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 size of a huge distro rule set to 0.08 MB, compared to the
7 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 need 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 one of these filesytem types match, libvolume_id will not return
20 a probing result if any other filesystem type matches. This is intended
21 to help with conflicting left-over signatures from earlier file system
22 formats. That way, we no longer depend on the probing order for competing
24 In some cases the kernel allows to mount a volume with the old filesystem
25 type, before it has been re-formatted with a different type. This can
26 damage the new filesystem and lead to data loss. Because volume_id can
27 not decide which is the correct signature, the wrong signatures need to
28 be removed manually from the volume, or the volume needs to be reformatted
29 to make filesystem auto-detection and possible auto-mounting working.
34 Fix segfault if compiled without optimization and dbg() does not get
35 compiled out and uses variables which are not available.
39 Bugfixes. (And maybe new bugs. :))
41 The rule matching engine got converted from a rule list to a token
42 array which reduced the in-memory rules representation of a full
43 featured distros with thousends of udev rules from 1.2MB to 0.12 MB.
44 Limits like 5 ENV and ATTR matches, and one single instance for most
45 other keys per rule are gone.
47 The NAME assignment is no longer special cased. If later rules assign
48 a NAME value again, the former value will be overwritten. As usual
49 for most other keys, the NAME value can be protected by doing a final
50 assignment with NAME:="<value>".
52 All udev code now uses libudev, which is also exported. The library
53 is still under development, marked as experimental, and its interface
54 may change as long as the DeviceKit integration is not finished.
56 Many thanks to Alan Jenkins for his continuous help, and finding and
57 optimizing some of the computing expensive parts.
63 Kernel devices and device nodes are connected now by reverse indizes in
64 /sys and /dev. A device number retrieved by a stat() or similar, the
65 kernel device directory can be found by looking up:
66 /sys/dev/{block,char}/<maj>:<min>
67 and the device node of the same device by looking up:
68 /dev/{block,char}/<maj>:<min>
72 Fix recently introduced bug, which caused a compilation without large
73 file support, where vol_id does not recognize raid signatures at the end
76 Firewire disks now create both, by-id/scsi-* and by-id/ieee-* links.
77 Seems some kernel versions prevent the creation of the ieee-* links,
78 so people used the scsi-* link which disappeared now.
80 More libudev work. Almost all udevadm functionality comes from libudev
83 udevadm trigger has a new option --type, which allows to trigger events
84 for "devices", for "subsystems", or "failed" devices. The old option
85 --retry-failed" still works, but is no longer mentioned in the man page.
91 The udevadm info --device-id-of-file= output has changed to use
92 the obvious format. Possible current users should use the --export
93 option which is not affected.
95 The old udev commands symlinks to udevadm are not installed, if
96 these symlinks are used, a warning is printed.
102 Optical drive's media is no longer probed for raid signatures,
103 reading the end of the device causes some devices to malfunction.
104 Also the offset of the last session found is used now to probe
107 The volume_id library got a major version number update to 1,
108 some deprecated functions are removed.
110 A shared library "libudev" gets installed now to provide access
111 to udev device information. DeviceKit, the successor of HAL, will
112 need this library to access the udev database and search sysfs for
114 The library is currently in an experimental state, also the API is
115 expected to change, as long as the DeviceKit integration is not
120 We use ./configure now. See INSTALL for details. Current
123 "/usr" - prefix for man pages, include files
125 "" - the root filesystem, prefix for libs and binaries
129 "lib" - directory name for libraries, not a path name
130 multilib 64bit systems may use "lib64" instead of "lib"
132 compile-in verbose debug messages
134 disable all logging and compile-out all log strings
136 link against SELInux libraries, to set the expected context
139 In the default rules, the group "disk" gets permissions 0660 instead
140 of 0640. One small step closer to unify distro rules. Some day, all
141 distros hopefully end up with the same set of rules.
143 No symlinks to udevadm are installed anymore, if they are still needed,
144 they should be provided by the package.
