9 The installed watch for block device metadata changes is now removed
10 during event hadling, because some (broken) tools may be called from udev
11 rules and (wrongly) open the device with write access. After the finished
12 event handling the watch is restored.
18 Device nodes can be watched for changes with inotify with OPTIONS="watch".
19 If closed after being opened for writing, a "change" uevent will occur.
20 /dev/disk/by-{label,uuid}/* symlinks will be automatically updated.
26 The udevadm test command has no longer a --force option, nodes and symlinks
27 are always updated with a test run now.
29 The udevd daemon can be started with --resolve-names=never to avoid all user
30 and group lookups (e.g. in cut-down systems) or --resolve-names=late to
31 lookup user and groups every time events are handled.
37 We are currently merging the Ubuntu rules in the udev default rules,
38 and get one step closer to provide a common Linux /dev setup, regarding
39 device names, symlinks, and default device permissions. On udev startup,
40 we now expect the following groups to be resolvable to their ids with
42 disk, cdrom, floppy, tape, audio, video, lp, tty, dialout, kmem.
43 LDAP setups need to make sure, that these groups are always resolvable at
44 bootup, with only the rootfs mounted, and without network access available.
46 Some systems may need to add some new, currently not used groups, or need
47 to add some users to new groups, but the cost of this change is minimal,
48 compared to the pain the current, rather random, differences between the
49 various distributions cause for upstream projects and third-party vendors.
51 In general, "normal" users who log into a machine should never be a member
52 of any such group, but the device-access should be managed by dynamic ACLs,
53 which get added and removed for the specific users on login/logout and
54 session activity/inactivity. These groups are only provided for custom setups,
55 and mainly system services, to allow proper privilege separation.
56 A video-streaming daemon uid would be a member of "audio" and "video", to get
57 access to the sound and video devices, but no "normal" user should ever belong
58 to the "audio" group, because he could listen to the built-in microphone with
59 any ssh-session established from the other side of the world.
61 /dev/serial/by-{id,path}/ now contains links for ttyUSB devices,
62 which do not depend on the kernel device name. As usual, unique
63 devices - only a single one per product connected, or a real
64 USB serial number in the device - are always found with the same
65 name in the by-id/ directory.
66 Completely identical devices may overwrite their names in by-id/
67 and can only be found reliably in the by-path/ directory. Devices
68 specified by by-path/ must not change their connection, like the
69 USB port number they are plugged in, to keep their name.
71 To support some advanced features, Linux 2.6.22 is the oldest supported
72 version now. The kernel config with enabled SYSFS_DEPRECATED is no longer
73 supported. Older kernels should still work, and devices nodes should be
74 reliably created, but some rules and libudev will not work correctly because
75 the old kernels do not provide the expected information or interfaces.
81 Fix for a possible segfault while swapping network interface names in udev
88 The group "video" is part of the default rules now.
92 Bugfix for kernels using SYSFS_DEPRECATED* option and finding parent
93 block devices in some cases. No common distro uses this option anymore,
94 and we do not get enough testing for this and recent udev versions. If
95 this option is not needed to run some old distro with a new kernel,
96 it should be disabled in the kernel config.
98 Bugfix for the $links substitution variable, which may crash if no links
99 are created. This should not happen in usual setups because we always
100 create /dev/{block,char}/ links.
102 The strings of the parsed rules, which are kept in memory, no longer
103 contain duplicate entries, or duplicate tails of strings. This, and the
104 new rules parsing/matching code reduces the total in-memory size of
105 a huge distro rule sets to 0.08 MB, compared to the 1.2MB of udev
108 The export of DEVTYPE=disk/partition got removed from the default
109 rules. This value is available from the kernel. The pnp shell script
110 modprobe hack is removed from the default rules. ACPI devices have _proper_
111 modalias support and take care of the same functionality.
112 Installations which support old kernels, but install current default
113 udev rules may want to add that to the compat rules file.
