4 The strings of the parsed rules, which are kept in memory, no longer
5 contain duplicate entries, or duplicate tails of strings. This reduces
6 the total in-memory size of a huge distro rule set to 0.08 MB, compared
7 to the 1.2MB of udev version 130.
9 The export of DEVTYPE=disk/partition got removed from the default
10 rules. This value is available from the kernel.
11 The pnp shell script modprobe hack is removed from the default rules.
12 ACPI devices have proper modalias support and take care of the same
14 Installations which support old kernels, but install current default
15 udev rules may want to add that to the compat rules file.
17 Libvolume_id now always probes for all known filesystems, and does not
18 stop at the first match. Some filesystems are marked as "exclusive probe",
19 and if any other filesytem type matches at the same time, libvolume_id
20 will by default not return any probing result. This is intended to help
21 with conflicting left-over signatures from earlier file system formats.
22 That way, we no longer depend on the probe-order in case of competing
23 signatures. In some setups the kernel allows to mount a volume with just
24 the old filesystem signature still in place. This may damage the new
25 filesystem and cause data-loss, just by mounting it. Because volume_id
26 can not decide which one the correct signature is, the wrong signatures
27 need to be removed manually from the volume, or the volume needs to be
28 reformatted, to enable filesystem detection and possible auto-mounting.
33 Fix segfault if compiled without optimization and dbg() does not get
34 compiled out and uses variables which are not available.
38 Bugfixes. (And maybe new bugs. :))
40 The rule matching engine got converted from a rule list to a token
41 array which reduced the in-memory rules representation of a full
42 featured distros with thousends of udev rules from 1.2MB to 0.12 MB.
43 Limits like 5 ENV and ATTR matches, and one single instance for most
44 other keys per rule are gone.
46 The NAME assignment is no longer special cased. If later rules assign
47 a NAME value again, the former value will be overwritten. As usual
48 for most other keys, the NAME value can be protected by doing a final
49 assignment with NAME:="<value>".
51 All udev code now uses libudev, which is also exported. The library
52 is still under development, marked as experimental, and its interface
53 may change as long as the DeviceKit integration is not finished.
55 Many thanks to Alan Jenkins for his continuous help, and finding and
56 optimizing some of the computing expensive parts.
62 Kernel devices and device nodes are connected now by reverse indizes in
63 /sys and /dev. A device number retrieved by a stat() or similar, the
64 kernel device directory can be found by looking up:
65 /sys/dev/{block,char}/<maj>:<min>
66 and the device node of the same device by looking up:
67 /dev/{block,char}/<maj>:<min>
71 Fix recently introduced bug, which caused a compilation without large
72 file support, where vol_id does not recognize raid signatures at the end
75 Firewire disks now create both, by-id/scsi-* and by-id/ieee-* links.
76 Seems some kernel versions prevent the creation of the ieee-* links,
77 so people used the scsi-* link which disappeared now.
79 More libudev work. Almost all udevadm functionality comes from libudev
82 udevadm trigger has a new option --type, which allows to trigger events
83 for "devices", for "subsystems", or "failed" devices. The old option
84 --retry-failed" still works, but is no longer mentioned in the man page.
90 The udevadm info --device-id-of-file= output has changed to use
91 the obvious format. Possible current users should use the --export
92 option which is not affected.
94 The old udev commands symlinks to udevadm are not installed, if
95 these symlinks are used, a warning is printed.
101 Optical drive's media is no longer probed for raid signatures,
102 reading the end of the device causes some devices to malfunction.
103 Also the offset of the last session found is used now to probe
106 The volume_id library got a major version number update to 1,
107 some deprecated functions are removed.
109 A shared library "libudev" gets installed now to provide access
110 to udev device information. DeviceKit, the successor of HAL, will
111 need this library to access the udev database and search sysfs for
113 The library is currently in an experimental state, also the API is
114 expected to change, as long as the DeviceKit integration is not
119 We use ./configure now. See INSTALL for details. Current
122 "/usr" - prefix for man pages, include files
124 "" - the root filesystem, prefix for libs and binaries
128 "lib" - directory name for libraries, not a path name
129 multilib 64bit systems may use "lib64" instead of "lib"
131 compile-in verbose debug messages
133 disable all logging and compile-out all log strings
135 link against SELInux libraries, to set the expected context
138 In the default rules, the group "disk" gets permissions 0660 instead
139 of 0640. One small step closer to unify distro rules. Some day, all
140 distros hopefully end up with the same set of rules.