150 Default udev rules, which are not supposed to be edited by the user, should
151 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
152 the udev package and will be replaced with an update. Udev will pick up rule
154 /lib/udev/rules.d/ - default installed rules
155 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
156 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
157 It does not matter in which directory a rule file lives, all files are sorted
160 To help creating /dev/root, we have now:
161 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
164 In case the current --device-id-of-file is already used, please switch to
165 the --export format version, it saves the output parsing and the old
166 format will be changed to use ':' as a separator, like the format in the
171 Fix cdrom_id to properly recognize blank media.
177 Tape drive id-data is queried from /dev/bsg/* instead of the tape
178 nodes. This avoids rewinding tapes on open().
184 The symlinks udevcontrol and udevtrigger are no longer installed by
187 The scsi_id program does not depend on sysfs anymore. It can speak
188 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
189 data, which should solve some old problems with tape devices, where
190 we better do not open all tape device nodes to identify the device.
196 The cdrom_id program is replaced by an advanced version, which can
197 detect most common device types, and also properties of the inserted
198 media. This is part of moving some basic functionality from HAL into
199 udev (and the kernel).
205 The last WAIT_FOR_SYSFS rule is removed from the default rules.
207 The symlinks to udevadm for the debugging tools: udevmonitor and
208 udevtest are no longer created.
210 The symlinks to the udevadm man page for the old tool names are
213 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
214 should be prefixed with '@' to indicate that the path is not a
225 Udevstart is removed from the tree, it did not get installed for
226 a long time now, and is long replaced by trigger and settle.
232 All udev tools are merged into a single binary called udevadm.
233 The old names of the tools are built-in commands in udevadm now.
234 Symlinks to udevadm, with the names of the old tools, provide
235 the same functionality as the standalone tools. There is also
236 only a single udevadm.8 man page left for all tools.
238 Tools like mkinitramfs should be checked, if they need to include
239 udevadm in the list of files.
249 The etc/udev/rules.d/ directory now contains a default set of basic
250 udev rules. This initial version is the result of a rules file merge
251 of Fedora and openSUSE. For these both distros only a few specific
252 rules are left in their own file, named after the distro. Rules which
253 are optionally installed, because they are only valid for a specific
254 architecture, or rules for subsystems which are not always used are
255 in etc/udev/packages/.
261 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
262 actions by dynamically created rules.
264 SYMLINK=="<value>" matches agains the entries in the list of
265 currently defined symlinks. The links are not created in the
266 filesystem at that point in time, but the values can be matched.
268 RUN{ignore_error}+="<program>" will ignore any exit code from the
269 program and not record as a failed event.
275 Final merge of patches/features from the Ubuntu package.
281 Control characters in filesystem label strings are no longer silenty
282 removed, but hex-encoded, to be able to uniquely identify the device
283 by its symlink in /dev/disk/by-label/.
284 If libvolume_id is used by mount(8), LABEL= will work as expected,
285 if slashes or other characters are used in the label string.
287 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
288 can be specified now. The TEST key accepts an optional mode mask
289 TEST{0100}=="<is executable file>".
291 Scsi_id now supports a mode without expecting scsi-specific sysfs
292 entries to allow the extraction of cciss-device persistent properties.
298 In the future, we may see uuid's which are just simple character
299 strings (see the DDF Raid Specification). For that reason vol_id now
300 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
301 the creation of symlinks, the *_SAFE values ensure, that no control
302 or whitespace characters are used in the filename.
304 Possible users of libvolume_id, please use the volume_id_get_* functions.
305 The public struct will go away in a future release of the library.
311 Removal of useless extras/eventrecorder.sh.
321 The directory multiplexer for dev.d/ and hotplug.d are finally removed
322 from the udev package.
328 Symlinks can have priorities now, the priority is assigned to the device
329 and specified with OPTIONS="link_priority=100". Devices with higher
330 priorities overwrite the symlinks of devices with lower priorities.