115 Libvolume_id now always probes for all known filesystems, and does not
116 stop at the first match. Some filesystems are marked as "exclusive probe",
117 and if any other filesytem type matches at the same time, libvolume_id
118 will, by default, not return any probing result. This is intended to prevent
119 mis-detection with conflicting left-over signatures found from earlier
120 file system formats. That way, we no longer depend on the probe-order
121 in case of multiple competing signatures. In some setups the kernel allows
122 to mount a volume with just the old filesystem signature still in place.
123 This may damage the new filesystem and cause data-loss, just by mounting
124 it. Because volume_id can not decide which one the correct signature is,
125 the wrong signatures need to be removed manually from the volume, or the
126 volume needs to be reformatted, to enable filesystem detection and possible
131 Fix segfault if compiled without optimization and dbg() does not get
132 compiled out and uses variables which are not available.
136 Bugfixes. (And maybe new bugs. :))
138 The rule matching engine got converted from a rule list to a token
139 array which reduced the in-memory rules representation of a full
140 featured distros with thousends of udev rules from 1.2MB to 0.12 MB.
141 Limits like 5 ENV and ATTR matches, and one single instance for most
142 other keys per rule are gone.
144 The NAME assignment is no longer special cased. If later rules assign
145 a NAME value again, the former value will be overwritten. As usual
146 for most other keys, the NAME value can be protected by doing a final
147 assignment with NAME:="<value>".
149 All udev code now uses libudev, which is also exported. The library
150 is still under development, marked as experimental, and its interface
151 may change as long as the DeviceKit integration is not finished.
153 Many thanks to Alan Jenkins for his continuous help, and finding and
154 optimizing some of the computing expensive parts.
160 Kernel devices and device nodes are connected now by reverse indizes in
161 /sys and /dev. A device number retrieved by a stat() or similar, the
162 kernel device directory can be found by looking up:
163 /sys/dev/{block,char}/<maj>:<min>
164 and the device node of the same device by looking up:
165 /dev/{block,char}/<maj>:<min>
169 Fix recently introduced bug, which caused a compilation without large
170 file support, where vol_id does not recognize raid signatures at the end
173 Firewire disks now create both, by-id/scsi-* and by-id/ieee-* links.
174 Seems some kernel versions prevent the creation of the ieee-* links,
175 so people used the scsi-* link which disappeared now.
177 More libudev work. Almost all udevadm functionality comes from libudev
180 udevadm trigger has a new option --type, which allows to trigger events
181 for "devices", for "subsystems", or "failed" devices. The old option
182 --retry-failed" still works, but is no longer mentioned in the man page.
188 The udevadm info --device-id-of-file= output has changed to use
189 the obvious format. Possible current users should use the --export
190 option which is not affected.
192 The old udev commands symlinks to udevadm are not installed, if
193 these symlinks are used, a warning is printed.
199 Optical drive's media is no longer probed for raid signatures,
200 reading the end of the device causes some devices to malfunction.
201 Also the offset of the last session found is used now to probe
204 The volume_id library got a major version number update to 1,
205 some deprecated functions are removed.
207 A shared library "libudev" gets installed now to provide access
208 to udev device information. DeviceKit, the successor of HAL, will
209 need this library to access the udev database and search sysfs for
211 The library is currently in an experimental state, also the API is
212 expected to change, as long as the DeviceKit integration is not
217 We use ./configure now. See INSTALL for details. Current
220 "/usr" - prefix for man pages, include files
222 "" - the root filesystem, prefix for libs and binaries
226 "lib" - directory name for libraries, not a path name
227 multilib 64bit systems may use "lib64" instead of "lib"
229 compile-in verbose debug messages
231 disable all logging and compile-out all log strings
233 link against SELInux libraries, to set the expected context
236 In the default rules, the group "disk" gets permissions 0660 instead
237 of 0640. One small step closer to unify distro rules. Some day, all
238 distros hopefully end up with the same set of rules.
240 No symlinks to udevadm are installed anymore, if they are still needed,
241 they should be provided by the package.