142 No symlinks to udevadm are installed anymore, if they are still needed,
143 they should be provided by the package.
149 Default udev rules, which are not supposed to be edited by the user, should
150 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
151 the udev package and will be replaced with an update. Udev will pick up rule
153 /lib/udev/rules.d/ - default installed rules
154 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
155 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
156 It does not matter in which directory a rule file lives, all files are sorted
159 To help creating /dev/root, we have now:
160 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
163 In case the current --device-id-of-file is already used, please switch to
164 the --export format version, it saves the output parsing and the old
165 format will be changed to use ':' as a separator, like the format in the
170 Fix cdrom_id to properly recognize blank media.
176 Tape drive id-data is queried from /dev/bsg/* instead of the tape
177 nodes. This avoids rewinding tapes on open().
183 The symlinks udevcontrol and udevtrigger are no longer installed by
186 The scsi_id program does not depend on sysfs anymore. It can speak
187 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
188 data, which should solve some old problems with tape devices, where
189 we better do not open all tape device nodes to identify the device.
195 The cdrom_id program is replaced by an advanced version, which can
196 detect most common device types, and also properties of the inserted
197 media. This is part of moving some basic functionality from HAL into
198 udev (and the kernel).
204 The last WAIT_FOR_SYSFS rule is removed from the default rules.
206 The symlinks to udevadm for the debugging tools: udevmonitor and
207 udevtest are no longer created.
209 The symlinks to the udevadm man page for the old tool names are
212 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
213 should be prefixed with '@' to indicate that the path is not a
224 Udevstart is removed from the tree, it did not get installed for
225 a long time now, and is long replaced by trigger and settle.
231 All udev tools are merged into a single binary called udevadm.
232 The old names of the tools are built-in commands in udevadm now.
233 Symlinks to udevadm, with the names of the old tools, provide
234 the same functionality as the standalone tools. There is also
235 only a single udevadm.8 man page left for all tools.
237 Tools like mkinitramfs should be checked, if they need to include
238 udevadm in the list of files.
248 The etc/udev/rules.d/ directory now contains a default set of basic
249 udev rules. This initial version is the result of a rules file merge
250 of Fedora and openSUSE. For these both distros only a few specific
251 rules are left in their own file, named after the distro. Rules which
252 are optionally installed, because they are only valid for a specific
253 architecture, or rules for subsystems which are not always used are
254 in etc/udev/packages/.
260 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
261 actions by dynamically created rules.
263 SYMLINK=="<value>" matches agains the entries in the list of
264 currently defined symlinks. The links are not created in the
265 filesystem at that point in time, but the values can be matched.
267 RUN{ignore_error}+="<program>" will ignore any exit code from the
268 program and not record as a failed event.
274 Final merge of patches/features from the Ubuntu package.
280 Control characters in filesystem label strings are no longer silenty
281 removed, but hex-encoded, to be able to uniquely identify the device
282 by its symlink in /dev/disk/by-label/.
283 If libvolume_id is used by mount(8), LABEL= will work as expected,
284 if slashes or other characters are used in the label string.
286 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
287 can be specified now. The TEST key accepts an optional mode mask
288 TEST{0100}=="<is executable file>".
290 Scsi_id now supports a mode without expecting scsi-specific sysfs
291 entries to allow the extraction of cciss-device persistent properties.
297 In the future, we may see uuid's which are just simple character
298 strings (see the DDF Raid Specification). For that reason vol_id now
299 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
300 the creation of symlinks, the *_SAFE values ensure, that no control
301 or whitespace characters are used in the filename.
