6 Bugfix for kernels using SYSFS_DEPRECATED* option and finding parent
7 block devices in some cases. No common distro uses this option anymore,
8 and we do not get enough testing for this and recent udev versions. If
9 this option is not needed to run some old distro with a new kernel,
10 it should be disabled in the kernel config.
12 Bugfix for the $links substitution variable, which may crash if no links
13 are created. This should not happen in usual setups because we always
14 create /dev/{block,char}/ links.
16 The strings of the parsed rules, which are kept in memory, no longer
17 contain duplicate entries, or duplicate tails of strings. This, and the
18 new rules parsing/matching code reduces the total in-memory size of
19 a huge distro rule sets to 0.08 MB, compared to the 1.2MB of udev
22 The export of DEVTYPE=disk/partition got removed from the default
23 rules. This value is available from the kernel. The pnp shell script
24 modprobe hack is removed from the default rules. ACPI devices have _proper_
25 modalias support and take care of the same functionality.
26 Installations which support old kernels, but install current default
27 udev rules may want to add that to the compat rules file.
29 Libvolume_id now always probes for all known filesystems, and does not
30 stop at the first match. Some filesystems are marked as "exclusive probe",
31 and if any other filesytem type matches at the same time, libvolume_id
32 will, by default, not return any probing result. This is intended to prevent
33 mis-detection with conflicting left-over signatures found from earlier
34 file system formats. That way, we no longer depend on the probe-order
35 in case of multiple competing signatures. In some setups the kernel allows
36 to mount a volume with just the old filesystem signature still in place.
37 This may damage the new filesystem and cause data-loss, just by mounting
38 it. Because volume_id can not decide which one the correct signature is,
39 the wrong signatures need to be removed manually from the volume, or the
40 volume needs to be reformatted, to enable filesystem detection and possible
45 Fix segfault if compiled without optimization and dbg() does not get
46 compiled out and uses variables which are not available.
50 Bugfixes. (And maybe new bugs. :))
52 The rule matching engine got converted from a rule list to a token
53 array which reduced the in-memory rules representation of a full
54 featured distros with thousends of udev rules from 1.2MB to 0.12 MB.
55 Limits like 5 ENV and ATTR matches, and one single instance for most
56 other keys per rule are gone.
58 The NAME assignment is no longer special cased. If later rules assign
59 a NAME value again, the former value will be overwritten. As usual
60 for most other keys, the NAME value can be protected by doing a final
61 assignment with NAME:="<value>".
63 All udev code now uses libudev, which is also exported. The library
64 is still under development, marked as experimental, and its interface
65 may change as long as the DeviceKit integration is not finished.
67 Many thanks to Alan Jenkins for his continuous help, and finding and
68 optimizing some of the computing expensive parts.
74 Kernel devices and device nodes are connected now by reverse indizes in
75 /sys and /dev. A device number retrieved by a stat() or similar, the
76 kernel device directory can be found by looking up:
77 /sys/dev/{block,char}/<maj>:<min>
78 and the device node of the same device by looking up:
79 /dev/{block,char}/<maj>:<min>
83 Fix recently introduced bug, which caused a compilation without large
84 file support, where vol_id does not recognize raid signatures at the end
87 Firewire disks now create both, by-id/scsi-* and by-id/ieee-* links.
88 Seems some kernel versions prevent the creation of the ieee-* links,
89 so people used the scsi-* link which disappeared now.
91 More libudev work. Almost all udevadm functionality comes from libudev
94 udevadm trigger has a new option --type, which allows to trigger events
95 for "devices", for "subsystems", or "failed" devices. The old option
96 --retry-failed" still works, but is no longer mentioned in the man page.
102 The udevadm info --device-id-of-file= output has changed to use
103 the obvious format. Possible current users should use the --export
104 option which is not affected.
106 The old udev commands symlinks to udevadm are not installed, if
107 these symlinks are used, a warning is printed.
113 Optical drive's media is no longer probed for raid signatures,
114 reading the end of the device causes some devices to malfunction.
115 Also the offset of the last session found is used now to probe
118 The volume_id library got a major version number update to 1,
119 some deprecated functions are removed.
