault if compiled without optimization and dbg() does not get
250 compiled out and uses variables which are not available.
254 Bugfixes. (And maybe new bugs. :))
256 The rule matching engine got converted from a rule list to a token
257 array which reduced the in-memory rules representation of a full
258 featured distros with thousends of udev rules from 1.2MB to 0.12 MB.
259 Limits like 5 ENV and ATTR matches, and one single instance for most
260 other keys per rule are gone.
262 The NAME assignment is no longer special cased. If later rules assign
263 a NAME value again, the former value will be overwritten. As usual
264 for most other keys, the NAME value can be protected by doing a final
265 assignment with NAME:="<value>".
267 All udev code now uses libudev, which is also exported. The library
268 is still under development, marked as experimental, and its interface
269 may change as long as the DeviceKit integration is not finished.
271 Many thanks to Alan Jenkins for his continuous help, and finding and
272 optimizing some of the computing expensive parts.
278 Kernel devices and device nodes are connected now by reverse indizes in
279 /sys and /dev. A device number retrieved by a stat() or similar, the
280 kernel device directory can be found by looking up:
281 /sys/dev/{block,char}/<maj>:<min>
282 and the device node of the same device by looking up:
283 /dev/{block,char}/<maj>:<min>
287 Fix recently introduced bug, which caused a compilation without large
288 file support, where vol_id does not recognize raid signatures at the end
291 Firewire disks now create both, by-id/scsi-* and by-id/ieee-* links.
292 Seems some kernel versions prevent the creation of the ieee-* links,
293 so people used the scsi-* link which disappeared now.
295 More libudev work. Almost all udevadm functionality comes from libudev
298 udevadm trigger has a new option --type, which allows to trigger events
299 for "devices", for "subsystems", or "failed" devices. The old option
300 --retry-failed" still works, but is no longer mentioned in the man page.
306 The udevadm info --device-id-of-file= output has changed to use
307 the obvious format. Possible current users should use the --export
308 option which is not affected.
310 The old udev commands symlinks to udevadm are not installed, if
311 these symlinks are used, a warning is printed.
317 Optical drive's media is no longer probed for raid signatures,
318 reading the end of the device causes some devices to malfunction.
319 Also the offset of the last session found is used now to probe
322 The volume_id library got a major version number update to 1,
323 some deprecated functions are removed.
325 A shared library "libudev" gets installed now to provide access
326 to udev device information. DeviceKit, the successor of HAL, will
327 need this library to access the udev database and search sysfs for
329 The library is currently in an experimental state, also the API is
330 expected to change, as long as the DeviceKit integration is not
335 We use ./configure now. See INSTALL for details. Current
338 "/usr" - prefix for man pages, include files
340 "" - the root filesystem, prefix for libs and binaries
344 "lib" - directory name for libraries, not a path name
345 multilib 64bit systems may use "lib64" instead of "lib"
347 compile-in verbose debug messages
349 disable all logging and compile-out all log strings
351 link against SELInux libraries, to set the expected context
354 In the default rules, the group "disk" gets permissions 0660 instead
355 of 0640. One small step closer to unify distro rules. Some day, all
356 distros hopefully end up with the same set of rules.
358 No symlinks to udevadm are installed anymore, if they are still needed,
359 they should be provided by the package.
365 Default udev rules, which are not supposed to be edited by the user, should
366 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
367 the udev package and will be replaced with an update. Udev will pick up rule
369 /lib/udev/rules.d/ - default installed rules
370 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
371 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
372 It does not matter in which directory a rule file lives, all files are sorted
375 To help creating /dev/root, we have now:
376 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
379 In case the current --device-id-of-file is already used, please switch to
380 the --export format version, it saves the output parsing and the old
381 format will be changed to use ':' as a separator, like the format in the
386 Fix cdrom_id to properly recognize blank media.
392 Tape drive id-data is queried from /dev/bsg/* instead of the tape
393 nodes. This avoids rewinding tapes on open().