303 Possible users of libvolume_id, please use the volume_id_get_* functions.
304 The public struct will go away in a future release of the library.
310 Removal of useless extras/eventrecorder.sh.
320 The directory multiplexer for dev.d/ and hotplug.d are finally removed
321 from the udev package.
327 Symlinks can have priorities now, the priority is assigned to the device
328 and specified with OPTIONS="link_priority=100". Devices with higher
329 priorities overwrite the symlinks of devices with lower priorities.
330 If the device that currently owns the link, goes away, the symlink
331 will be removed, and recreated, pointing to the next device with the
332 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
333 more reliable, if multiple devices contain the same metadata and overwrite
336 The dasd_id program is removed from the udev tree, and dasdinfo, with the
337 needed rules, are part of the s390-tools now.
339 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
340 we may get the scsi sysfs mess fixed some day, and this will only catch
341 the devices we are looking for.
343 USB serial numbers for storage devices have the target:lun now appended,
344 to make it possibble to distinguish broken multi-lun devices with all
345 the same SCSI identifiers.
347 Note: The extra "run_directory" which searches and executes stuff in
348 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
349 with the next release. Make sure, that you don't use it anymore, or
350 provides your own implementation of that inefficient stuff.
351 We are tired of reports about a "slow udev", because these directories
352 contain stuff, that runs with _every_ event, instead of using rules,
353 that run programs only for the matching events.
363 DRIVER== will match only for devices that actually have a real
364 driver. DRIVERS== must be used, if parent devices should be
365 included in the match.
367 Libvolume_id's "linux_raid" detection needed another fix.
375 Add additional check to volume_id detection of via_raid, cause
376 some company decided to put a matching pattern all over the empty
377 storage area of their music players.
381 Fix path_id for SAS devices.
385 The udev daemon can be started with --debug-trace now, which will
386 execute all events serialized to get a chance to catch a possible
387 action that crashes the box.
389 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
390 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
391 are excluded from the warning. Referencing parent attributes directly
392 may break when something in the kernel driver model changes. Udev will
393 just find the attribute by walking up the parent chain.
395 Udevtrigger now sorts the list of devices depending on the device
396 dependency, so a "usb" device is triggered after the parent "pci"
401 Revert persistent-storage ata-serial '_' '-' replacement.
407 Udevtrigger can now filter the list of devices to be triggered. Matches
408 for subsystems or sysfs attributes can be specified.
410 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
411 zero-sized files to avoid pointing to /sys and confuse broken tools which
412 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
415 The rules and scripts to create udev rules for persistent network
416 devices and optical drives are in the extras/rules_generator directory
417 now. If you use something similar, please consider replacing your own
418 version with this, to share the support effort. The rule_generator
419 installs its own rules into /etc/udev/rules.d.
421 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
422 the rule_generator depends on cdrom_id to be called in an earlier rule.
428 Renaming of some key names (the old names still work):
429 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
430 (The behavior of the key DRIVER will change soon in one of the next
431 releases, to match only the event device, please switch to DRIVERS
432 instead. If DRIVER is used, it will behave like DRIVERS, but an error
434 With the new key names, we have a more consistent and simpler scheme.
435 We can match the properties of the event device only, with: KERNEL,
436 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
437 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
438 longer mentioned in the man page and should be switched in the rule
441 ATTR{file}="value" can be used now, to write to a sysfs file of the
442 event device. Instead of:
443 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
445 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
447 All the PHYSDEV* keys are deprecated and will be removed from a
449 PHYDEVPATH - is the path of a parent device and should not be
451 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
452 matched with SUBSYSTEMS==
453 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
454 Newer kernels will have DRIVER in the environment,
455 for older kernels udev puts in. Class device will
456 no longer carry this property of a parent and
457 DRIVERS== can be used to match such a parent value.
458 Note that ENV{DRIVER} is only available for a few bus devices, where
459 the driver is already bound at device event time. On coldplug, the
460 events for a lot devices are already bound to a driver, and they will have
461 that value set. But on hotplug, at the time the kernel creates the device,
462 it can't know what driver may claim the device after that, therefore
463 in most cases it will be empty.
465 Failed events should now be re-triggered with:
466 udevtrigger --retry-failed.
