5 Event processes now get re-used after they handled an event. This reduces
6 the number of forks and the pressure on the CPU significantly, because
7 cloned event processes no longer cause page faults in the main daemon.
8 After the events have settled, a few worker processes stay around for
9 future events, all others get cleaned up.
11 To be able to use signalfd(), udev depends on kernel version 2.6.25 now.
12 Also inotify support is mandatory now to run udev.
14 The format of the queue exported by the udev damon has changed. There is
15 no longer a /dev/.udev/queue/ directory. The current event queue can be
16 accessed with udevadm settle and libudedv.
18 Libudev does not have the unstable API header anymore. From now on,
19 incompatible changes will be handled by bumping the library major version.
21 To build udev from the git tree gtk-doc is needed now. The tarballs will
22 build without it and contain the pre-built documentation. An online copy
24 http://www.kernel.org/pub/linux/utils/kernel/hotplug/libudev/
26 Many extras of the udev-extras repository have been merged into the main
27 udev repository. Some of the extras have larger external dependencies, and
28 they can be disabled with the configure switch --disable-extras.
34 The program vol_id and the library libvolume_id are removed from the
35 repository. Libvolume_id is merged with libblkid from the util-linux-ng
36 package. Persistent disk links for label and uuid depend on the
37 util-linux-ng version (2.15) of blkid now. Older versions of blkid
38 can not be used with udev.
40 Libudev allows to subscribe to udev events. To prevent unwanted messages
41 to be delivered, and waking up the subscribing process, a filter can be
42 installed, to drop messages inside a kernel socket filter. The filters
43 match on the <subsytem>:<devtype> properties of the device.
44 This is part of the ongoing effort to replace HAL, and switch current
45 users over to directly use libudev.
46 Libudev is still marked as experimental, and its interface might
47 eventually change if needed, but no major changes of the currently exported
48 interface are expected anymore, and a first stable release should happen
51 A too old kernel (2.6.21) or a kernel with CONFIG_SYSFS_DEPRECATED
52 is not supported since while and udevd will log an error message at
53 startup. It should still be able to boot-up, but advanced rules and system
54 services which depend on the information not available in the old sysfs
55 format will fail to work correctly.
57 DVB device naming is supplied by the kernel now. In case older kernels
58 need to be supported, the old shell script should be added to a compat
65 The processed udev events get send back to the netlink socket. Libudev
66 provides access to these events. This is work-in-progress, to replace
67 the DeviceKit daemon functionality directly with libudev. There are
68 upcoming kernel changes to allow non-root users to subcribe to these
75 "udevadm settle" now optionally accepts a range of events to wait for,
76 instead of waiting for "all" events.
82 The installed watch for block device metadata changes is now removed
83 during event hadling, because some (broken) tools may be called from udev
84 rules and (wrongly) open the device with write access. After the finished
85 event handling the watch is restored.
91 Device nodes can be watched for changes with inotify with OPTIONS="watch".
92 If closed after being opened for writing, a "change" uevent will occur.
93 /dev/disk/by-{label,uuid}/* symlinks will be automatically updated.
99 The udevadm test command has no longer a --force option, nodes and symlinks
100 are always updated with a test run now.
102 The udevd daemon can be started with --resolve-names=never to avoid all user
103 and group lookups (e.g. in cut-down systems) or --resolve-names=late to
104 lookup user and groups every time events are handled.
110 We are currently merging the Ubuntu rules in the udev default rules,
111 and get one step closer to provide a common Linux /dev setup, regarding
112 device names, symlinks, and default device permissions. On udev startup,
113 we now expect the following groups to be resolvable to their ids with
115 disk, cdrom, floppy, tape, audio, video, lp, tty, dialout, kmem.
116 LDAP setups need to make sure, that these groups are always resolvable at
117 bootup, with only the rootfs mounted, and without network access available.
119 Some systems may need to add some new, currently not used groups, or need
120 to add some users to new groups, but the cost of this change is minimal,
121 compared to the pain the current, rather random, differences between the
122 various distributions cause for upstream projects and third-party vendors.
124 In general, "normal" users who log into a machine should never be a member
125 of any such group, but the device-access should be managed by dynamic ACLs,
126 which get added and removed for the specific users on login/logout and
127 session activity/inactivity. These groups are only provided for custom setups,
128 and mainly system services, to allow proper privilege separation.