331 If the device that currently owns the link, goes away, the symlink
332 will be removed, and recreated, pointing to the next device with the
333 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
334 more reliable, if multiple devices contain the same metadata and overwrite
337 The dasd_id program is removed from the udev tree, and dasdinfo, with the
338 needed rules, are part of the s390-tools now.
340 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
341 we may get the scsi sysfs mess fixed some day, and this will only catch
342 the devices we are looking for.
344 USB serial numbers for storage devices have the target:lun now appended,
345 to make it possibble to distinguish broken multi-lun devices with all
346 the same SCSI identifiers.
348 Note: The extra "run_directory" which searches and executes stuff in
349 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
350 with the next release. Make sure, that you don't use it anymore, or
351 provides your own implementation of that inefficient stuff.
352 We are tired of reports about a "slow udev", because these directories
353 contain stuff, that runs with _every_ event, instead of using rules,
354 that run programs only for the matching events.
364 DRIVER== will match only for devices that actually have a real
365 driver. DRIVERS== must be used, if parent devices should be
366 included in the match.
368 Libvolume_id's "linux_raid" detection needed another fix.
376 Add additional check to volume_id detection of via_raid, cause
377 some company decided to put a matching pattern all over the empty
378 storage area of their music players.
382 Fix path_id for SAS devices.
386 The udev daemon can be started with --debug-trace now, which will
387 execute all events serialized to get a chance to catch a possible
388 action that crashes the box.
390 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
391 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
392 are excluded from the warning. Referencing parent attributes directly
393 may break when something in the kernel driver model changes. Udev will
394 just find the attribute by walking up the parent chain.
396 Udevtrigger now sorts the list of devices depending on the device
397 dependency, so a "usb" device is triggered after the parent "pci"
402 Revert persistent-storage ata-serial '_' '-' replacement.
408 Udevtrigger can now filter the list of devices to be triggered. Matches
409 for subsystems or sysfs attributes can be specified.
411 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
412 zero-sized files to avoid pointing to /sys and confuse broken tools which
413 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
416 The rules and scripts to create udev rules for persistent network
417 devices and optical drives are in the extras/rules_generator directory
418 now. If you use something similar, please consider replacing your own
419 version with this, to share the support effort. The rule_generator
420 installs its own rules into /etc/udev/rules.d.
422 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
423 the rule_generator depends on cdrom_id to be called in an earlier rule.
429 Renaming of some key names (the old names still work):
430 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
431 (The behavior of the key DRIVER will change soon in one of the next
432 releases, to match only the event device, please switch to DRIVERS
433 instead. If DRIVER is used, it will behave like DRIVERS, but an error
435 With the new key names, we have a more consistent and simpler scheme.
436 We can match the properties of the event device only, with: KERNEL,
437 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
438 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
439 longer mentioned in the man page and should be switched in the rule
442 ATTR{file}="value" can be used now, to write to a sysfs file of the
443 event device. Instead of:
444 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
446 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
448 All the PHYSDEV* keys are deprecated and will be removed from a
450 PHYDEVPATH - is the path of a parent device and should not be
452 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
453 matched with SUBSYSTEMS==
454 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
455 Newer kernels will have DRIVER in the environment,
456 for older kernels udev puts in. Class device will
457 no longer carry this property of a parent and
458 DRIVERS== can be used to match such a parent value.
459 Note that ENV{DRIVER} is only available for a few bus devices, where
460 the driver is already bound at device event time. On coldplug, the
461 events for a lot devices are already bound to a driver, and they will have
462 that value set. But on hotplug, at the time the kernel creates the device,
463 it can't know what driver may claim the device after that, therefore
464 in most cases it will be empty.
466 Failed events should now be re-triggered with:
467 udevtrigger --retry-failed.
468 Please switch to this command, so we keep the details of the /dev/.udev/failed/
469 files private to the udev tools. We may need to switch the current symlink
470 target, cause some obviously broken tools try to scan all files in /dev
471 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
472 million times. This takes ages on slow boxes.
474 The udevinfo attribute walk (-a) now works with giving a device node
475 name (-n) instead of a devpath (-p). The query now always works, also when
476 no database file was created by udev.