467 Please switch to this command, so we keep the details of the /dev/.udev/failed/
468 files private to the udev tools. We may need to switch the current symlink
469 target, cause some obviously broken tools try to scan all files in /dev
470 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
471 million times. This takes ages on slow boxes.
473 The udevinfo attribute walk (-a) now works with giving a device node
474 name (-n) instead of a devpath (-p). The query now always works, also when
475 no database file was created by udev.
477 The built-in /etc/passwd /etc/group parser is removed, we always depend on
478 getpwnam() and getgrnam() now. One of the next releases will depend on
479 fnmatch() and may use getopt_long().
483 Bugfixes and small improvements.
487 Fix path_id for recent kernels.
493 Added support for swapping network interface names, by temporarily
494 renaming the device and wait for the target name to become free.
498 The built-in MODALIAS key and substitution is removed.
502 The binary firmware helper is replaced by the usual simple
503 shell script. Udevsend is removed from the tree.
511 Some more keys require the correct use of '==' and '=' depending
512 on the kind of operation beeing an assignment or a match. Rules
513 with invalid operations are skipped and logged to syslog. Please
514 test with udevtest if the parsing of your rules throws errors and
515 fix possibly broken rules.
519 Provide "udevsettle" to wait for all current udev events to finish.
520 It also watches the current kernel netlink queue by comparing the
521 even sequence number to make sure that there are no current pending
522 events that have not already arrived in the daemon.
526 Fix rule to skip persistent rules for removable IDE devices, which
527 also skipped optical IDE drives.
529 All *_id program are installed in /lib/udev/ by default now.
531 No binary is stripped anymore as this should be done in the
532 packaging process and not at build time.
534 libvolume_id is provided as a shared library now and vol_id is
535 linked against it. Also one of the next HAL versions will require
536 this library, and the HAL build process will also require the
537 header file to be installed. The copy of the same code in HAL will
538 be removed to have only a single copy left on the system.
542 Add persistent links for SCSI tapes. The rules file is renamed
543 to 60-persistent-storage.rules.
545 Create persistent path for usb devices. Can be used for all sorts
546 of devices that can't be distinguished by other properties like
547 multiple identical keyboards and mice connected to the same box.
549 Provide "udevtrigger" program to request events on coldplug. The
550 shell script is much too slow with thousends of devices.
554 Fix persistent disk rules to exclude removable IDE drives.
556 Warn if %e, $modalias or MODALIAS is used.
560 Fix queue export, which wasn't correct for subsequent add/remove
561 events for the same device.
565 Fix cramfs detection on big endian.
567 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
572 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
573 attributes were only checked at the parent device that matched the
574 by BUS requested subsystem. Fix it to also look at the device we
575 received the event for.
577 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
582 Fix a bug where NAME="" would prevent RUN from beeing executed.
584 RUN="/bin/program" does not longer automatically add the subsystem
585 as the first parameter. This is from the days of /sbin/hotplug
586 which is dead now and it's just confusing to need to add a space at
587 the end of the program name to prevent this.
588 If you use rules that need the subsystem as the first parameter,
589 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
590 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
594 The udev man page has moved to udev(7) as it does not describe a command
595 anymore. The programs udev, udevstart and udevsend are no longer installed
596 by default and must be copied manually, if they should be installed or
597 included in a package.
599 Fix a bug where "ignore_device" could run earlier collected RUN keys before
600 the ignore rule was applied.
602 More preparation for future sysfs changes. usb_id and scsi_id no longer
603 depend on a magic order of devices in the /devices chain. Specific devices
604 should be requested by their subsytem.
606 This will always find the scsi parent device without depending on a specific
608 dev = sysfs_device_get(devpath);
609 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
611 The "device" link in the current sysfs layout will be automatically
612 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
613 parent in the devpath. If a device is requested by it's symlink, like all
614 class devices in the new sysfs layout will look like, it gets automatically
615 resolved and substituted with the real devpath and not the symlink path.