129 A video-streaming daemon uid would be a member of "audio" and "video", to get
130 access to the sound and video devices, but no "normal" user should ever belong
131 to the "audio" group, because he could listen to the built-in microphone with
132 any ssh-session established from the other side of the world.
134 /dev/serial/by-{id,path}/ now contains links for ttyUSB devices,
135 which do not depend on the kernel device name. As usual, unique
136 devices - only a single one per product connected, or a real
137 USB serial number in the device - are always found with the same
138 name in the by-id/ directory.
139 Completely identical devices may overwrite their names in by-id/
140 and can only be found reliably in the by-path/ directory. Devices
141 specified by by-path/ must not change their connection, like the
142 USB port number they are plugged in, to keep their name.
144 To support some advanced features, Linux 2.6.22 is the oldest supported
145 version now. The kernel config with enabled SYSFS_DEPRECATED is no longer
146 supported. Older kernels should still work, and devices nodes should be
147 reliably created, but some rules and libudev will not work correctly because
148 the old kernels do not provide the expected information or interfaces.
154 Fix for a possible segfault while swapping network interface names in udev
161 The group "video" is part of the default rules now.
165 Bugfix for kernels using SYSFS_DEPRECATED* option and finding parent
166 block devices in some cases. No common distro uses this option anymore,
167 and we do not get enough testing for this and recent udev versions. If
168 this option is not needed to run some old distro with a new kernel,
169 it should be disabled in the kernel config.
171 Bugfix for the $links substitution variable, which may crash if no links
172 are created. This should not happen in usual setups because we always
173 create /dev/{block,char}/ links.
175 The strings of the parsed rules, which are kept in memory, no longer
176 contain duplicate entries, or duplicate tails of strings. This, and the
177 new rules parsing/matching code reduces the total in-memory size of
178 a huge distro rule sets to 0.08 MB, compared to the 1.2MB of udev
181 The export of DEVTYPE=disk/partition got removed from the default
182 rules. This value is available from the kernel. The pnp shell script
183 modprobe hack is removed from the default rules. ACPI devices have _proper_
184 modalias support and take care of the same functionality.
185 Installations which support old kernels, but install current default
186 udev rules may want to add that to the compat rules file.
188 Libvolume_id now always probes for all known filesystems, and does not
189 stop at the first match. Some filesystems are marked as "exclusive probe",
190 and if any other filesytem type matches at the same time, libvolume_id
191 will, by default, not return any probing result. This is intended to prevent
192 mis-detection with conflicting left-over signatures found from earlier
193 file system formats. That way, we no longer depend on the probe-order
194 in case of multiple competing signatures. In some setups the kernel allows
195 to mount a volume with just the old filesystem signature still in place.
196 This may damage the new filesystem and cause data-loss, just by mounting
197 it. Because volume_id can not decide which one the correct signature is,
198 the wrong signatures need to be removed manually from the volume, or the
199 volume needs to be reformatted, to enable filesystem detection and possible
204 Fix segfault if compiled without optimization and dbg() does not get
205 compiled out and uses variables which are not available.
209 Bugfixes. (And maybe new bugs. :))
211 The rule matching engine got converted from a rule list to a token
212 array which reduced the in-memory rules representation of a full
213 featured distros with thousends of udev rules from 1.2MB to 0.12 MB.
214 Limits like 5 ENV and ATTR matches, and one single instance for most
215 other keys per rule are gone.
217 The NAME assignment is no longer special cased. If later rules assign
218 a NAME value again, the former value will be overwritten. As usual
219 for most other keys, the NAME value can be protected by doing a final
220 assignment with NAME:="<value>".
222 All udev code now uses libudev, which is also exported. The library
223 is still under development, marked as experimental, and its interface
224 may change as long as the DeviceKit integration is not finished.
226 Many thanks to Alan Jenkins for his continuous help, and finding and
227 optimizing some of the computing expensive parts.
233 Kernel devices and device nodes are connected now by reverse indizes in
234 /sys and /dev. A device number retrieved by a stat() or similar, the
235 kernel device directory can be found by looking up:
236 /sys/dev/{block,char}/<maj>:<min>
237 and the device node of the same device by looking up:
238 /dev/{block,char}/<maj>:<min>
242 Fix recently introduced bug, which caused a compilation without large
243 file support, where vol_id does not recognize raid signatures at the end
246 Firewire disks now create both, by-id/scsi-* and by-id/ieee-* links.
247 Seems some kernel versions prevent the creation of the ieee-* links,
248 so people used the scsi-* link which disappeared now.