478 The built-in /etc/passwd /etc/group parser is removed, we always depend on
479 getpwnam() and getgrnam() now. One of the next releases will depend on
480 fnmatch() and may use getopt_long().
484 Bugfixes and small improvements.
488 Fix path_id for recent kernels.
494 Added support for swapping network interface names, by temporarily
495 renaming the device and wait for the target name to become free.
499 The built-in MODALIAS key and substitution is removed.
503 The binary firmware helper is replaced by the usual simple
504 shell script. Udevsend is removed from the tree.
512 Some more keys require the correct use of '==' and '=' depending
513 on the kind of operation beeing an assignment or a match. Rules
514 with invalid operations are skipped and logged to syslog. Please
515 test with udevtest if the parsing of your rules throws errors and
516 fix possibly broken rules.
520 Provide "udevsettle" to wait for all current udev events to finish.
521 It also watches the current kernel netlink queue by comparing the
522 even sequence number to make sure that there are no current pending
523 events that have not already arrived in the daemon.
527 Fix rule to skip persistent rules for removable IDE devices, which
528 also skipped optical IDE drives.
530 All *_id program are installed in /lib/udev/ by default now.
532 No binary is stripped anymore as this should be done in the
533 packaging process and not at build time.
535 libvolume_id is provided as a shared library now and vol_id is
536 linked against it. Also one of the next HAL versions will require
537 this library, and the HAL build process will also require the
538 header file to be installed. The copy of the same code in HAL will
539 be removed to have only a single copy left on the system.
543 Add persistent links for SCSI tapes. The rules file is renamed
544 to 60-persistent-storage.rules.
546 Create persistent path for usb devices. Can be used for all sorts
547 of devices that can't be distinguished by other properties like
548 multiple identical keyboards and mice connected to the same box.
550 Provide "udevtrigger" program to request events on coldplug. The
551 shell script is much too slow with thousends of devices.
555 Fix persistent disk rules to exclude removable IDE drives.
557 Warn if %e, $modalias or MODALIAS is used.
561 Fix queue export, which wasn't correct for subsequent add/remove
562 events for the same device.
566 Fix cramfs detection on big endian.
568 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
573 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
574 attributes were only checked at the parent device that matched the
575 by BUS requested subsystem. Fix it to also look at the device we
576 received the event for.
578 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
583 Fix a bug where NAME="" would prevent RUN from beeing executed.
585 RUN="/bin/program" does not longer automatically add the subsystem
586 as the first parameter. This is from the days of /sbin/hotplug
587 which is dead now and it's just confusing to need to add a space at
588 the end of the program name to prevent this.
589 If you use rules that need the subsystem as the first parameter,
590 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
591 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
595 The udev man page has moved to udev(7) as it does not describe a command
596 anymore. The programs udev, udevstart and udevsend are no longer installed
597 by default and must be copied manually, if they should be installed or
598 included in a package.
600 Fix a bug where "ignore_device" could run earlier collected RUN keys before
601 the ignore rule was applied.
603 More preparation for future sysfs changes. usb_id and scsi_id no longer
604 depend on a magic order of devices in the /devices chain. Specific devices
605 should be requested by their subsytem.
607 This will always find the scsi parent device without depending on a specific
609 dev = sysfs_device_get(devpath);
610 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
612 The "device" link in the current sysfs layout will be automatically
613 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
614 parent in the devpath. If a device is requested by it's symlink, like all
615 class devices in the new sysfs layout will look like, it gets automatically
616 resolved and substituted with the real devpath and not the symlink path.
619 A similar logic must be applied to _all_ sysfs users, including
620 scripts, that search along parent devices in sysfs. The explicit use of
621 the "device" link must be avoided. With the future sysfs layout all
622 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
623 back to the "class" or the "bus". The layout of the parent devices in
624 /devices is not necessarily expected to be stable across kernel releases and
625 searching for parents by their subsystem should make sysfs users tolerant
626 for changed parent chains.