121 A shared library "libudev" gets installed now to provide access
122 to udev device information. DeviceKit, the successor of HAL, will
123 need this library to access the udev database and search sysfs for
125 The library is currently in an experimental state, also the API is
126 expected to change, as long as the DeviceKit integration is not
131 We use ./configure now. See INSTALL for details. Current
134 "/usr" - prefix for man pages, include files
136 "" - the root filesystem, prefix for libs and binaries
140 "lib" - directory name for libraries, not a path name
141 multilib 64bit systems may use "lib64" instead of "lib"
143 compile-in verbose debug messages
145 disable all logging and compile-out all log strings
147 link against SELInux libraries, to set the expected context
150 In the default rules, the group "disk" gets permissions 0660 instead
151 of 0640. One small step closer to unify distro rules. Some day, all
152 distros hopefully end up with the same set of rules.
154 No symlinks to udevadm are installed anymore, if they are still needed,
155 they should be provided by the package.
161 Default udev rules, which are not supposed to be edited by the user, should
162 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
163 the udev package and will be replaced with an update. Udev will pick up rule
165 /lib/udev/rules.d/ - default installed rules
166 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
167 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
168 It does not matter in which directory a rule file lives, all files are sorted
171 To help creating /dev/root, we have now:
172 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
175 In case the current --device-id-of-file is already used, please switch to
176 the --export format version, it saves the output parsing and the old
177 format will be changed to use ':' as a separator, like the format in the
182 Fix cdrom_id to properly recognize blank media.
188 Tape drive id-data is queried from /dev/bsg/* instead of the tape
189 nodes. This avoids rewinding tapes on open().
195 The symlinks udevcontrol and udevtrigger are no longer installed by
198 The scsi_id program does not depend on sysfs anymore. It can speak
199 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
200 data, which should solve some old problems with tape devices, where
201 we better do not open all tape device nodes to identify the device.
207 The cdrom_id program is replaced by an advanced version, which can
208 detect most common device types, and also properties of the inserted
209 media. This is part of moving some basic functionality from HAL into
210 udev (and the kernel).
216 The last WAIT_FOR_SYSFS rule is removed from the default rules.
218 The symlinks to udevadm for the debugging tools: udevmonitor and
219 udevtest are no longer created.
221 The symlinks to the udevadm man page for the old tool names are
224 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
225 should be prefixed with '@' to indicate that the path is not a
236 Udevstart is removed from the tree, it did not get installed for
237 a long time now, and is long replaced by trigger and settle.
243 All udev tools are merged into a single binary called udevadm.
244 The old names of the tools are built-in commands in udevadm now.
245 Symlinks to udevadm, with the names of the old tools, provide
246 the same functionality as the standalone tools. There is also
247 only a single udevadm.8 man page left for all tools.
249 Tools like mkinitramfs should be checked, if they need to include
250 udevadm in the list of files.
260 The etc/udev/rules.d/ directory now contains a default set of basic
261 udev rules. This initial version is the result of a rules file merge
262 of Fedora and openSUSE. For these both distros only a few specific
263 rules are left in their own file, named after the distro. Rules which
264 are optionally installed, because they are only valid for a specific
265 architecture, or rules for subsystems which are not always used are
266 in etc/udev/packages/.
272 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
273 actions by dynamically created rules.
275 SYMLINK=="<value>" matches agains the entries in the list of
276 currently defined symlinks. The links are not created in the
277 filesystem at that point in time, but the values can be matched.
279 RUN{ignore_error}+="<program>" will ignore any exit code from the
280 program and not record as a failed event.
286 Final merge of patches/features from the Ubuntu package.
292 Control characters in filesystem label strings are no longer silenty
293 removed, but hex-encoded, to be able to uniquely identify the device
294 by its symlink in /dev/disk/by-label/.
295 If libvolume_id is used by mount(8), LABEL= will work as expected,
296 if slashes or other characters are used in the label string.
298 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
299 can be specified now. The TEST key accepts an optional mode mask
300 TEST{0100}=="<is executable file>".
302 Scsi_id now supports a mode without expecting scsi-specific sysfs
303 entries to allow the extraction of cciss-device persistent properties.