247 Default udev rules, which are not supposed to be edited by the user, should
248 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
249 the udev package and will be replaced with an update. Udev will pick up rule
251 /lib/udev/rules.d/ - default installed rules
252 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
253 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
254 It does not matter in which directory a rule file lives, all files are sorted
257 To help creating /dev/root, we have now:
258 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
261 In case the current --device-id-of-file is already used, please switch to
262 the --export format version, it saves the output parsing and the old
263 format will be changed to use ':' as a separator, like the format in the
268 Fix cdrom_id to properly recognize blank media.
274 Tape drive id-data is queried from /dev/bsg/* instead of the tape
275 nodes. This avoids rewinding tapes on open().
281 The symlinks udevcontrol and udevtrigger are no longer installed by
284 The scsi_id program does not depend on sysfs anymore. It can speak
285 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
286 data, which should solve some old problems with tape devices, where
287 we better do not open all tape device nodes to identify the device.
293 The cdrom_id program is replaced by an advanced version, which can
294 detect most common device types, and also properties of the inserted
295 media. This is part of moving some basic functionality from HAL into
296 udev (and the kernel).
302 The last WAIT_FOR_SYSFS rule is removed from the default rules.
304 The symlinks to udevadm for the debugging tools: udevmonitor and
305 udevtest are no longer created.
307 The symlinks to the udevadm man page for the old tool names are
310 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
311 should be prefixed with '@' to indicate that the path is not a
322 Udevstart is removed from the tree, it did not get installed for
323 a long time now, and is long replaced by trigger and settle.
329 All udev tools are merged into a single binary called udevadm.
330 The old names of the tools are built-in commands in udevadm now.
331 Symlinks to udevadm, with the names of the old tools, provide
332 the same functionality as the standalone tools. There is also
333 only a single udevadm.8 man page left for all tools.
335 Tools like mkinitramfs should be checked, if they need to include
336 udevadm in the list of files.
346 The etc/udev/rules.d/ directory now contains a default set of basic
347 udev rules. This initial version is the result of a rules file merge
348 of Fedora and openSUSE. For these both distros only a few specific
349 rules are left in their own file, named after the distro. Rules which
350 are optionally installed, because they are only valid for a specific
351 architecture, or rules for subsystems which are not always used are
352 in etc/udev/packages/.
358 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
359 actions by dynamically created rules.
361 SYMLINK=="<value>" matches agains the entries in the list of
362 currently defined symlinks. The links are not created in the
363 filesystem at that point in time, but the values can be matched.
365 RUN{ignore_error}+="<program>" will ignore any exit code from the
366 program and not record as a failed event.
372 Final merge of patches/features from the Ubuntu package.
378 Control characters in filesystem label strings are no longer silenty
379 removed, but hex-encoded, to be able to uniquely identify the device
380 by its symlink in /dev/disk/by-label/.
381 If libvolume_id is used by mount(8), LABEL= will work as expected,
382 if slashes or other characters are used in the label string.
384 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
385 can be specified now. The TEST key accepts an optional mode mask
386 TEST{0100}=="<is executable file>".
388 Scsi_id now supports a mode without expecting scsi-specific sysfs
389 entries to allow the extraction of cciss-device persistent properties.
395 In the future, we may see uuid's which are just simple character
396 strings (see the DDF Raid Specification). For that reason vol_id now
397 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
398 the creation of symlinks, the *_SAFE values ensure, that no control
399 or whitespace characters are used in the filename.
401 Possible users of libvolume_id, please use the volume_id_get_* functions.
402 The public struct will go away in a future release of the library.
408 Removal of useless extras/eventrecorder.sh.
418 The directory multiplexer for dev.d/ and hotplug.d are finally removed
419 from the udev package.
425 Symlinks can have priorities now, the priority is assigned to the device
426 and specified with OPTIONS="link_priority=100". Devices with higher
427 priorities overwrite the symlinks of devices with lower priorities.
428 If the device that currently owns the link, goes away, the symlink
429 will be removed, and recreated, pointing to the next device with the
430 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
431 more reliable, if multiple devices contain the same metadata and overwrite
434 The dasd_id program is removed from the udev tree, and dasdinfo, with the
435 needed rules, are part of the s390-tools now.