399 The symlinks udevcontrol and udevtrigger are no longer installed by
402 The scsi_id program does not depend on sysfs anymore. It can speak
403 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
404 data, which should solve some old problems with tape devices, where
405 we better do not open all tape device nodes to identify the device.
411 The cdrom_id program is replaced by an advanced version, which can
412 detect most common device types, and also properties of the inserted
413 media. This is part of moving some basic functionality from HAL into
414 udev (and the kernel).
420 The last WAIT_FOR_SYSFS rule is removed from the default rules.
422 The symlinks to udevadm for the debugging tools: udevmonitor and
423 udevtest are no longer created.
425 The symlinks to the udevadm man page for the old tool names are
428 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
429 should be prefixed with '@' to indicate that the path is not a
440 Udevstart is removed from the tree, it did not get installed for
441 a long time now, and is long replaced by trigger and settle.
447 All udev tools are merged into a single binary called udevadm.
448 The old names of the tools are built-in commands in udevadm now.
449 Symlinks to udevadm, with the names of the old tools, provide
450 the same functionality as the standalone tools. There is also
451 only a single udevadm.8 man page left for all tools.
453 Tools like mkinitramfs should be checked, if they need to include
454 udevadm in the list of files.
464 The etc/udev/rules.d/ directory now contains a default set of basic
465 udev rules. This initial version is the result of a rules file merge
466 of Fedora and openSUSE. For these both distros only a few specific
467 rules are left in their own file, named after the distro. Rules which
468 are optionally installed, because they are only valid for a specific
469 architecture, or rules for subsystems which are not always used are
470 in etc/udev/packages/.
476 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
477 actions by dynamically created rules.
479 SYMLINK=="<value>" matches agains the entries in the list of
480 currently defined symlinks. The links are not created in the
481 filesystem at that point in time, but the values can be matched.
483 RUN{ignore_error}+="<program>" will ignore any exit code from the
484 program and not record as a failed event.
490 Final merge of patches/features from the Ubuntu package.
496 Control characters in filesystem label strings are no longer silenty
497 removed, but hex-encoded, to be able to uniquely identify the device
498 by its symlink in /dev/disk/by-label/.
499 If libvolume_id is used by mount(8), LABEL= will work as expected,
500 if slashes or other characters are used in the label string.
502 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
503 can be specified now. The TEST key accepts an optional mode mask
504 TEST{0100}=="<is executable file>".
506 Scsi_id now supports a mode without expecting scsi-specific sysfs
507 entries to allow the extraction of cciss-device persistent properties.
513 In the future, we may see uuid's which are just simple character
514 strings (see the DDF Raid Specification). For that reason vol_id now
515 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
516 the creation of symlinks, the *_SAFE values ensure, that no control
517 or whitespace characters are used in the filename.
519 Possible users of libvolume_id, please use the volume_id_get_* functions.
520 The public struct will go away in a future release of the library.
526 Removal of useless extras/eventrecorder.sh.
536 The directory multiplexer for dev.d/ and hotplug.d are finally removed
537 from the udev package.
543 Symlinks can have priorities now, the priority is assigned to the device
544 and specified with OPTIONS="link_priority=100". Devices with higher
545 priorities overwrite the symlinks of devices with lower priorities.
546 If the device that currently owns the link, goes away, the symlink
547 will be removed, and recreated, pointing to the next device with the
548 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
549 more reliable, if multiple devices contain the same metadata and overwrite
552 The dasd_id program is removed from the udev tree, and dasdinfo, with the
553 needed rules, are part of the s390-tools now.
555 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
556 we may get the scsi sysfs mess fixed some day, and this will only catch
557 the devices we are looking for.
559 USB serial numbers for storage devices have the target:lun now appended,
560 to make it possibble to distinguish broken multi-lun devices with all
561 the same SCSI identifiers.
563 Note: The extra "run_directory" which searches and executes stuff in
564 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
565 with the next release. Make sure, that you don't use it anymore, or
566 provides your own implementation of that inefficient stuff.