309 In the future, we may see uuid's which are just simple character
310 strings (see the DDF Raid Specification). For that reason vol_id now
311 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
312 the creation of symlinks, the *_SAFE values ensure, that no control
313 or whitespace characters are used in the filename.
315 Possible users of libvolume_id, please use the volume_id_get_* functions.
316 The public struct will go away in a future release of the library.
322 Removal of useless extras/eventrecorder.sh.
332 The directory multiplexer for dev.d/ and hotplug.d are finally removed
333 from the udev package.
339 Symlinks can have priorities now, the priority is assigned to the device
340 and specified with OPTIONS="link_priority=100". Devices with higher
341 priorities overwrite the symlinks of devices with lower priorities.
342 If the device that currently owns the link, goes away, the symlink
343 will be removed, and recreated, pointing to the next device with the
344 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
345 more reliable, if multiple devices contain the same metadata and overwrite
348 The dasd_id program is removed from the udev tree, and dasdinfo, with the
349 needed rules, are part of the s390-tools now.
351 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
352 we may get the scsi sysfs mess fixed some day, and this will only catch
353 the devices we are looking for.
355 USB serial numbers for storage devices have the target:lun now appended,
356 to make it possibble to distinguish broken multi-lun devices with all
357 the same SCSI identifiers.
359 Note: The extra "run_directory" which searches and executes stuff in
360 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
361 with the next release. Make sure, that you don't use it anymore, or
362 provides your own implementation of that inefficient stuff.
363 We are tired of reports about a "slow udev", because these directories
364 contain stuff, that runs with _every_ event, instead of using rules,
365 that run programs only for the matching events.
375 DRIVER== will match only for devices that actually have a real
376 driver. DRIVERS== must be used, if parent devices should be
377 included in the match.
379 Libvolume_id's "linux_raid" detection needed another fix.
387 Add additional check to volume_id detection of via_raid, cause
388 some company decided to put a matching pattern all over the empty
389 storage area of their music players.
393 Fix path_id for SAS devices.
397 The udev daemon can be started with --debug-trace now, which will
398 execute all events serialized to get a chance to catch a possible
399 action that crashes the box.
401 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
402 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
403 are excluded from the warning. Referencing parent attributes directly
404 may break when something in the kernel driver model changes. Udev will
405 just find the attribute by walking up the parent chain.
407 Udevtrigger now sorts the list of devices depending on the device
408 dependency, so a "usb" device is triggered after the parent "pci"
413 Revert persistent-storage ata-serial '_' '-' replacement.
419 Udevtrigger can now filter the list of devices to be triggered. Matches
420 for subsystems or sysfs attributes can be specified.
422 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
423 zero-sized files to avoid pointing to /sys and confuse broken tools which
424 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
427 The rules and scripts to create udev rules for persistent network
428 devices and optical drives are in the extras/rules_generator directory
429 now. If you use something similar, please consider replacing your own
430 version with this, to share the support effort. The rule_generator
431 installs its own rules into /etc/udev/rules.d.
433 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
434 the rule_generator depends on cdrom_id to be called in an earlier rule.
440 Renaming of some key names (the old names still work):
441 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
442 (The behavior of the key DRIVER will change soon in one of the next
443 releases, to match only the event device, please switch to DRIVERS
444 instead. If DRIVER is used, it will behave like DRIVERS, but an error
446 With the new key names, we have a more consistent and simpler scheme.
447 We can match the properties of the event device only, with: KERNEL,
448 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
449 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
450 longer mentioned in the man page and should be switched in the rule
453 ATTR{file}="value" can be used now, to write to a sysfs file of the
454 event device. Instead of:
455 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
457 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
459 All the PHYSDEV* keys are deprecated and will be removed from a
461 PHYDEVPATH - is the path of a parent device and should not be
463 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
464 matched with SUBSYSTEMS==
465 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
466 Newer kernels will have DRIVER in the environment,
467 for older kernels udev puts in. Class device will
468 no longer carry this property of a parent and
469 DRIVERS== can be used to match such a parent value.
470 Note that ENV{DRIVER} is only available for a few bus devices, where
471 the driver is already bound at device event time. On coldplug, the
472 events for a lot devices are already bound to a driver, and they will have
473 that value set. But on hotplug, at the time the kernel creates the device,
474 it can't know what driver may claim the device after that, therefore
475 in most cases it will be empty.