250 More libudev work. Almost all udevadm functionality comes from libudev
253 udevadm trigger has a new option --type, which allows to trigger events
254 for "devices", for "subsystems", or "failed" devices. The old option
255 --retry-failed" still works, but is no longer mentioned in the man page.
261 The udevadm info --device-id-of-file= output has changed to use
262 the obvious format. Possible current users should use the --export
263 option which is not affected.
265 The old udev commands symlinks to udevadm are not installed, if
266 these symlinks are used, a warning is printed.
272 Optical drive's media is no longer probed for raid signatures,
273 reading the end of the device causes some devices to malfunction.
274 Also the offset of the last session found is used now to probe
277 The volume_id library got a major version number update to 1,
278 some deprecated functions are removed.
280 A shared library "libudev" gets installed now to provide access
281 to udev device information. DeviceKit, the successor of HAL, will
282 need this library to access the udev database and search sysfs for
284 The library is currently in an experimental state, also the API is
285 expected to change, as long as the DeviceKit integration is not
290 We use ./configure now. See INSTALL for details. Current
293 "/usr" - prefix for man pages, include files
295 "" - the root filesystem, prefix for libs and binaries
299 "lib" - directory name for libraries, not a path name
300 multilib 64bit systems may use "lib64" instead of "lib"
302 compile-in verbose debug messages
304 disable all logging and compile-out all log strings
306 link against SELInux libraries, to set the expected context
309 In the default rules, the group "disk" gets permissions 0660 instead
310 of 0640. One small step closer to unify distro rules. Some day, all
311 distros hopefully end up with the same set of rules.
313 No symlinks to udevadm are installed anymore, if they are still needed,
314 they should be provided by the package.
320 Default udev rules, which are not supposed to be edited by the user, should
321 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
322 the udev package and will be replaced with an update. Udev will pick up rule
324 /lib/udev/rules.d/ - default installed rules
325 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
326 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
327 It does not matter in which directory a rule file lives, all files are sorted
330 To help creating /dev/root, we have now:
331 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
334 In case the current --device-id-of-file is already used, please switch to
335 the --export format version, it saves the output parsing and the old
336 format will be changed to use ':' as a separator, like the format in the
341 Fix cdrom_id to properly recognize blank media.
347 Tape drive id-data is queried from /dev/bsg/* instead of the tape
348 nodes. This avoids rewinding tapes on open().
354 The symlinks udevcontrol and udevtrigger are no longer installed by
357 The scsi_id program does not depend on sysfs anymore. It can speak
358 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
359 data, which should solve some old problems with tape devices, where
360 we better do not open all tape device nodes to identify the device.
366 The cdrom_id program is replaced by an advanced version, which can
367 detect most common device types, and also properties of the inserted
368 media. This is part of moving some basic functionality from HAL into
369 udev (and the kernel).
375 The last WAIT_FOR_SYSFS rule is removed from the default rules.
377 The symlinks to udevadm for the debugging tools: udevmonitor and
378 udevtest are no longer created.
380 The symlinks to the udevadm man page for the old tool names are
383 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
384 should be prefixed with '@' to indicate that the path is not a
395 Udevstart is removed from the tree, it did not get installed for
396 a long time now, and is long replaced by trigger and settle.
402 All udev tools are merged into a single binary called udevadm.
403 The old names of the tools are built-in commands in udevadm now.
404 Symlinks to udevadm, with the names of the old tools, provide
405 the same functionality as the standalone tools. There is also
406 only a single udevadm.8 man page left for all tools.
408 Tools like mkinitramfs should be checked, if they need to include
409 udevadm in the list of files.
419 The etc/udev/rules.d/ directory now contains a default set of basic
420 udev rules. This initial version is the result of a rules file merge
421 of Fedora and openSUSE. For these both distros only a few specific
422 rules are left in their own file, named after the distro. Rules which
423 are optionally installed, because they are only valid for a specific
424 architecture, or rules for subsystems which are not always used are
425 in etc/udev/packages/.
431 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
432 actions by dynamically created rules.
434 SYMLINK=="<value>" matches agains the entries in the list of
435 currently defined symlinks. The links are not created in the
436 filesystem at that point in time, but the values can be matched.