630 Prepare udev to work with the experimental kernel patch, that moves
631 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
633 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
634 moving the class devices to /sys/devices.
636 Thanks again to Marco for help finding a hopefully nice compromise
637 to make %b simpler and working again.
641 Complete removal of libsysfs, replaced by simple helper functions
642 which are much simpler and a bit faster. The udev daemon operatesentirely
643 on event parameters and does not use sysfs for simple rules anymore.
644 Please report any new bugs/problems, that may be caused by this big
645 change. They will be fixed immediately.
647 The enumeration format character '%e' is deprecated and will be
648 removed sometimes from a future udev version. It never worked correctly
649 outside of udevstart, so we can't use it with the new parallel
650 coldplug. A simple enumeration is as useless as the devfs naming
651 scheme, just get rid of both if you still use it.
653 MODALIAS and $modalias is not needed and will be removed from one of
654 the next udev versions, replace it in all rules with ENV{MODALIAS} or
655 the sysfs "modalias" value.
657 Thanks a lot to Marco for all his help on finding and fixing bugs.
661 Let scsi_id request libata drive serial numbers from page 0x80.
663 Renamed etc/udev/persistent.rules to persistent-disk.rules and
664 added /dev/disk/by-name/* for device mapper device names.
666 Removed %e from the man page. It never worked reliably outside
667 of udevstart and udevstart is no longer recommended to use.
671 Symlinks are now exported to the event environment. Hopefully it's no
672 longer needed to run udevinfo from an event process, like it was
673 mentioned on the hotplug list:
674 UDEV [1134776873.702967] add@/block/sdb
677 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
681 Fix a problem if udevsend is used as the hotplug handler and tries to use
682 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
683 and this kind of problems will hopefully go away soon.
687 All built-in logic to work around bad sysfs timing is removed with this
688 version. The need to wait for sysfs files is almost fixed with a kernel
689 version that doesn't work with this udev version anyway. Until we fix
690 the timing of the "bus" link creation, the former integrated logic should
691 be emulated by a rule placed before all other rules:
692 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
694 The option "udev_db" does no longer exist. All udev state will be in
695 /$udev_root/.udev/ now, there is no longer an option to set this
697 If the init script or something else used this value, just depend on
698 this hardcoded path. But remember _all_content_ of this directory is
699 still private to udev and can change at any time.
701 Default location for rule sripts and helper programs is now: /lib/udev/.
702 Everything that is not useful on the commandline should go into this
703 directory. Some of the helpers in the extras folder are installed there
704 now. The rules need to be changed, to find the helpers there.
706 Also /lib/udev/devices is recommended as a directory where packages or
707 the user can place real device nodes, which get copied over to /dev at
708 every boot. This should replace the various solutions with custom config
711 Udevsend does no longer start the udev daemon. This must be done with
712 the init script that prepares /dev on tmpfs and creates the initial nodes,
713 before starting the daemon.
717 Silent a too verbose error logging for the old hotplug.d/ dev.d/
720 The copy of klibc is removed. A systemwide installed version of klibc
721 should be used to build a klibc udev now.
725 NAME="" will not create any nodes, but execute RUN keys. To completely
726 ignore an event the OPTION "ignore_device" should be used.
728 After removal of the reorder queue, events with a TIMEOUT can be executed
729 without any queuing now.
733 Fixed bug in udevd, if inotify is not available. We depend on netlink
734 uevents now, kernels without that event source will not work with that
735 version of udev anymore.
739 The rule parsing happens now in the daemon once at startup, all udev
740 event processes inherit the already parsed rules from the daemon.
741 It is shipped with SUSE10.0 and reduces heavily the system load at
742 startup. The option to save precompiled rules and let the udev process
743 pick the them up is removed, as it's no longer needed.
745 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
746 device. Libsysfs is changed to "translate" the requested link into the
747 real device path, as it would happen with the hotplug event. Otherwise
748 device removal and the udev database will not work.