437 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
438 we may get the scsi sysfs mess fixed some day, and this will only catch
439 the devices we are looking for.
441 USB serial numbers for storage devices have the target:lun now appended,
442 to make it possibble to distinguish broken multi-lun devices with all
443 the same SCSI identifiers.
445 Note: The extra "run_directory" which searches and executes stuff in
446 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
447 with the next release. Make sure, that you don't use it anymore, or
448 provides your own implementation of that inefficient stuff.
449 We are tired of reports about a "slow udev", because these directories
450 contain stuff, that runs with _every_ event, instead of using rules,
451 that run programs only for the matching events.
461 DRIVER== will match only for devices that actually have a real
462 driver. DRIVERS== must be used, if parent devices should be
463 included in the match.
465 Libvolume_id's "linux_raid" detection needed another fix.
473 Add additional check to volume_id detection of via_raid, cause
474 some company decided to put a matching pattern all over the empty
475 storage area of their music players.
479 Fix path_id for SAS devices.
483 The udev daemon can be started with --debug-trace now, which will
484 execute all events serialized to get a chance to catch a possible
485 action that crashes the box.
487 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
488 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
489 are excluded from the warning. Referencing parent attributes directly
490 may break when something in the kernel driver model changes. Udev will
491 just find the attribute by walking up the parent chain.
493 Udevtrigger now sorts the list of devices depending on the device
494 dependency, so a "usb" device is triggered after the parent "pci"
499 Revert persistent-storage ata-serial '_' '-' replacement.
505 Udevtrigger can now filter the list of devices to be triggered. Matches
506 for subsystems or sysfs attributes can be specified.
508 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
509 zero-sized files to avoid pointing to /sys and confuse broken tools which
510 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
513 The rules and scripts to create udev rules for persistent network
514 devices and optical drives are in the extras/rules_generator directory
515 now. If you use something similar, please consider replacing your own
516 version with this, to share the support effort. The rule_generator
517 installs its own rules into /etc/udev/rules.d.
519 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
520 the rule_generator depends on cdrom_id to be called in an earlier rule.
526 Renaming of some key names (the old names still work):
527 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
528 (The behavior of the key DRIVER will change soon in one of the next
529 releases, to match only the event device, please switch to DRIVERS
530 instead. If DRIVER is used, it will behave like DRIVERS, but an error
532 With the new key names, we have a more consistent and simpler scheme.
533 We can match the properties of the event device only, with: KERNEL,
534 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
535 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
536 longer mentioned in the man page and should be switched in the rule
539 ATTR{file}="value" can be used now, to write to a sysfs file of the
540 event device. Instead of:
541 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
543 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
545 All the PHYSDEV* keys are deprecated and will be removed from a
547 PHYDEVPATH - is the path of a parent device and should not be
549 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
550 matched with SUBSYSTEMS==
551 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
552 Newer kernels will have DRIVER in the environment,
553 for older kernels udev puts in. Class device will
554 no longer carry this property of a parent and
555 DRIVERS== can be used to match such a parent value.
556 Note that ENV{DRIVER} is only available for a few bus devices, where
557 the driver is already bound at device event time. On coldplug, the
558 events for a lot devices are already bound to a driver, and they will have
559 that value set. But on hotplug, at the time the kernel creates the device,
560 it can't know what driver may claim the device after that, therefore
561 in most cases it will be empty.
563 Failed events should now be re-triggered with:
564 udevtrigger --retry-failed.
565 Please switch to this command, so we keep the details of the /dev/.udev/failed/
566 files private to the udev tools. We may need to switch the current symlink
567 target, cause some obviously broken tools try to scan all files in /dev
568 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
569 million times. This takes ages on slow boxes.
571 The udevinfo attribute walk (-a) now works with giving a device node
572 name (-n) instead of a devpath (-p). The query now always works, also when
573 no database file was created by udev.