438 RUN{ignore_error}+="<program>" will ignore any exit code from the
439 program and not record as a failed event.
445 Final merge of patches/features from the Ubuntu package.
451 Control characters in filesystem label strings are no longer silenty
452 removed, but hex-encoded, to be able to uniquely identify the device
453 by its symlink in /dev/disk/by-label/.
454 If libvolume_id is used by mount(8), LABEL= will work as expected,
455 if slashes or other characters are used in the label string.
457 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
458 can be specified now. The TEST key accepts an optional mode mask
459 TEST{0100}=="<is executable file>".
461 Scsi_id now supports a mode without expecting scsi-specific sysfs
462 entries to allow the extraction of cciss-device persistent properties.
468 In the future, we may see uuid's which are just simple character
469 strings (see the DDF Raid Specification). For that reason vol_id now
470 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
471 the creation of symlinks, the *_SAFE values ensure, that no control
472 or whitespace characters are used in the filename.
474 Possible users of libvolume_id, please use the volume_id_get_* functions.
475 The public struct will go away in a future release of the library.
481 Removal of useless extras/eventrecorder.sh.
491 The directory multiplexer for dev.d/ and hotplug.d are finally removed
492 from the udev package.
498 Symlinks can have priorities now, the priority is assigned to the device
499 and specified with OPTIONS="link_priority=100". Devices with higher
500 priorities overwrite the symlinks of devices with lower priorities.
501 If the device that currently owns the link, goes away, the symlink
502 will be removed, and recreated, pointing to the next device with the
503 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
504 more reliable, if multiple devices contain the same metadata and overwrite
507 The dasd_id program is removed from the udev tree, and dasdinfo, with the
508 needed rules, are part of the s390-tools now.
510 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
511 we may get the scsi sysfs mess fixed some day, and this will only catch
512 the devices we are looking for.
514 USB serial numbers for storage devices have the target:lun now appended,
515 to make it possibble to distinguish broken multi-lun devices with all
516 the same SCSI identifiers.
518 Note: The extra "run_directory" which searches and executes stuff in
519 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
520 with the next release. Make sure, that you don't use it anymore, or
521 provides your own implementation of that inefficient stuff.
522 We are tired of reports about a "slow udev", because these directories
523 contain stuff, that runs with _every_ event, instead of using rules,
524 that run programs only for the matching events.
534 DRIVER== will match only for devices that actually have a real
535 driver. DRIVERS== must be used, if parent devices should be
536 included in the match.
538 Libvolume_id's "linux_raid" detection needed another fix.
546 Add additional check to volume_id detection of via_raid, cause
547 some company decided to put a matching pattern all over the empty
548 storage area of their music players.
552 Fix path_id for SAS devices.
556 The udev daemon can be started with --debug-trace now, which will
557 execute all events serialized to get a chance to catch a possible
558 action that crashes the box.
560 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
561 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
562 are excluded from the warning. Referencing parent attributes directly
563 may break when something in the kernel driver model changes. Udev will
564 just find the attribute by walking up the parent chain.
566 Udevtrigger now sorts the list of devices depending on the device
567 dependency, so a "usb" device is triggered after the parent "pci"
572 Revert persistent-storage ata-serial '_' '-' replacement.
578 Udevtrigger can now filter the list of devices to be triggered. Matches
579 for subsystems or sysfs attributes can be specified.
581 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
582 zero-sized files to avoid pointing to /sys and confuse broken tools which
583 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
586 The rules and scripts to create udev rules for persistent network
587 devices and optical drives are in the extras/rules_generator directory
588 now. If you use something similar, please consider replacing your own
589 version with this, to share the support effort. The rule_generator
590 installs its own rules into /etc/udev/rules.d.
592 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
593 the rule_generator depends on cdrom_id to be called in an earlier rule.