477 Failed events should now be re-triggered with:
478 udevtrigger --retry-failed.
479 Please switch to this command, so we keep the details of the /dev/.udev/failed/
480 files private to the udev tools. We may need to switch the current symlink
481 target, cause some obviously broken tools try to scan all files in /dev
482 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
483 million times. This takes ages on slow boxes.
485 The udevinfo attribute walk (-a) now works with giving a device node
486 name (-n) instead of a devpath (-p). The query now always works, also when
487 no database file was created by udev.
489 The built-in /etc/passwd /etc/group parser is removed, we always depend on
490 getpwnam() and getgrnam() now. One of the next releases will depend on
491 fnmatch() and may use getopt_long().
495 Bugfixes and small improvements.
499 Fix path_id for recent kernels.
505 Added support for swapping network interface names, by temporarily
506 renaming the device and wait for the target name to become free.
510 The built-in MODALIAS key and substitution is removed.
514 The binary firmware helper is replaced by the usual simple
515 shell script. Udevsend is removed from the tree.
523 Some more keys require the correct use of '==' and '=' depending
524 on the kind of operation beeing an assignment or a match. Rules
525 with invalid operations are skipped and logged to syslog. Please
526 test with udevtest if the parsing of your rules throws errors and
527 fix possibly broken rules.
531 Provide "udevsettle" to wait for all current udev events to finish.
532 It also watches the current kernel netlink queue by comparing the
533 even sequence number to make sure that there are no current pending
534 events that have not already arrived in the daemon.
538 Fix rule to skip persistent rules for removable IDE devices, which
539 also skipped optical IDE drives.
541 All *_id program are installed in /lib/udev/ by default now.
543 No binary is stripped anymore as this should be done in the
544 packaging process and not at build time.
546 libvolume_id is provided as a shared library now and vol_id is
547 linked against it. Also one of the next HAL versions will require
548 this library, and the HAL build process will also require the
549 header file to be installed. The copy of the same code in HAL will
550 be removed to have only a single copy left on the system.
554 Add persistent links for SCSI tapes. The rules file is renamed
555 to 60-persistent-storage.rules.
557 Create persistent path for usb devices. Can be used for all sorts
558 of devices that can't be distinguished by other properties like
559 multiple identical keyboards and mice connected to the same box.
561 Provide "udevtrigger" program to request events on coldplug. The
562 shell script is much too slow with thousends of devices.
566 Fix persistent disk rules to exclude removable IDE drives.
568 Warn if %e, $modalias or MODALIAS is used.
572 Fix queue export, which wasn't correct for subsequent add/remove
573 events for the same device.
577 Fix cramfs detection on big endian.
579 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
584 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
585 attributes were only checked at the parent device that matched the
586 by BUS requested subsystem. Fix it to also look at the device we
587 received the event for.
589 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
594 Fix a bug where NAME="" would prevent RUN from beeing executed.
596 RUN="/bin/program" does not longer automatically add the subsystem
597 as the first parameter. This is from the days of /sbin/hotplug
598 which is dead now and it's just confusing to need to add a space at
599 the end of the program name to prevent this.
600 If you use rules that need the subsystem as the first parameter,
601 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
602 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
606 The udev man page has moved to udev(7) as it does not describe a command
607 anymore. The programs udev, udevstart and udevsend are no longer installed
608 by default and must be copied manually, if they should be installed or
609 included in a package.
611 Fix a bug where "ignore_device" could run earlier collected RUN keys before
612 the ignore rule was applied.
614 More preparation for future sysfs changes. usb_id and scsi_id no longer
615 depend on a magic order of devices in the /devices chain. Specific devices
616 should be requested by their subsytem.
618 This will always find the scsi parent device without depending on a specific
620 dev = sysfs_device_get(devpath);
621 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
623 The "device" link in the current sysfs layout will be automatically
624 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
625 parent in the devpath. If a device is requested by it's symlink, like all
626 class devices in the new sysfs layout will look like, it gets automatically
627 resolved and substituted with the real devpath and not the symlink path.