618 A similar logic must be applied to _all_ sysfs users, including
619 scripts, that search along parent devices in sysfs. The explicit use of
620 the "device" link must be avoided. With the future sysfs layout all
621 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
622 back to the "class" or the "bus". The layout of the parent devices in
623 /devices is not necessarily expected to be stable across kernel releases and
624 searching for parents by their subsystem should make sysfs users tolerant
625 for changed parent chains.
629 Prepare udev to work with the experimental kernel patch, that moves
630 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
632 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
633 moving the class devices to /sys/devices.
635 Thanks again to Marco for help finding a hopefully nice compromise
636 to make %b simpler and working again.
640 Complete removal of libsysfs, replaced by simple helper functions
641 which are much simpler and a bit faster. The udev daemon operatesentirely
642 on event parameters and does not use sysfs for simple rules anymore.
643 Please report any new bugs/problems, that may be caused by this big
644 change. They will be fixed immediately.
646 The enumeration format character '%e' is deprecated and will be
647 removed sometimes from a future udev version. It never worked correctly
648 outside of udevstart, so we can't use it with the new parallel
649 coldplug. A simple enumeration is as useless as the devfs naming
650 scheme, just get rid of both if you still use it.
652 MODALIAS and $modalias is not needed and will be removed from one of
653 the next udev versions, replace it in all rules with ENV{MODALIAS} or
654 the sysfs "modalias" value.
656 Thanks a lot to Marco for all his help on finding and fixing bugs.
660 Let scsi_id request libata drive serial numbers from page 0x80.
662 Renamed etc/udev/persistent.rules to persistent-disk.rules and
663 added /dev/disk/by-name/* for device mapper device names.
665 Removed %e from the man page. It never worked reliably outside
666 of udevstart and udevstart is no longer recommended to use.
670 Symlinks are now exported to the event environment. Hopefully it's no
671 longer needed to run udevinfo from an event process, like it was
672 mentioned on the hotplug list:
673 UDEV [1134776873.702967] add@/block/sdb
676 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
680 Fix a problem if udevsend is used as the hotplug handler and tries to use
681 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
682 and this kind of problems will hopefully go away soon.
686 All built-in logic to work around bad sysfs timing is removed with this
687 version. The need to wait for sysfs files is almost fixed with a kernel
688 version that doesn't work with this udev version anyway. Until we fix
689 the timing of the "bus" link creation, the former integrated logic should
690 be emulated by a rule placed before all other rules:
691 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
693 The option "udev_db" does no longer exist. All udev state will be in
694 /$udev_root/.udev/ now, there is no longer an option to set this
696 If the init script or something else used this value, just depend on
697 this hardcoded path. But remember _all_content_ of this directory is
698 still private to udev and can change at any time.
700 Default location for rule sripts and helper programs is now: /lib/udev/.
701 Everything that is not useful on the commandline should go into this
702 directory. Some of the helpers in the extras folder are installed there
703 now. The rules need to be changed, to find the helpers there.
705 Also /lib/udev/devices is recommended as a directory where packages or
706 the user can place real device nodes, which get copied over to /dev at
707 every boot. This should replace the various solutions with custom config
710 Udevsend does no longer start the udev daemon. This must be done with
711 the init script that prepares /dev on tmpfs and creates the initial nodes,
712 before starting the daemon.
716 Silent a too verbose error logging for the old hotplug.d/ dev.d/
719 The copy of klibc is removed. A systemwide installed version of klibc
720 should be used to build a klibc udev now.
724 NAME="" will not create any nodes, but execute RUN keys. To completely
725 ignore an event the OPTION "ignore_device" should be used.
727 After removal of the reorder queue, events with a TIMEOUT can be executed
728 without any queuing now.
732 Fixed bug in udevd, if inotify is not available. We depend on netlink
733 uevents now, kernels without that event source will not work with that
734 version of udev anymore.
738 The rule parsing happens now in the daemon once at startup, all udev
739 event processes inherit the already parsed rules from the daemon.
740 It is shipped with SUSE10.0 and reduces heavily the system load at
741 startup. The option to save precompiled rules and let the udev process
742 pick the them up is removed, as it's no longer needed.