599 Renaming of some key names (the old names still work):
600 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
601 (The behavior of the key DRIVER will change soon in one of the next
602 releases, to match only the event device, please switch to DRIVERS
603 instead. If DRIVER is used, it will behave like DRIVERS, but an error
605 With the new key names, we have a more consistent and simpler scheme.
606 We can match the properties of the event device only, with: KERNEL,
607 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
608 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
609 longer mentioned in the man page and should be switched in the rule
612 ATTR{file}="value" can be used now, to write to a sysfs file of the
613 event device. Instead of:
614 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
616 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
618 All the PHYSDEV* keys are deprecated and will be removed from a
620 PHYDEVPATH - is the path of a parent device and should not be
622 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
623 matched with SUBSYSTEMS==
624 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
625 Newer kernels will have DRIVER in the environment,
626 for older kernels udev puts in. Class device will
627 no longer carry this property of a parent and
628 DRIVERS== can be used to match such a parent value.
629 Note that ENV{DRIVER} is only available for a few bus devices, where
630 the driver is already bound at device event time. On coldplug, the
631 events for a lot devices are already bound to a driver, and they will have
632 that value set. But on hotplug, at the time the kernel creates the device,
633 it can't know what driver may claim the device after that, therefore
634 in most cases it will be empty.
636 Failed events should now be re-triggered with:
637 udevtrigger --retry-failed.
638 Please switch to this command, so we keep the details of the /dev/.udev/failed/
639 files private to the udev tools. We may need to switch the current symlink
640 target, cause some obviously broken tools try to scan all files in /dev
641 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
642 million times. This takes ages on slow boxes.
644 The udevinfo attribute walk (-a) now works with giving a device node
645 name (-n) instead of a devpath (-p). The query now always works, also when
646 no database file was created by udev.
648 The built-in /etc/passwd /etc/group parser is removed, we always depend on
649 getpwnam() and getgrnam() now. One of the next releases will depend on
650 fnmatch() and may use getopt_long().
654 Bugfixes and small improvements.
658 Fix path_id for recent kernels.
664 Added support for swapping network interface names, by temporarily
665 renaming the device and wait for the target name to become free.
669 The built-in MODALIAS key and substitution is removed.
673 The binary firmware helper is replaced by the usual simple
674 shell script. Udevsend is removed from the tree.
682 Some more keys require the correct use of '==' and '=' depending
683 on the kind of operation beeing an assignment or a match. Rules
684 with invalid operations are skipped and logged to syslog. Please
685 test with udevtest if the parsing of your rules throws errors and
686 fix possibly broken rules.
690 Provide "udevsettle" to wait for all current udev events to finish.
691 It also watches the current kernel netlink queue by comparing the
692 even sequence number to make sure that there are no current pending
693 events that have not already arrived in the daemon.
697 Fix rule to skip persistent rules for removable IDE devices, which
698 also skipped optical IDE drives.
700 All *_id program are installed in /lib/udev/ by default now.
702 No binary is stripped anymore as this should be done in the
703 packaging process and not at build time.
705 libvolume_id is provided as a shared library now and vol_id is
706 linked against it. Also one of the next HAL versions will require
707 this library, and the HAL build process will also require the
708 header file to be installed. The copy of the same code in HAL will
709 be removed to have only a single copy left on the system.
713 Add persistent links for SCSI tapes. The rules file is renamed
714 to 60-persistent-storage.rules.
716 Create persistent path for usb devices. Can be used for all sorts
717 of devices that can't be distinguished by other properties like
718 multiple identical keyboards and mice connected to the same box.
720 Provide "udevtrigger" program to request events on coldplug. The
721 shell script is much too slow with thousends of devices.
725 Fix persistent disk rules to exclude removable IDE drives.
727 Warn if %e, $modalias or MODALIAS is used.
731 Fix queue export, which wasn't correct for subsequent add/remove
732 events for the same device.
736 Fix cramfs detection on big endian.
738 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
743 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
744 attributes were only checked at the parent device that matched the
745 by BUS requested subsystem. Fix it to also look at the device we
746 received the event for.
748 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
753 Fix a bug where NAME="" would prevent RUN from beeing executed.
755 RUN="/bin/program" does not longer automatically add the subsystem
756 as the first parameter. This is from the days of /sbin/hotplug
757 which is dead now and it's just confusing to need to add a space at
758 the end of the program name to prevent this.
759 If you use rules that need the subsystem as the first parameter,
760 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
761 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
765 The udev man page has moved to udev(7) as it does not describe a command
766 anymore. The programs udev, udevstart and udevsend are no longer installed
767 by default and must be copied manually, if they should be installed or
768 included in a package.
770 Fix a bug where "ignore_device" could run earlier collected RUN keys before
771 the ignore rule was applied.
773 More preparation for future sysfs changes. usb_id and scsi_id no longer
774 depend on a magic order of devices in the /devices chain. Specific devices
775 should be requested by their subsytem.