575 The built-in /etc/passwd /etc/group parser is removed, we always depend on
576 getpwnam() and getgrnam() now. One of the next releases will depend on
577 fnmatch() and may use getopt_long().
581 Bugfixes and small improvements.
585 Fix path_id for recent kernels.
591 Added support for swapping network interface names, by temporarily
592 renaming the device and wait for the target name to become free.
596 The built-in MODALIAS key and substitution is removed.
600 The binary firmware helper is replaced by the usual simple
601 shell script. Udevsend is removed from the tree.
609 Some more keys require the correct use of '==' and '=' depending
610 on the kind of operation beeing an assignment or a match. Rules
611 with invalid operations are skipped and logged to syslog. Please
612 test with udevtest if the parsing of your rules throws errors and
613 fix possibly broken rules.
617 Provide "udevsettle" to wait for all current udev events to finish.
618 It also watches the current kernel netlink queue by comparing the
619 even sequence number to make sure that there are no current pending
620 events that have not already arrived in the daemon.
624 Fix rule to skip persistent rules for removable IDE devices, which
625 also skipped optical IDE drives.
627 All *_id program are installed in /lib/udev/ by default now.
629 No binary is stripped anymore as this should be done in the
630 packaging process and not at build time.
632 libvolume_id is provided as a shared library now and vol_id is
633 linked against it. Also one of the next HAL versions will require
634 this library, and the HAL build process will also require the
635 header file to be installed. The copy of the same code in HAL will
636 be removed to have only a single copy left on the system.
640 Add persistent links for SCSI tapes. The rules file is renamed
641 to 60-persistent-storage.rules.
643 Create persistent path for usb devices. Can be used for all sorts
644 of devices that can't be distinguished by other properties like
645 multiple identical keyboards and mice connected to the same box.
647 Provide "udevtrigger" program to request events on coldplug. The
648 shell script is much too slow with thousends of devices.
652 Fix persistent disk rules to exclude removable IDE drives.
654 Warn if %e, $modalias or MODALIAS is used.
658 Fix queue export, which wasn't correct for subsequent add/remove
659 events for the same device.
663 Fix cramfs detection on big endian.
665 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
670 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
671 attributes were only checked at the parent device that matched the
672 by BUS requested subsystem. Fix it to also look at the device we
673 received the event for.
675 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
680 Fix a bug where NAME="" would prevent RUN from beeing executed.
682 RUN="/bin/program" does not longer automatically add the subsystem
683 as the first parameter. This is from the days of /sbin/hotplug
684 which is dead now and it's just confusing to need to add a space at
685 the end of the program name to prevent this.
686 If you use rules that need the subsystem as the first parameter,
687 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
688 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
692 The udev man page has moved to udev(7) as it does not describe a command
693 anymore. The programs udev, udevstart and udevsend are no longer installed
694 by default and must be copied manually, if they should be installed or
695 included in a package.
697 Fix a bug where "ignore_device" could run earlier collected RUN keys before
698 the ignore rule was applied.
700 More preparation for future sysfs changes. usb_id and scsi_id no longer
701 depend on a magic order of devices in the /devices chain. Specific devices
702 should be requested by their subsytem.
704 This will always find the scsi parent device without depending on a specific
706 dev = sysfs_device_get(devpath);
707 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
709 The "device" link in the current sysfs layout will be automatically
710 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
711 parent in the devpath. If a device is requested by it's symlink, like all
712 class devices in the new sysfs layout will look like, it gets automatically
713 resolved and substituted with the real devpath and not the symlink path.
716 A similar logic must be applied to _all_ sysfs users, including
717 scripts, that search along parent devices in sysfs. The explicit use of
718 the "device" link must be avoided. With the future sysfs layout all
719 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
720 back to the "class" or the "bus". The layout of the parent devices in
721 /devices is not necessarily expected to be stable across kernel releases and
722 searching for parents by their subsystem should make sysfs users tolerant
723 for changed parent chains.
727 Prepare udev to work with the experimental kernel patch, that moves
728 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
730 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
731 moving the class devices to /sys/devices.