567 We are tired of reports about a "slow udev", because these directories
568 contain stuff, that runs with _every_ event, instead of using rules,
569 that run programs only for the matching events.
579 DRIVER== will match only for devices that actually have a real
580 driver. DRIVERS== must be used, if parent devices should be
581 included in the match.
583 Libvolume_id's "linux_raid" detection needed another fix.
591 Add additional check to volume_id detection of via_raid, cause
592 some company decided to put a matching pattern all over the empty
593 storage area of their music players.
597 Fix path_id for SAS devices.
601 The udev daemon can be started with --debug-trace now, which will
602 execute all events serialized to get a chance to catch a possible
603 action that crashes the box.
605 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
606 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
607 are excluded from the warning. Referencing parent attributes directly
608 may break when something in the kernel driver model changes. Udev will
609 just find the attribute by walking up the parent chain.
611 Udevtrigger now sorts the list of devices depending on the device
612 dependency, so a "usb" device is triggered after the parent "pci"
617 Revert persistent-storage ata-serial '_' '-' replacement.
623 Udevtrigger can now filter the list of devices to be triggered. Matches
624 for subsystems or sysfs attributes can be specified.
626 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
627 zero-sized files to avoid pointing to /sys and confuse broken tools which
628 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
631 The rules and scripts to create udev rules for persistent network
632 devices and optical drives are in the extras/rules_generator directory
633 now. If you use something similar, please consider replacing your own
634 version with this, to share the support effort. The rule_generator
635 installs its own rules into /etc/udev/rules.d.
637 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
638 the rule_generator depends on cdrom_id to be called in an earlier rule.
644 Renaming of some key names (the old names still work):
645 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
646 (The behavior of the key DRIVER will change soon in one of the next
647 releases, to match only the event device, please switch to DRIVERS
648 instead. If DRIVER is used, it will behave like DRIVERS, but an error
650 With the new key names, we have a more consistent and simpler scheme.
651 We can match the properties of the event device only, with: KERNEL,
652 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
653 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
654 longer mentioned in the man page and should be switched in the rule
657 ATTR{file}="value" can be used now, to write to a sysfs file of the
658 event device. Instead of:
659 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
661 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
663 All the PHYSDEV* keys are deprecated and will be removed from a
665 PHYDEVPATH - is the path of a parent device and should not be
667 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
668 matched with SUBSYSTEMS==
669 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
670 Newer kernels will have DRIVER in the environment,
671 for older kernels udev puts in. Class device will
672 no longer carry this property of a parent and
673 DRIVERS== can be used to match such a parent value.
674 Note that ENV{DRIVER} is only available for a few bus devices, where
675 the driver is already bound at device event time. On coldplug, the
676 events for a lot devices are already bound to a driver, and they will have
677 that value set. But on hotplug, at the time the kernel creates the device,
678 it can't know what driver may claim the device after that, therefore
679 in most cases it will be empty.
681 Failed events should now be re-triggered with:
682 udevtrigger --retry-failed.
683 Please switch to this command, so we keep the details of the /dev/.udev/failed/
684 files private to the udev tools. We may need to switch the current symlink
685 target, cause some obviously broken tools try to scan all files in /dev
686 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
687 million times. This takes ages on slow boxes.
689 The udevinfo attribute walk (-a) now works with giving a device node
690 name (-n) instead of a devpath (-p). The query now always works, also when
691 no database file was created by udev.
693 The built-in /etc/passwd /etc/group parser is removed, we always depend on
694 getpwnam() and getgrnam() now. One of the next releases will depend on
695 fnmatch() and may use getopt_long().
699 Bugfixes and small improvements.
703 Fix path_id for recent kernels.
709 Added support for swapping network interface names, by temporarily
710 renaming the device and wait for the target name to become free.
714 The built-in MODALIAS key and substitution is removed.
718 The binary firmware helper is replaced by the usual simple
719 shell script. Udevsend is removed from the tree.