777 This will always find the scsi parent device without depending on a specific
779 dev = sysfs_device_get(devpath);
780 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
782 The "device" link in the current sysfs layout will be automatically
783 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
784 parent in the devpath. If a device is requested by it's symlink, like all
785 class devices in the new sysfs layout will look like, it gets automatically
786 resolved and substituted with the real devpath and not the symlink path.
789 A similar logic must be applied to _all_ sysfs users, including
790 scripts, that search along parent devices in sysfs. The explicit use of
791 the "device" link must be avoided. With the future sysfs layout all
792 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
793 back to the "class" or the "bus". The layout of the parent devices in
794 /devices is not necessarily expected to be stable across kernel releases and
795 searching for parents by their subsystem should make sysfs users tolerant
796 for changed parent chains.
800 Prepare udev to work with the experimental kernel patch, that moves
801 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
803 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
804 moving the class devices to /sys/devices.
806 Thanks again to Marco for help finding a hopefully nice compromise
807 to make %b simpler and working again.
811 Complete removal of libsysfs, replaced by simple helper functions
812 which are much simpler and a bit faster. The udev daemon operatesentirely
813 on event parameters and does not use sysfs for simple rules anymore.
814 Please report any new bugs/problems, that may be caused by this big
815 change. They will be fixed immediately.
817 The enumeration format character '%e' is deprecated and will be
818 removed sometimes from a future udev version. It never worked correctly
819 outside of udevstart, so we can't use it with the new parallel
820 coldplug. A simple enumeration is as useless as the devfs naming
821 scheme, just get rid of both if you still use it.
823 MODALIAS and $modalias is not needed and will be removed from one of
824 the next udev versions, replace it in all rules with ENV{MODALIAS} or
825 the sysfs "modalias" value.
827 Thanks a lot to Marco for all his help on finding and fixing bugs.
831 Let scsi_id request libata drive serial numbers from page 0x80.
833 Renamed etc/udev/persistent.rules to persistent-disk.rules and
834 added /dev/disk/by-name/* for device mapper device names.
836 Removed %e from the man page. It never worked reliably outside
837 of udevstart and udevstart is no longer recommended to use.
841 Symlinks are now exported to the event environment. Hopefully it's no
842 longer needed to run udevinfo from an event process, like it was
843 mentioned on the hotplug list:
844 UDEV [1134776873.702967] add@/block/sdb
847 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
851 Fix a problem if udevsend is used as the hotplug handler and tries to use
852 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
853 and this kind of problems will hopefully go away soon.
857 All built-in logic to work around bad sysfs timing is removed with this
858 version. The need to wait for sysfs files is almost fixed with a kernel
859 version that doesn't work with this udev version anyway. Until we fix
860 the timing of the "bus" link creation, the former integrated logic should
861 be emulated by a rule placed before all other rules:
862 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
864 The option "udev_db" does no longer exist. All udev state will be in
865 /$udev_root/.udev/ now, there is no longer an option to set this
867 If the init script or something else used this value, just depend on
868 this hardcoded path. But remember _all_content_ of this directory is
869 still private to udev and can change at any time.
871 Default location for rule sripts and helper programs is now: /lib/udev/.
872 Everything that is not useful on the commandline should go into this
873 directory. Some of the helpers in the extras folder are installed there
874 now. The rules need to be changed, to find the helpers there.
876 Also /lib/udev/devices is recommended as a directory where packages or
877 the user can place real device nodes, which get copied over to /dev at
878 every boot. This should replace the various solutions with custom config
881 Udevsend does no longer start the udev daemon. This must be done with
882 the init script that prepares /dev on tmpfs and creates the initial nodes,
883 before starting the daemon.
887 Silent a too verbose error logging for the old hotplug.d/ dev.d/
890 The copy of klibc is removed. A systemwide installed version of klibc
891 should be used to build a klibc udev now.
895 NAME="" will not create any nodes, but execute RUN keys. To completely
896 ignore an event the OPTION "ignore_device" should be used.
898 After removal of the reorder queue, events with a TIMEOUT can be executed
899 without any queuing now.
903 Fixed bug in udevd, if inotify is not available. We depend on netlink
904 uevents now, kernels without that event source will not work with that
905 version of udev anymore.
909 The rule parsing happens now in the daemon once at startup, all udev
910 event processes inherit the already parsed rules from the daemon.