750 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
753 A few improvements for vol_id, the filesytem probing code.
757 Fix a stupid typo in extras/run_directory for "make install".
759 scsi_id creates the temporary devnode now in /dev for usage with a
760 non-writable /tmp directory.
762 The uevent kernel socket buffer can carry app. 50.000 events now,
763 let's see who can break this again. :)
765 The upcoming kernel will have a new input driver core integration.
766 Some class devices are now symlinks to the real device. libsysfs
767 needs a fix for this to work correctly. Udevstart of older udev
768 versions will _not_ create these devices!
772 Fix a 'install' target in the Makefile, that prevents EXTRAS from
777 A bunch of mostly trivial bugfixes. From now on no node name or
778 symlink name can contain any character than plain whitelisted ascii
779 characters or validated utf8 byte-streams. This is needed for the
780 /dev/disk/by-label/* links, because we import untrusted data and
781 export it to the filesystem.
785 More bugfixes. If udevd was started from the kernel, we don't
786 have stdin/stdout/stderr, which broke the forked tools in some
791 Bugfix. udevstart event ordering was broken for a long time.
792 The new run_program() uncovered it, because /dev/null was not
793 available while we try to run external programs.
794 Now udevstart should create it before we run anything.
798 Minor bugfixes and some distro rules updates. If you don't have the
799 persistent disk rules in /dev/disk/by-*/* on your distro, just
800 grab it from here. :)
804 We can use socket communication now to pass events from udev to
806 RUN+="socket:/org/freedesktop/hal/udev_event"
807 will pass the whole udev event to the HAL daemon without the need
808 for a forked helper. (See ChangeLog for udevmonitor, as an example)
812 Mostly bugfixes and see ChangeLog.
814 The test for the existence of an environment value should be
816 ENV{KEY}=="*" to ENV{KEY}=="?*"
817 because "*" will not fail anymore, if the key does not exist or
822 Bugfixes and a few tweaks described in the ChangeLog.
826 Mostly a Bugfix release.
828 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
829 timing with custom rules.
833 We changed the internal rule storage format. Our large rule files took
834 2 MB of RAM, with the change we are down to 99kB.
836 If the device-node has been created with default name and no symlink or
837 options are to remenber, it is not longer stored in the udevdb. HAL will
838 need to be updated to work correctly with that change.
840 To overrride optimization flags, OPTFLAGS may be used now.
848 Major changes happened with this release. The goal is to take over the
849 complete kernel-event handling and provide a more efficient way to dispatch
850 kernel events. Replacing most of the current shell script logic and the
851 kernel forked helper with a netlink-daemon and a rule-based event handling.
853 o udevd listens to netlink events now. The first valid netlink event
854 will make udevd ignore any message from udevsend that contains a
855 SEQNUM, to avoid duplicate events. The forked events can be disabled
857 echo "" > /proc/sys/kernel/hotplug
858 For full support, the broken input-subsytem needs to be fixed, not to
859 bypass the driver core.
861 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
862 removed from udev itself and must be emulated by calling small
863 helper binaries provided in the extras folder:
864 make EXTRAS=extras/run_directory/
865 will build udev_run_devd and udev_run_hotplugd, which can be called
866 from a rule if needed:
867 RUN+="/sbin/udev_run_hotplugd"
868 The recommended way to handle this is to convert all the calls from
869 the directories to explicit udev rules and get completely rid of the
870 multiplexing. (To catch a ttyUSB event, you now no longer need to
871 fork and exit 300 tty script instances you are not interested in, it
872 is just one rule that matches exactly the device.)
874 o udev handles now _all_ events not just events for class and block
875 devices, this way it is possible to control the complete event
876 behavior with udev rules. Especially useful for rules like:
877 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
879 o As used in the modalias rule, udev supports now textual
880 substitution placeholder along with the usual format chars. This
881 needs to be documented, for now it's only visible in udev_rules_parse.c.
883 o The rule keys support now more operations. This is documented in the
884 man page. It is possible to add values to list-keys like the SYMLINK
885 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
886 Also "final"-assignments are supported by using KEY:="value", which will
887 prevent changing the key by any later rule.