630 A similar logic must be applied to _all_ sysfs users, including
631 scripts, that search along parent devices in sysfs. The explicit use of
632 the "device" link must be avoided. With the future sysfs layout all
633 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
634 back to the "class" or the "bus". The layout of the parent devices in
635 /devices is not necessarily expected to be stable across kernel releases and
636 searching for parents by their subsystem should make sysfs users tolerant
637 for changed parent chains.
641 Prepare udev to work with the experimental kernel patch, that moves
642 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
644 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
645 moving the class devices to /sys/devices.
647 Thanks again to Marco for help finding a hopefully nice compromise
648 to make %b simpler and working again.
652 Complete removal of libsysfs, replaced by simple helper functions
653 which are much simpler and a bit faster. The udev daemon operatesentirely
654 on event parameters and does not use sysfs for simple rules anymore.
655 Please report any new bugs/problems, that may be caused by this big
656 change. They will be fixed immediately.
658 The enumeration format character '%e' is deprecated and will be
659 removed sometimes from a future udev version. It never worked correctly
660 outside of udevstart, so we can't use it with the new parallel
661 coldplug. A simple enumeration is as useless as the devfs naming
662 scheme, just get rid of both if you still use it.
664 MODALIAS and $modalias is not needed and will be removed from one of
665 the next udev versions, replace it in all rules with ENV{MODALIAS} or
666 the sysfs "modalias" value.
668 Thanks a lot to Marco for all his help on finding and fixing bugs.
672 Let scsi_id request libata drive serial numbers from page 0x80.
674 Renamed etc/udev/persistent.rules to persistent-disk.rules and
675 added /dev/disk/by-name/* for device mapper device names.
677 Removed %e from the man page. It never worked reliably outside
678 of udevstart and udevstart is no longer recommended to use.
682 Symlinks are now exported to the event environment. Hopefully it's no
683 longer needed to run udevinfo from an event process, like it was
684 mentioned on the hotplug list:
685 UDEV [1134776873.702967] add@/block/sdb
688 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
692 Fix a problem if udevsend is used as the hotplug handler and tries to use
693 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
694 and this kind of problems will hopefully go away soon.
698 All built-in logic to work around bad sysfs timing is removed with this
699 version. The need to wait for sysfs files is almost fixed with a kernel
700 version that doesn't work with this udev version anyway. Until we fix
701 the timing of the "bus" link creation, the former integrated logic should
702 be emulated by a rule placed before all other rules:
703 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
705 The option "udev_db" does no longer exist. All udev state will be in
706 /$udev_root/.udev/ now, there is no longer an option to set this
708 If the init script or something else used this value, just depend on
709 this hardcoded path. But remember _all_content_ of this directory is
710 still private to udev and can change at any time.
712 Default location for rule sripts and helper programs is now: /lib/udev/.
713 Everything that is not useful on the commandline should go into this
714 directory. Some of the helpers in the extras folder are installed there
715 now. The rules need to be changed, to find the helpers there.
717 Also /lib/udev/devices is recommended as a directory where packages or
718 the user can place real device nodes, which get copied over to /dev at
719 every boot. This should replace the various solutions with custom config
722 Udevsend does no longer start the udev daemon. This must be done with
723 the init script that prepares /dev on tmpfs and creates the initial nodes,
724 before starting the daemon.
728 Silent a too verbose error logging for the old hotplug.d/ dev.d/
731 The copy of klibc is removed. A systemwide installed version of klibc
732 should be used to build a klibc udev now.
736 NAME="" will not create any nodes, but execute RUN keys. To completely
737 ignore an event the OPTION "ignore_device" should be used.
739 After removal of the reorder queue, events with a TIMEOUT can be executed
740 without any queuing now.
744 Fixed bug in udevd, if inotify is not available. We depend on netlink
745 uevents now, kernels without that event source will not work with that
746 version of udev anymore.
750 The rule parsing happens now in the daemon once at startup, all udev
751 event processes inherit the already parsed rules from the daemon.
752 It is shipped with SUSE10.0 and reduces heavily the system load at
753 startup. The option to save precompiled rules and let the udev process
754 pick the them up is removed, as it's no longer needed.