727 Some more keys require the correct use of '==' and '=' depending
728 on the kind of operation beeing an assignment or a match. Rules
729 with invalid operations are skipped and logged to syslog. Please
730 test with udevtest if the parsing of your rules throws errors and
731 fix possibly broken rules.
735 Provide "udevsettle" to wait for all current udev events to finish.
736 It also watches the current kernel netlink queue by comparing the
737 even sequence number to make sure that there are no current pending
738 events that have not already arrived in the daemon.
742 Fix rule to skip persistent rules for removable IDE devices, which
743 also skipped optical IDE drives.
745 All *_id program are installed in /lib/udev/ by default now.
747 No binary is stripped anymore as this should be done in the
748 packaging process and not at build time.
750 libvolume_id is provided as a shared library now and vol_id is
751 linked against it. Also one of the next HAL versions will require
752 this library, and the HAL build process will also require the
753 header file to be installed. The copy of the same code in HAL will
754 be removed to have only a single copy left on the system.
758 Add persistent links for SCSI tapes. The rules file is renamed
759 to 60-persistent-storage.rules.
761 Create persistent path for usb devices. Can be used for all sorts
762 of devices that can't be distinguished by other properties like
763 multiple identical keyboards and mice connected to the same box.
765 Provide "udevtrigger" program to request events on coldplug. The
766 shell script is much too slow with thousends of devices.
770 Fix persistent disk rules to exclude removable IDE drives.
772 Warn if %e, $modalias or MODALIAS is used.
776 Fix queue export, which wasn't correct for subsequent add/remove
777 events for the same device.
781 Fix cramfs detection on big endian.
783 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
788 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
789 attributes were only checked at the parent device that matched the
790 by BUS requested subsystem. Fix it to also look at the device we
791 received the event for.
793 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
798 Fix a bug where NAME="" would prevent RUN from beeing executed.
800 RUN="/bin/program" does not longer automatically add the subsystem
801 as the first parameter. This is from the days of /sbin/hotplug
802 which is dead now and it's just confusing to need to add a space at
803 the end of the program name to prevent this.
804 If you use rules that need the subsystem as the first parameter,
805 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
806 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
810 The udev man page has moved to udev(7) as it does not describe a command
811 anymore. The programs udev, udevstart and udevsend are no longer installed
812 by default and must be copied manually, if they should be installed or
813 included in a package.
815 Fix a bug where "ignore_device" could run earlier collected RUN keys before
816 the ignore rule was applied.
818 More preparation for future sysfs changes. usb_id and scsi_id no longer
819 depend on a magic order of devices in the /devices chain. Specific devices
820 should be requested by their subsytem.
822 This will always find the scsi parent device without depending on a specific
824 dev = sysfs_device_get(devpath);
825 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
827 The "device" link in the current sysfs layout will be automatically
828 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
829 parent in the devpath. If a device is requested by it's symlink, like all
830 class devices in the new sysfs layout will look like, it gets automatically
831 resolved and substituted with the real devpath and not the symlink path.
834 A similar logic must be applied to _all_ sysfs users, including
835 scripts, that search along parent devices in sysfs. The explicit use of
836 the "device" link must be avoided. With the future sysfs layout all
837 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
838 back to the "class" or the "bus". The layout of the parent devices in
839 /devices is not necessarily expected to be stable across kernel releases and
840 searching for parents by their subsystem should make sysfs users tolerant
841 for changed parent chains.
845 Prepare udev to work with the experimental kernel patch, that moves
846 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
848 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
849 moving the class devices to /sys/devices.
851 Thanks again to Marco for help finding a hopefully nice compromise
852 to make %b simpler and working again.
856 Complete removal of libsysfs, replaced by simple helper functions
857 which are much simpler and a bit faster. The udev daemon operatesentirely
858 on event parameters and does not use sysfs for simple rules anymore.
859 Please report any new bugs/problems, that may be caused by this big
860 change. They will be fixed immediately.