733 Thanks again to Marco for help finding a hopefully nice compromise
734 to make %b simpler and working again.
738 Complete removal of libsysfs, replaced by simple helper functions
739 which are much simpler and a bit faster. The udev daemon operatesentirely
740 on event parameters and does not use sysfs for simple rules anymore.
741 Please report any new bugs/problems, that may be caused by this big
742 change. They will be fixed immediately.
744 The enumeration format character '%e' is deprecated and will be
745 removed sometimes from a future udev version. It never worked correctly
746 outside of udevstart, so we can't use it with the new parallel
747 coldplug. A simple enumeration is as useless as the devfs naming
748 scheme, just get rid of both if you still use it.
750 MODALIAS and $modalias is not needed and will be removed from one of
751 the next udev versions, replace it in all rules with ENV{MODALIAS} or
752 the sysfs "modalias" value.
754 Thanks a lot to Marco for all his help on finding and fixing bugs.
758 Let scsi_id request libata drive serial numbers from page 0x80.
760 Renamed etc/udev/persistent.rules to persistent-disk.rules and
761 added /dev/disk/by-name/* for device mapper device names.
763 Removed %e from the man page. It never worked reliably outside
764 of udevstart and udevstart is no longer recommended to use.
768 Symlinks are now exported to the event environment. Hopefully it's no
769 longer needed to run udevinfo from an event process, like it was
770 mentioned on the hotplug list:
771 UDEV [1134776873.702967] add@/block/sdb
774 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
778 Fix a problem if udevsend is used as the hotplug handler and tries to use
779 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
780 and this kind of problems will hopefully go away soon.
784 All built-in logic to work around bad sysfs timing is removed with this
785 version. The need to wait for sysfs files is almost fixed with a kernel
786 version that doesn't work with this udev version anyway. Until we fix
787 the timing of the "bus" link creation, the former integrated logic should
788 be emulated by a rule placed before all other rules:
789 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
791 The option "udev_db" does no longer exist. All udev state will be in
792 /$udev_root/.udev/ now, there is no longer an option to set this
794 If the init script or something else used this value, just depend on
795 this hardcoded path. But remember _all_content_ of this directory is
796 still private to udev and can change at any time.
798 Default location for rule sripts and helper programs is now: /lib/udev/.
799 Everything that is not useful on the commandline should go into this
800 directory. Some of the helpers in the extras folder are installed there
801 now. The rules need to be changed, to find the helpers there.
803 Also /lib/udev/devices is recommended as a directory where packages or
804 the user can place real device nodes, which get copied over to /dev at
805 every boot. This should replace the various solutions with custom config
808 Udevsend does no longer start the udev daemon. This must be done with
809 the init script that prepares /dev on tmpfs and creates the initial nodes,
810 before starting the daemon.
814 Silent a too verbose error logging for the old hotplug.d/ dev.d/
817 The copy of klibc is removed. A systemwide installed version of klibc
818 should be used to build a klibc udev now.
822 NAME="" will not create any nodes, but execute RUN keys. To completely
823 ignore an event the OPTION "ignore_device" should be used.
825 After removal of the reorder queue, events with a TIMEOUT can be executed
826 without any queuing now.
830 Fixed bug in udevd, if inotify is not available. We depend on netlink
831 uevents now, kernels without that event source will not work with that
832 version of udev anymore.
836 The rule parsing happens now in the daemon once at startup, all udev
837 event processes inherit the already parsed rules from the daemon.
838 It is shipped with SUSE10.0 and reduces heavily the system load at
839 startup. The option to save precompiled rules and let the udev process
840 pick the them up is removed, as it's no longer needed.
842 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
843 device. Libsysfs is changed to "translate" the requested link into the
844 real device path, as it would happen with the hotplug event. Otherwise
845 device removal and the udev database will not work.
847 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
850 A few improvements for vol_id, the filesytem probing code.
854 Fix a stupid typo in extras/run_directory for "make install".
856 scsi_id creates the temporary devnode now in /dev for usage with a
857 non-writable /tmp directory.