744 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
745 device. Libsysfs is changed to "translate" the requested link into the
746 real device path, as it would happen with the hotplug event. Otherwise
747 device removal and the udev database will not work.
749 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
752 A few improvements for vol_id, the filesytem probing code.
756 Fix a stupid typo in extras/run_directory for "make install".
758 scsi_id creates the temporary devnode now in /dev for usage with a
759 non-writable /tmp directory.
761 The uevent kernel socket buffer can carry app. 50.000 events now,
762 let's see who can break this again. :)
764 The upcoming kernel will have a new input driver core integration.
765 Some class devices are now symlinks to the real device. libsysfs
766 needs a fix for this to work correctly. Udevstart of older udev
767 versions will _not_ create these devices!
771 Fix a 'install' target in the Makefile, that prevents EXTRAS from
776 A bunch of mostly trivial bugfixes. From now on no node name or
777 symlink name can contain any character than plain whitelisted ascii
778 characters or validated utf8 byte-streams. This is needed for the
779 /dev/disk/by-label/* links, because we import untrusted data and
780 export it to the filesystem.
784 More bugfixes. If udevd was started from the kernel, we don't
785 have stdin/stdout/stderr, which broke the forked tools in some
790 Bugfix. udevstart event ordering was broken for a long time.
791 The new run_program() uncovered it, because /dev/null was not
792 available while we try to run external programs.
793 Now udevstart should create it before we run anything.
797 Minor bugfixes and some distro rules updates. If you don't have the
798 persistent disk rules in /dev/disk/by-*/* on your distro, just
799 grab it from here. :)
803 We can use socket communication now to pass events from udev to
805 RUN+="socket:/org/freedesktop/hal/udev_event"
806 will pass the whole udev event to the HAL daemon without the need
807 for a forked helper. (See ChangeLog for udevmonitor, as an example)
811 Mostly bugfixes and see ChangeLog.
813 The test for the existence of an environment value should be
815 ENV{KEY}=="*" to ENV{KEY}=="?*"
816 because "*" will not fail anymore, if the key does not exist or
821 Bugfixes and a few tweaks described in the ChangeLog.
825 Mostly a Bugfix release.
827 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
828 timing with custom rules.
832 We changed the internal rule storage format. Our large rule files took
833 2 MB of RAM, with the change we are down to 99kB.
835 If the device-node has been created with default name and no symlink or
836 options are to remenber, it is not longer stored in the udevdb. HAL will
837 need to be updated to work correctly with that change.
839 To overrride optimization flags, OPTFLAGS may be used now.
847 Major changes happened with this release. The goal is to take over the
848 complete kernel-event handling and provide a more efficient way to dispatch
849 kernel events. Replacing most of the current shell script logic and the
850 kernel forked helper with a netlink-daemon and a rule-based event handling.
852 o udevd listens to netlink events now. The first valid netlink event
853 will make udevd ignore any message from udevsend that contains a
854 SEQNUM, to avoid duplicate events. The forked events can be disabled
856 echo "" > /proc/sys/kernel/hotplug
857 For full support, the broken input-subsytem needs to be fixed, not to
858 bypass the driver core.
860 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
861 removed from udev itself and must be emulated by calling small
862 helper binaries provided in the extras folder:
863 make EXTRAS=extras/run_directory/
864 will build udev_run_devd and udev_run_hotplugd, which can be called
865 from a rule if needed:
866 RUN+="/sbin/udev_run_hotplugd"
867 The recommended way to handle this is to convert all the calls from
868 the directories to explicit udev rules and get completely rid of the
869 multiplexing. (To catch a ttyUSB event, you now no longer need to
870 fork and exit 300 tty script instances you are not interested in, it
871 is just one rule that matches exactly the device.)
873 o udev handles now _all_ events not just events for class and block
874 devices, this way it is possible to control the complete event
875 behavior with udev rules. Especially useful for rules like:
876 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
878 o As used in the modalias rule, udev supports now textual
879 substitution placeholder along with the usual format chars. This
880 needs to be documented, for now it's only visible in udev_rules_parse.c.