862 The enumeration format character '%e' is deprecated and will be
863 removed sometimes from a future udev version. It never worked correctly
864 outside of udevstart, so we can't use it with the new parallel
865 coldplug. A simple enumeration is as useless as the devfs naming
866 scheme, just get rid of both if you still use it.
868 MODALIAS and $modalias is not needed and will be removed from one of
869 the next udev versions, replace it in all rules with ENV{MODALIAS} or
870 the sysfs "modalias" value.
872 Thanks a lot to Marco for all his help on finding and fixing bugs.
876 Let scsi_id request libata drive serial numbers from page 0x80.
878 Renamed etc/udev/persistent.rules to persistent-disk.rules and
879 added /dev/disk/by-name/* for device mapper device names.
881 Removed %e from the man page. It never worked reliably outside
882 of udevstart and udevstart is no longer recommended to use.
886 Symlinks are now exported to the event environment. Hopefully it's no
887 longer needed to run udevinfo from an event process, like it was
888 mentioned on the hotplug list:
889 UDEV [1134776873.702967] add@/block/sdb
892 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
896 Fix a problem if udevsend is used as the hotplug handler and tries to use
897 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
898 and this kind of problems will hopefully go away soon.
902 All built-in logic to work around bad sysfs timing is removed with this
903 version. The need to wait for sysfs files is almost fixed with a kernel
904 version that doesn't work with this udev version anyway. Until we fix
905 the timing of the "bus" link creation, the former integrated logic should
906 be emulated by a rule placed before all other rules:
907 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
909 The option "udev_db" does no longer exist. All udev state will be in
910 /$udev_root/.udev/ now, there is no longer an option to set this
912 If the init script or something else used this value, just depend on
913 this hardcoded path. But remember _all_content_ of this directory is
914 still private to udev and can change at any time.
916 Default location for rule sripts and helper programs is now: /lib/udev/.
917 Everything that is not useful on the commandline should go into this
918 directory. Some of the helpers in the extras folder are installed there
919 now. The rules need to be changed, to find the helpers there.
921 Also /lib/udev/devices is recommended as a directory where packages or
922 the user can place real device nodes, which get copied over to /dev at
923 every boot. This should replace the various solutions with custom config
926 Udevsend does no longer start the udev daemon. This must be done with
927 the init script that prepares /dev on tmpfs and creates the initial nodes,
928 before starting the daemon.
932 Silent a too verbose error logging for the old hotplug.d/ dev.d/
935 The copy of klibc is removed. A systemwide installed version of klibc
936 should be used to build a klibc udev now.
940 NAME="" will not create any nodes, but execute RUN keys. To completely
941 ignore an event the OPTION "ignore_device" should be used.
943 After removal of the reorder queue, events with a TIMEOUT can be executed
944 without any queuing now.
948 Fixed bug in udevd, if inotify is not available. We depend on netlink
949 uevents now, kernels without that event source will not work with that
950 version of udev anymore.
954 The rule parsing happens now in the daemon once at startup, all udev
955 event processes inherit the already parsed rules from the daemon.
956 It is shipped with SUSE10.0 and reduces heavily the system load at
957 startup. The option to save precompiled rules and let the udev process
958 pick the them up is removed, as it's no longer needed.
960 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
961 device. Libsysfs is changed to "translate" the requested link into the
962 real device path, as it would happen with the hotplug event. Otherwise
963 device removal and the udev database will not work.
965 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
968 A few improvements for vol_id, the filesytem probing code.
972 Fix a stupid typo in extras/run_directory for "make install".
974 scsi_id creates the temporary devnode now in /dev for usage with a
975 non-writable /tmp directory.
977 The uevent kernel socket buffer can carry app. 50.000 events now,
978 let's see who can break this again. :)
980 The upcoming kernel will have a new input driver core integration.
981 Some class devices are now symlinks to the real device. libsysfs
982 needs a fix for this to work correctly. Udevstart of older udev
983 versions will _not_ create these devices!