756 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
757 device. Libsysfs is changed to "translate" the requested link into the
758 real device path, as it would happen with the hotplug event. Otherwise
759 device removal and the udev database will not work.
761 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
764 A few improvements for vol_id, the filesytem probing code.
768 Fix a stupid typo in extras/run_directory for "make install".
770 scsi_id creates the temporary devnode now in /dev for usage with a
771 non-writable /tmp directory.
773 The uevent kernel socket buffer can carry app. 50.000 events now,
774 let's see who can break this again. :)
776 The upcoming kernel will have a new input driver core integration.
777 Some class devices are now symlinks to the real device. libsysfs
778 needs a fix for this to work correctly. Udevstart of older udev
779 versions will _not_ create these devices!
783 Fix a 'install' target in the Makefile, that prevents EXTRAS from
788 A bunch of mostly trivial bugfixes. From now on no node name or
789 symlink name can contain any character than plain whitelisted ascii
790 characters or validated utf8 byte-streams. This is needed for the
791 /dev/disk/by-label/* links, because we import untrusted data and
792 export it to the filesystem.
796 More bugfixes. If udevd was started from the kernel, we don't
797 have stdin/stdout/stderr, which broke the forked tools in some
802 Bugfix. udevstart event ordering was broken for a long time.
803 The new run_program() uncovered it, because /dev/null was not
804 available while we try to run external programs.
805 Now udevstart should create it before we run anything.
809 Minor bugfixes and some distro rules updates. If you don't have the
810 persistent disk rules in /dev/disk/by-*/* on your distro, just
811 grab it from here. :)
815 We can use socket communication now to pass events from udev to
817 RUN+="socket:/org/freedesktop/hal/udev_event"
818 will pass the whole udev event to the HAL daemon without the need
819 for a forked helper. (See ChangeLog for udevmonitor, as an example)
823 Mostly bugfixes and see ChangeLog.
825 The test for the existence of an environment value should be
827 ENV{KEY}=="*" to ENV{KEY}=="?*"
828 because "*" will not fail anymore, if the key does not exist or
833 Bugfixes and a few tweaks described in the ChangeLog.
837 Mostly a Bugfix release.
839 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
840 timing with custom rules.
844 We changed the internal rule storage format. Our large rule files took
845 2 MB of RAM, with the change we are down to 99kB.
847 If the device-node has been created with default name and no symlink or
848 options are to remenber, it is not longer stored in the udevdb. HAL will
849 need to be updated to work correctly with that change.
851 To overrride optimization flags, OPTFLAGS may be used now.
859 Major changes happened with this release. The goal is to take over the
860 complete kernel-event handling and provide a more efficient way to dispatch
861 kernel events. Replacing most of the current shell script logic and the
862 kernel forked helper with a netlink-daemon and a rule-based event handling.
864 o udevd listens to netlink events now. The first valid netlink event
865 will make udevd ignore any message from udevsend that contains a
866 SEQNUM, to avoid duplicate events. The forked events can be disabled
868 echo "" > /proc/sys/kernel/hotplug
869 For full support, the broken input-subsytem needs to be fixed, not to
870 bypass the driver core.
872 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
873 removed from udev itself and must be emulated by calling small
874 helper binaries provided in the extras folder:
875 make EXTRAS=extras/run_directory/
876 will build udev_run_devd and udev_run_hotplugd, which can be called
877 from a rule if needed:
878 RUN+="/sbin/udev_run_hotplugd"
879 The recommended way to handle this is to convert all the calls from
880 the directories to explicit udev rules and get completely rid of the
881 multiplexing. (To catch a ttyUSB event, you now no longer need to
882 fork and exit 300 tty script instances you are not interested in, it
883 is just one rule that matches exactly the device.)
885 o udev handles now _all_ events not just events for class and block
886 devices, this way it is possible to control the complete event
887 behavior with udev rules. Especially useful for rules like:
888 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
890 o As used in the modalias rule, udev supports now textual
891 substitution placeholder along with the usual format chars. This
892 needs to be documented, for now it's only visible in udev_rules_parse.c.