911 It is shipped with SUSE10.0 and reduces heavily the system load at
912 startup. The option to save precompiled rules and let the udev process
913 pick the them up is removed, as it's no longer needed.
915 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
916 device. Libsysfs is changed to "translate" the requested link into the
917 real device path, as it would happen with the hotplug event. Otherwise
918 device removal and the udev database will not work.
920 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
923 A few improvements for vol_id, the filesytem probing code.
927 Fix a stupid typo in extras/run_directory for "make install".
929 scsi_id creates the temporary devnode now in /dev for usage with a
930 non-writable /tmp directory.
932 The uevent kernel socket buffer can carry app. 50.000 events now,
933 let's see who can break this again. :)
935 The upcoming kernel will have a new input driver core integration.
936 Some class devices are now symlinks to the real device. libsysfs
937 needs a fix for this to work correctly. Udevstart of older udev
938 versions will _not_ create these devices!
942 Fix a 'install' target in the Makefile, that prevents EXTRAS from
947 A bunch of mostly trivial bugfixes. From now on no node name or
948 symlink name can contain any character than plain whitelisted ascii
949 characters or validated utf8 byte-streams. This is needed for the
950 /dev/disk/by-label/* links, because we import untrusted data and
951 export it to the filesystem.
955 More bugfixes. If udevd was started from the kernel, we don't
956 have stdin/stdout/stderr, which broke the forked tools in some
961 Bugfix. udevstart event ordering was broken for a long time.
962 The new run_program() uncovered it, because /dev/null was not
963 available while we try to run external programs.
964 Now udevstart should create it before we run anything.
968 Minor bugfixes and some distro rules updates. If you don't have the
969 persistent disk rules in /dev/disk/by-*/* on your distro, just
970 grab it from here. :)
974 We can use socket communication now to pass events from udev to
976 RUN+="socket:/org/freedesktop/hal/udev_event"
977 will pass the whole udev event to the HAL daemon without the need
978 for a forked helper. (See ChangeLog for udevmonitor, as an example)
982 Mostly bugfixes and see ChangeLog.
984 The test for the existence of an environment value should be
986 ENV{KEY}=="*" to ENV{KEY}=="?*"
987 because "*" will not fail anymore, if the key does not exist or
992 Bugfixes and a few tweaks described in the ChangeLog.
996 Mostly a Bugfix release.
998 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
999 timing with custom rules.
1003 We changed the internal rule storage format. Our large rule files took
1004 2 MB of RAM, with the change we are down to 99kB.
1006 If the device-node has been created with default name and no symlink or
1007 options are to remenber, it is not longer stored in the udevdb. HAL will
1008 need to be updated to work correctly with that change.
1010 To overrride optimization flags, OPTFLAGS may be used now.
1018 Major changes happened with this release. The goal is to take over the
1019 complete kernel-event handling and provide a more efficient way to dispatch
1020 kernel events. Replacing most of the current shell script logic and the
1021 kernel forked helper with a netlink-daemon and a rule-based event handling.
1023 o udevd listens to netlink events now. The first valid netlink event
1024 will make udevd ignore any message from udevsend that contains a
1025 SEQNUM, to avoid duplicate events. The forked events can be disabled
1027 echo "" > /proc/sys/kernel/hotplug
1028 For full support, the broken input-subsytem needs to be fixed, not to
1029 bypass the driver core.
1031 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
1032 removed from udev itself and must be emulated by calling small
1033 helper binaries provided in the extras folder:
1034 make EXTRAS=extras/run_directory/
1035 will build udev_run_devd and udev_run_hotplugd, which can be called
1036 from a rule if needed:
1037 RUN+="/sbin/udev_run_hotplugd"
1038 The recommended way to handle this is to convert all the calls from
1039 the directories to explicit udev rules and get completely rid of the
1040 multiplexing. (To catch a ttyUSB event, you now no longer need to
1041 fork and exit 300 tty script instances you are not interested in, it
1042 is just one rule that matches exactly the device.)
1044 o udev handles now _all_ events not just events for class and block
1045 devices, this way it is possible to control the complete event
1046 behavior with udev rules. Especially useful for rules like:
1047 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
1049 o As used in the modalias rule, udev supports now textual
1050 substitution placeholder along with the usual format chars. This
1051 needs to be documented, for now it's only visible in udev_rules_parse.c.