859 The uevent kernel socket buffer can carry app. 50.000 events now,
860 let's see who can break this again. :)
862 The upcoming kernel will have a new input driver core integration.
863 Some class devices are now symlinks to the real device. libsysfs
864 needs a fix for this to work correctly. Udevstart of older udev
865 versions will _not_ create these devices!
869 Fix a 'install' target in the Makefile, that prevents EXTRAS from
874 A bunch of mostly trivial bugfixes. From now on no node name or
875 symlink name can contain any character than plain whitelisted ascii
876 characters or validated utf8 byte-streams. This is needed for the
877 /dev/disk/by-label/* links, because we import untrusted data and
878 export it to the filesystem.
882 More bugfixes. If udevd was started from the kernel, we don't
883 have stdin/stdout/stderr, which broke the forked tools in some
888 Bugfix. udevstart event ordering was broken for a long time.
889 The new run_program() uncovered it, because /dev/null was not
890 available while we try to run external programs.
891 Now udevstart should create it before we run anything.
895 Minor bugfixes and some distro rules updates. If you don't have the
896 persistent disk rules in /dev/disk/by-*/* on your distro, just
897 grab it from here. :)
901 We can use socket communication now to pass events from udev to
903 RUN+="socket:/org/freedesktop/hal/udev_event"
904 will pass the whole udev event to the HAL daemon without the need
905 for a forked helper. (See ChangeLog for udevmonitor, as an example)
909 Mostly bugfixes and see ChangeLog.
911 The test for the existence of an environment value should be
913 ENV{KEY}=="*" to ENV{KEY}=="?*"
914 because "*" will not fail anymore, if the key does not exist or
919 Bugfixes and a few tweaks described in the ChangeLog.
923 Mostly a Bugfix release.
925 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
926 timing with custom rules.
930 We changed the internal rule storage format. Our large rule files took
931 2 MB of RAM, with the change we are down to 99kB.
933 If the device-node has been created with default name and no symlink or
934 options are to remenber, it is not longer stored in the udevdb. HAL will
935 need to be updated to work correctly with that change.
937 To overrride optimization flags, OPTFLAGS may be used now.
945 Major changes happened with this release. The goal is to take over the
946 complete kernel-event handling and provide a more efficient way to dispatch
947 kernel events. Replacing most of the current shell script logic and the
948 kernel forked helper with a netlink-daemon and a rule-based event handling.
950 o udevd listens to netlink events now. The first valid netlink event
951 will make udevd ignore any message from udevsend that contains a
952 SEQNUM, to avoid duplicate events. The forked events can be disabled
954 echo "" > /proc/sys/kernel/hotplug
955 For full support, the broken input-subsytem needs to be fixed, not to
956 bypass the driver core.
958 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
959 removed from udev itself and must be emulated by calling small
960 helper binaries provided in the extras folder:
961 make EXTRAS=extras/run_directory/
962 will build udev_run_devd and udev_run_hotplugd, which can be called
963 from a rule if needed:
964 RUN+="/sbin/udev_run_hotplugd"
965 The recommended way to handle this is to convert all the calls from
966 the directories to explicit udev rules and get completely rid of the
967 multiplexing. (To catch a ttyUSB event, you now no longer need to
968 fork and exit 300 tty script instances you are not interested in, it
969 is just one rule that matches exactly the device.)
971 o udev handles now _all_ events not just events for class and block
972 devices, this way it is possible to control the complete event
973 behavior with udev rules. Especially useful for rules like:
974 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
976 o As used in the modalias rule, udev supports now textual
977 substitution placeholder along with the usual format chars. This
978 needs to be documented, for now it's only visible in udev_rules_parse.c.
980 o The rule keys support now more operations. This is documented in the
981 man page. It is possible to add values to list-keys like the SYMLINK
982 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
983 Also "final"-assignments are supported by using KEY:="value", which will
984 prevent changing the key by any later rule.