889 o kernel 2.6.12 has the "detached_state" attribute removed from
890 sysfs, which was used to recognize sysfs population. We switched that
891 to wait for the "bus" link, which is only available in kernels after 2.6.11.
892 Running this udev version on older kernels may cause a short delay for
895 o To provide infrastructure for persistent device naming, the id programs:
896 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
897 to export the probed data in environment key format:
898 pim:~ # /sbin/ata_id --export /dev/hda
899 ID_MODEL=HTS726060M9AT00
900 ID_SERIAL=MRH401M4G6UM9B
904 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
905 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
908 kay@pim:~> tree /dev/disk
911 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
912 | `-- IBM-Memory_Key -> ../../sda
914 | |-- swap -> ../../hda1
915 | |-- date -> ../../sda1
916 | `-- home -> ../../hda3
918 |-- 2E08712B0870F2E7 -> ../../hda3
919 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
920 |-- E845-7A89 -> ../../sda1
921 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
923 The IMPORT= operation will import these keys in the environment and make
924 it available for later PROGRAM= and RUN= executed programs. The keys are
925 also stored in the udevdb and can be queried from there with one of the
928 o A few binaries are silently added to the repository, which can be used
929 to replay kernel events from initramfs instead of using coldplug. udevd
930 can be instructed now to queue-up events while the stored events from
931 initramfs are filled into the udevd-queue. This code is still under
932 development and there is no documentation now besides the code itself.
933 The additional binaries get compiled, but are not installed by default.
935 o There is also a temporary fix for a performance problem where too many
936 events happen in parallel and every event needs to parse the rules.
937 udev can now read precompiled rules stored on disk. This is likely to be
938 replaced by a more elegant solution in a future udev version.
942 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
943 Fix for libsysfs not to expect this file was added.
947 All rules are applied now, but only the first matching rule with a NAME-key
948 will be applied. All later rules with NAME-key are completely ignored. This
949 way system supplied symlinks or permissions gets applied to user-defined
953 Please check your rules setup, if you may need to add OPTIONS="last_rule"
954 to some rules, to keep the old behavior.
956 The rules are read on "remove"-events too. That makes is possible to match
957 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
958 instruct udev to ignore an event (OPTIONS="ignore_device").
959 The new ACTION-key may be used to let a rule act only at a "remove"-event.
961 The new RUN-key supports rule-based execution of programs after device-node
962 handling. This is meant as a general replacement for the dev.d/-directories
963 to give fine grained control over the execution of programs.
965 The %s{}-sysfs format char replacement values are searched at any of the
966 devices in the device chain now, not only at the class-device.
968 We support log priority levels now. The value udev_log in udev.conf is used
969 to determine what is printed to syslog. This makes it possible to
970 run a version with compiled-in debug messages in a production environment
971 which is sometimes needed to find a bug.
972 It is still possible to supress the inclusion of _any_ syslog usage with
973 USE_LOG=false to create the smallest possible binaries if needed.
974 The configured udev_log value can be overridden with the environment variable
979 Possible use of a system-wide klibc:
980 make USE_KLIBC=true KLCC=/usr/bin/klcc all
981 will link against an external klibc and our own version will be ignored.
985 We support an unlimited count of symlinks now.
987 If USE_STATIC=true is passed to a glibc build, we link statically and use
988 a built-in userdb parser to resolve user and group names.
990 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
991 we walk up the chain of physical devices to find a match.
993 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
994 easy to skip certain attribute matches without composing rules with weird
995 character class negations like:
996 KERNEL="[!s][!c][!d]*"
997 this can now be replaced with:
999 The current simple '=' is still supported, and should work as it does today,
1000 but existing rules should be converted if possible, to be better readable.
1002 We have new ENV{}== key now, to match against a maximum of 5 environment
1005 udevstart is its own binary again, because we don't need co carry this araound
1006 with every forked event.
~ianmdlvl / elogind.git / blob