1053 o The rule keys support now more operations. This is documented in the
1054 man page. It is possible to add values to list-keys like the SYMLINK
1055 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
1056 Also "final"-assignments are supported by using KEY:="value", which will
1057 prevent changing the key by any later rule.
1059 o kernel 2.6.12 has the "detached_state" attribute removed from
1060 sysfs, which was used to recognize sysfs population. We switched that
1061 to wait for the "bus" link, which is only available in kernels after 2.6.11.
1062 Running this udev version on older kernels may cause a short delay for
1065 o To provide infrastructure for persistent device naming, the id programs:
1066 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
1067 to export the probed data in environment key format:
1068 pim:~ # /sbin/ata_id --export /dev/hda
1069 ID_MODEL=HTS726060M9AT00
1070 ID_SERIAL=MRH401M4G6UM9B
1071 ID_REVISION=MH4OA6BA
1073 The following rules:
1074 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
1075 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
1078 kay@pim:~> tree /dev/disk
1081 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
1082 | `-- IBM-Memory_Key -> ../../sda
1084 | |-- swap -> ../../hda1
1085 | |-- date -> ../../sda1
1086 | `-- home -> ../../hda3
1088 |-- 2E08712B0870F2E7 -> ../../hda3
1089 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
1090 |-- E845-7A89 -> ../../sda1
1091 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
1093 The IMPORT= operation will import these keys in the environment and make
1094 it available for later PROGRAM= and RUN= executed programs. The keys are
1095 also stored in the udevdb and can be queried from there with one of the
1098 o A few binaries are silently added to the repository, which can be used
1099 to replay kernel events from initramfs instead of using coldplug. udevd
1100 can be instructed now to queue-up events while the stored events from
1101 initramfs are filled into the udevd-queue. This code is still under
1102 development and there is no documentation now besides the code itself.
1103 The additional binaries get compiled, but are not installed by default.
1105 o There is also a temporary fix for a performance problem where too many
1106 events happen in parallel and every event needs to parse the rules.
1107 udev can now read precompiled rules stored on disk. This is likely to be
1108 replaced by a more elegant solution in a future udev version.
1112 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
1113 Fix for libsysfs not to expect this file was added.
1117 All rules are applied now, but only the first matching rule with a NAME-key
1118 will be applied. All later rules with NAME-key are completely ignored. This
1119 way system supplied symlinks or permissions gets applied to user-defined
1123 Please check your rules setup, if you may need to add OPTIONS="last_rule"
1124 to some rules, to keep the old behavior.
1126 The rules are read on "remove"-events too. That makes is possible to match
1127 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
1128 instruct udev to ignore an event (OPTIONS="ignore_device").
1129 The new ACTION-key may be used to let a rule act only at a "remove"-event.
1131 The new RUN-key supports rule-based execution of programs after device-node
1132 handling. This is meant as a general replacement for the dev.d/-directories
1133 to give fine grained control over the execution of programs.
1135 The %s{}-sysfs format char replacement values are searched at any of the
1136 devices in the device chain now, not only at the class-device.
1138 We support log priority levels now. The value udev_log in udev.conf is used
1139 to determine what is printed to syslog. This makes it possible to
1140 run a version with compiled-in debug messages in a production environment
1141 which is sometimes needed to find a bug.
1142 It is still possible to supress the inclusion of _any_ syslog usage with
1143 USE_LOG=false to create the smallest possible binaries if needed.
1144 The configured udev_log value can be overridden with the environment variable
1149 Possible use of a system-wide klibc:
1150 make USE_KLIBC=true KLCC=/usr/bin/klcc all
1151 will link against an external klibc and our own version will be ignored.
1155 We support an unlimited count of symlinks now.
1157 If USE_STATIC=true is passed to a glibc build, we link statically and use
1158 a built-in userdb parser to resolve user and group names.
1160 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
1161 we walk up the chain of physical devices to find a match.
1163 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
1164 easy to skip certain attribute matches without composing rules with weird
1165 character class negations like:
1166 KERNEL="[!s][!c][!d]*"
1167 this can now be replaced with:
1169 The current simple '=' is still supported, and should work as it does today,
1170 but existing rules should be converted if possible, to be better readable.
1172 We have new ENV{}== key now, to match against a maximum of 5 environment
1175 udevstart is its own binary again, because we don't need co carry this araound
1176 with every forked event.
~ianmdlvl / elogind.git / blob