882 o The rule keys support now more operations. This is documented in the
883 man page. It is possible to add values to list-keys like the SYMLINK
884 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
885 Also "final"-assignments are supported by using KEY:="value", which will
886 prevent changing the key by any later rule.
888 o kernel 2.6.12 has the "detached_state" attribute removed from
889 sysfs, which was used to recognize sysfs population. We switched that
890 to wait for the "bus" link, which is only available in kernels after 2.6.11.
891 Running this udev version on older kernels may cause a short delay for
894 o To provide infrastructure for persistent device naming, the id programs:
895 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
896 to export the probed data in environment key format:
897 pim:~ # /sbin/ata_id --export /dev/hda
898 ID_MODEL=HTS726060M9AT00
899 ID_SERIAL=MRH401M4G6UM9B
903 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
904 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
907 kay@pim:~> tree /dev/disk
910 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
911 | `-- IBM-Memory_Key -> ../../sda
913 | |-- swap -> ../../hda1
914 | |-- date -> ../../sda1
915 | `-- home -> ../../hda3
917 |-- 2E08712B0870F2E7 -> ../../hda3
918 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
919 |-- E845-7A89 -> ../../sda1
920 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
922 The IMPORT= operation will import these keys in the environment and make
923 it available for later PROGRAM= and RUN= executed programs. The keys are
924 also stored in the udevdb and can be queried from there with one of the
927 o A few binaries are silently added to the repository, which can be used
928 to replay kernel events from initramfs instead of using coldplug. udevd
929 can be instructed now to queue-up events while the stored events from
930 initramfs are filled into the udevd-queue. This code is still under
931 development and there is no documentation now besides the code itself.
932 The additional binaries get compiled, but are not installed by default.
934 o There is also a temporary fix for a performance problem where too many
935 events happen in parallel and every event needs to parse the rules.
936 udev can now read precompiled rules stored on disk. This is likely to be
937 replaced by a more elegant solution in a future udev version.
941 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
942 Fix for libsysfs not to expect this file was added.
946 All rules are applied now, but only the first matching rule with a NAME-key
947 will be applied. All later rules with NAME-key are completely ignored. This
948 way system supplied symlinks or permissions gets applied to user-defined
952 Please check your rules setup, if you may need to add OPTIONS="last_rule"
953 to some rules, to keep the old behavior.
955 The rules are read on "remove"-events too. That makes is possible to match
956 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
957 instruct udev to ignore an event (OPTIONS="ignore_device").
958 The new ACTION-key may be used to let a rule act only at a "remove"-event.
960 The new RUN-key supports rule-based execution of programs after device-node
961 handling. This is meant as a general replacement for the dev.d/-directories
962 to give fine grained control over the execution of programs.
964 The %s{}-sysfs format char replacement values are searched at any of the
965 devices in the device chain now, not only at the class-device.
967 We support log priority levels now. The value udev_log in udev.conf is used
968 to determine what is printed to syslog. This makes it possible to
969 run a version with compiled-in debug messages in a production environment
970 which is sometimes needed to find a bug.
971 It is still possible to supress the inclusion of _any_ syslog usage with
972 USE_LOG=false to create the smallest possible binaries if needed.
973 The configured udev_log value can be overridden with the environment variable
978 Possible use of a system-wide klibc:
979 make USE_KLIBC=true KLCC=/usr/bin/klcc all
980 will link against an external klibc and our own version will be ignored.
984 We support an unlimited count of symlinks now.
986 If USE_STATIC=true is passed to a glibc build, we link statically and use
987 a built-in userdb parser to resolve user and group names.
989 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
990 we walk up the chain of physical devices to find a match.
992 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
993 easy to skip certain attribute matches without composing rules with weird
994 character class negations like:
995 KERNEL="[!s][!c][!d]*"
996 this can now be replaced with:
998 The current simple '=' is still supported, and should work as it does today,
999 but existing rules should be converted if possible, to be better readable.
1001 We have new ENV{}== key now, to match against a maximum of 5 environment
1004 udevstart is its own binary again, because we don't need co carry this araound
1005 with every forked event.
~ianmdlvl / elogind.git / blob