987 Fix a 'install' target in the Makefile, that prevents EXTRAS from
992 A bunch of mostly trivial bugfixes. From now on no node name or
993 symlink name can contain any character than plain whitelisted ascii
994 characters or validated utf8 byte-streams. This is needed for the
995 /dev/disk/by-label/* links, because we import untrusted data and
996 export it to the filesystem.
1000 More bugfixes. If udevd was started from the kernel, we don't
1001 have stdin/stdout/stderr, which broke the forked tools in some
1006 Bugfix. udevstart event ordering was broken for a long time.
1007 The new run_program() uncovered it, because /dev/null was not
1008 available while we try to run external programs.
1009 Now udevstart should create it before we run anything.
1013 Minor bugfixes and some distro rules updates. If you don't have the
1014 persistent disk rules in /dev/disk/by-*/* on your distro, just
1015 grab it from here. :)
1019 We can use socket communication now to pass events from udev to
1021 RUN+="socket:/org/freedesktop/hal/udev_event"
1022 will pass the whole udev event to the HAL daemon without the need
1023 for a forked helper. (See ChangeLog for udevmonitor, as an example)
1027 Mostly bugfixes and see ChangeLog.
1029 The test for the existence of an environment value should be
1031 ENV{KEY}=="*" to ENV{KEY}=="?*"
1032 because "*" will not fail anymore, if the key does not exist or
1037 Bugfixes and a few tweaks described in the ChangeLog.
1041 Mostly a Bugfix release.
1043 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
1044 timing with custom rules.
1048 We changed the internal rule storage format. Our large rule files took
1049 2 MB of RAM, with the change we are down to 99kB.
1051 If the device-node has been created with default name and no symlink or
1052 options are to remenber, it is not longer stored in the udevdb. HAL will
1053 need to be updated to work correctly with that change.
1055 To overrride optimization flags, OPTFLAGS may be used now.
1063 Major changes happened with this release. The goal is to take over the
1064 complete kernel-event handling and provide a more efficient way to dispatch
1065 kernel events. Replacing most of the current shell script logic and the
1066 kernel forked helper with a netlink-daemon and a rule-based event handling.
1068 o udevd listens to netlink events now. The first valid netlink event
1069 will make udevd ignore any message from udevsend that contains a
1070 SEQNUM, to avoid duplicate events. The forked events can be disabled
1072 echo "" > /proc/sys/kernel/hotplug
1073 For full support, the broken input-subsytem needs to be fixed, not to
1074 bypass the driver core.
1076 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
1077 removed from udev itself and must be emulated by calling small
1078 helper binaries provided in the extras folder:
1079 make EXTRAS=extras/run_directory/
1080 will build udev_run_devd and udev_run_hotplugd, which can be called
1081 from a rule if needed:
1082 RUN+="/sbin/udev_run_hotplugd"
1083 The recommended way to handle this is to convert all the calls from
1084 the directories to explicit udev rules and get completely rid of the
1085 multiplexing. (To catch a ttyUSB event, you now no longer need to
1086 fork and exit 300 tty script instances you are not interested in, it
1087 is just one rule that matches exactly the device.)
1089 o udev handles now _all_ events not just events for class and block
1090 devices, this way it is possible to control the complete event
1091 behavior with udev rules. Especially useful for rules like:
1092 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
1094 o As used in the modalias rule, udev supports now textual
1095 substitution placeholder along with the usual format chars. This
1096 needs to be documented, for now it's only visible in udev_rules_parse.c.
1098 o The rule keys support now more operations. This is documented in the
1099 man page. It is possible to add values to list-keys like the SYMLINK
1100 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
1101 Also "final"-assignments are supported by using KEY:="value", which will
1102 prevent changing the key by any later rule.
1104 o kernel 2.6.12 has the "detached_state" attribute removed from
1105 sysfs, which was used to recognize sysfs population. We switched that
1106 to wait for the "bus" link, which is only available in kernels after 2.6.11.