894 o The rule keys support now more operations. This is documented in the
895 man page. It is possible to add values to list-keys like the SYMLINK
896 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
897 Also "final"-assignments are supported by using KEY:="value", which will
898 prevent changing the key by any later rule.
900 o kernel 2.6.12 has the "detached_state" attribute removed from
901 sysfs, which was used to recognize sysfs population. We switched that
902 to wait for the "bus" link, which is only available in kernels after 2.6.11.
903 Running this udev version on older kernels may cause a short delay for
906 o To provide infrastructure for persistent device naming, the id programs:
907 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
908 to export the probed data in environment key format:
909 pim:~ # /sbin/ata_id --export /dev/hda
910 ID_MODEL=HTS726060M9AT00
911 ID_SERIAL=MRH401M4G6UM9B
915 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
916 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
919 kay@pim:~> tree /dev/disk
922 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
923 | `-- IBM-Memory_Key -> ../../sda
925 | |-- swap -> ../../hda1
926 | |-- date -> ../../sda1
927 | `-- home -> ../../hda3
929 |-- 2E08712B0870F2E7 -> ../../hda3
930 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
931 |-- E845-7A89 -> ../../sda1
932 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
934 The IMPORT= operation will import these keys in the environment and make
935 it available for later PROGRAM= and RUN= executed programs. The keys are
936 also stored in the udevdb and can be queried from there with one of the
939 o A few binaries are silently added to the repository, which can be used
940 to replay kernel events from initramfs instead of using coldplug. udevd
941 can be instructed now to queue-up events while the stored events from
942 initramfs are filled into the udevd-queue. This code is still under
943 development and there is no documentation now besides the code itself.
944 The additional binaries get compiled, but are not installed by default.
946 o There is also a temporary fix for a performance problem where too many
947 events happen in parallel and every event needs to parse the rules.
948 udev can now read precompiled rules stored on disk. This is likely to be
949 replaced by a more elegant solution in a future udev version.
953 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
954 Fix for libsysfs not to expect this file was added.
958 All rules are applied now, but only the first matching rule with a NAME-key
959 will be applied. All later rules with NAME-key are completely ignored. This
960 way system supplied symlinks or permissions gets applied to user-defined
964 Please check your rules setup, if you may need to add OPTIONS="last_rule"
965 to some rules, to keep the old behavior.
967 The rules are read on "remove"-events too. That makes is possible to match
968 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
969 instruct udev to ignore an event (OPTIONS="ignore_device").
970 The new ACTION-key may be used to let a rule act only at a "remove"-event.
972 The new RUN-key supports rule-based execution of programs after device-node
973 handling. This is meant as a general replacement for the dev.d/-directories
974 to give fine grained control over the execution of programs.
976 The %s{}-sysfs format char replacement values are searched at any of the
977 devices in the device chain now, not only at the class-device.
979 We support log priority levels now. The value udev_log in udev.conf is used
980 to determine what is printed to syslog. This makes it possible to
981 run a version with compiled-in debug messages in a production environment
982 which is sometimes needed to find a bug.
983 It is still possible to supress the inclusion of _any_ syslog usage with
984 USE_LOG=false to create the smallest possible binaries if needed.
985 The configured udev_log value can be overridden with the environment variable
990 Possible use of a system-wide klibc:
991 make USE_KLIBC=true KLCC=/usr/bin/klcc all
992 will link against an external klibc and our own version will be ignored.
996 We support an unlimited count of symlinks now.
998 If USE_STATIC=true is passed to a glibc build, we link statically and use
999 a built-in userdb parser to resolve user and group names.
1001 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
1002 we walk up the chain of physical devices to find a match.
1004 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
1005 easy to skip certain attribute matches without composing rules with weird
1006 character class negations like:
1007 KERNEL="[!s][!c][!d]*"
1008 this can now be replaced with:
1010 The current simple '=' is still supported, and should work as it does today,
1011 but existing rules should be converted if possible, to be better readable.
1013 We have new ENV{}== key now, to match against a maximum of 5 environment
1016 udevstart is its own binary again, because we don't need co carry this araound
1017 with every forked event.
~ianmdlvl / elogind.git / blob