986 o kernel 2.6.12 has the "detached_state" attribute removed from
987 sysfs, which was used to recognize sysfs population. We switched that
988 to wait for the "bus" link, which is only available in kernels after 2.6.11.
989 Running this udev version on older kernels may cause a short delay for
992 o To provide infrastructure for persistent device naming, the id programs:
993 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
994 to export the probed data in environment key format:
995 pim:~ # /sbin/ata_id --export /dev/hda
996 ID_MODEL=HTS726060M9AT00
997 ID_SERIAL=MRH401M4G6UM9B
1000 The following rules:
1001 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
1002 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
1005 kay@pim:~> tree /dev/disk
1008 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
1009 | `-- IBM-Memory_Key -> ../../sda
1011 | |-- swap -> ../../hda1
1012 | |-- date -> ../../sda1
1013 | `-- home -> ../../hda3
1015 |-- 2E08712B0870F2E7 -> ../../hda3
1016 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
1017 |-- E845-7A89 -> ../../sda1
1018 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
1020 The IMPORT= operation will import these keys in the environment and make
1021 it available for later PROGRAM= and RUN= executed programs. The keys are
1022 also stored in the udevdb and can be queried from there with one of the
1025 o A few binaries are silently added to the repository, which can be used
1026 to replay kernel events from initramfs instead of using coldplug. udevd
1027 can be instructed now to queue-up events while the stored events from
1028 initramfs are filled into the udevd-queue. This code is still under
1029 development and there is no documentation now besides the code itself.
1030 The additional binaries get compiled, but are not installed by default.
1032 o There is also a temporary fix for a performance problem where too many
1033 events happen in parallel and every event needs to parse the rules.
1034 udev can now read precompiled rules stored on disk. This is likely to be
1035 replaced by a more elegant solution in a future udev version.
1039 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
1040 Fix for libsysfs not to expect this file was added.
1044 All rules are applied now, but only the first matching rule with a NAME-key
1045 will be applied. All later rules with NAME-key are completely ignored. This
1046 way system supplied symlinks or permissions gets applied to user-defined
1050 Please check your rules setup, if you may need to add OPTIONS="last_rule"
1051 to some rules, to keep the old behavior.
1053 The rules are read on "remove"-events too. That makes is possible to match
1054 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
1055 instruct udev to ignore an event (OPTIONS="ignore_device").
1056 The new ACTION-key may be used to let a rule act only at a "remove"-event.
1058 The new RUN-key supports rule-based execution of programs after device-node
1059 handling. This is meant as a general replacement for the dev.d/-directories
1060 to give fine grained control over the execution of programs.
1062 The %s{}-sysfs format char replacement values are searched at any of the
1063 devices in the device chain now, not only at the class-device.
1065 We support log priority levels now. The value udev_log in udev.conf is used
1066 to determine what is printed to syslog. This makes it possible to
1067 run a version with compiled-in debug messages in a production environment
1068 which is sometimes needed to find a bug.
1069 It is still possible to supress the inclusion of _any_ syslog usage with
1070 USE_LOG=false to create the smallest possible binaries if needed.
1071 The configured udev_log value can be overridden with the environment variable
1076 Possible use of a system-wide klibc:
1077 make USE_KLIBC=true KLCC=/usr/bin/klcc all
1078 will link against an external klibc and our own version will be ignored.
1082 We support an unlimited count of symlinks now.
1084 If USE_STATIC=true is passed to a glibc build, we link statically and use
1085 a built-in userdb parser to resolve user and group names.
1087 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
1088 we walk up the chain of physical devices to find a match.
1090 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
1091 easy to skip certain attribute matches without composing rules with weird
1092 character class negations like:
1093 KERNEL="[!s][!c][!d]*"
1094 this can now be replaced with:
1096 The current simple '=' is still supported, and should work as it does today,
1097 but existing rules should be converted if possible, to be better readable.
1099 We have new ENV{}== key now, to match against a maximum of 5 environment
1102 udevstart is its own binary again, because we don't need co carry this araound
1103 with every forked event.
~ianmdlvl / elogind.git / blob