1107 Running this udev version on older kernels may cause a short delay for
1110 o To provide infrastructure for persistent device naming, the id programs:
1111 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
1112 to export the probed data in environment key format:
1113 pim:~ # /sbin/ata_id --export /dev/hda
1114 ID_MODEL=HTS726060M9AT00
1115 ID_SERIAL=MRH401M4G6UM9B
1116 ID_REVISION=MH4OA6BA
1118 The following rules:
1119 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
1120 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
1123 kay@pim:~> tree /dev/disk
1126 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
1127 | `-- IBM-Memory_Key -> ../../sda
1129 | |-- swap -> ../../hda1
1130 | |-- date -> ../../sda1
1131 | `-- home -> ../../hda3
1133 |-- 2E08712B0870F2E7 -> ../../hda3
1134 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
1135 |-- E845-7A89 -> ../../sda1
1136 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
1138 The IMPORT= operation will import these keys in the environment and make
1139 it available for later PROGRAM= and RUN= executed programs. The keys are
1140 also stored in the udevdb and can be queried from there with one of the
1143 o A few binaries are silently added to the repository, which can be used
1144 to replay kernel events from initramfs instead of using coldplug. udevd
1145 can be instructed now to queue-up events while the stored events from
1146 initramfs are filled into the udevd-queue. This code is still under
1147 development and there is no documentation now besides the code itself.
1148 The additional binaries get compiled, but are not installed by default.
1150 o There is also a temporary fix for a performance problem where too many
1151 events happen in parallel and every event needs to parse the rules.
1152 udev can now read precompiled rules stored on disk. This is likely to be
1153 replaced by a more elegant solution in a future udev version.
1157 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
1158 Fix for libsysfs not to expect this file was added.
1162 All rules are applied now, but only the first matching rule with a NAME-key
1163 will be applied. All later rules with NAME-key are completely ignored. This
1164 way system supplied symlinks or permissions gets applied to user-defined
1168 Please check your rules setup, if you may need to add OPTIONS="last_rule"
1169 to some rules, to keep the old behavior.
1171 The rules are read on "remove"-events too. That makes is possible to match
1172 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
1173 instruct udev to ignore an event (OPTIONS="ignore_device").
1174 The new ACTION-key may be used to let a rule act only at a "remove"-event.
1176 The new RUN-key supports rule-based execution of programs after device-node
1177 handling. This is meant as a general replacement for the dev.d/-directories
1178 to give fine grained control over the execution of programs.
1180 The %s{}-sysfs format char replacement values are searched at any of the
1181 devices in the device chain now, not only at the class-device.
1183 We support log priority levels now. The value udev_log in udev.conf is used
1184 to determine what is printed to syslog. This makes it possible to
1185 run a version with compiled-in debug messages in a production environment
1186 which is sometimes needed to find a bug.
1187 It is still possible to supress the inclusion of _any_ syslog usage with
1188 USE_LOG=false to create the smallest possible binaries if needed.
1189 The configured udev_log value can be overridden with the environment variable
1194 Possible use of a system-wide klibc:
1195 make USE_KLIBC=true KLCC=/usr/bin/klcc all
1196 will link against an external klibc and our own version will be ignored.
1200 We support an unlimited count of symlinks now.
1202 If USE_STATIC=true is passed to a glibc build, we link statically and use
1203 a built-in userdb parser to resolve user and group names.
1205 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
1206 we walk up the chain of physical devices to find a match.
1208 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
1209 easy to skip certain attribute matches without composing rules with weird
1210 character class negations like:
1211 KERNEL="[!s][!c][!d]*"
1212 this can now be replaced with:
1214 The current simple '=' is still supported, and should work as it does today,
1215 but existing rules should be converted if possible, to be better readable.
1217 We have new ENV{}== key now, to match against a maximum of 5 environment
1220 udevstart is its own binary again, because we don't need co carry this araound
1221 with every forked event.
~ianmdlvl / elogind.git / blob