5 /dev/serial/by-{id,path}/ now contains links for ttyUSB devices,
6 which do not depend on the kernel device name. As usual, unique
7 devices - only a single one per product connected, or a real
8 USB serial number in the device - are always found with the same
9 name in the by-id/ directory.
10 Completely Identical devices may overwrite their names in by-id/
11 and can only be found reliably in the by-path/ directory. Devices
12 specified by by-path/ must not change their connection, like the
13 USB port number they are plugged in, to keep their name.
19 Fix for a possible segfault while swapping network interface names in udev
26 The group "video" is part of the default rules now.
30 Bugfix for kernels using SYSFS_DEPRECATED* option and finding parent
31 block devices in some cases. No common distro uses this option anymore,
32 and we do not get enough testing for this and recent udev versions. If
33 this option is not needed to run some old distro with a new kernel,
34 it should be disabled in the kernel config.
36 Bugfix for the $links substitution variable, which may crash if no links
37 are created. This should not happen in usual setups because we always
38 create /dev/{block,char}/ links.
40 The strings of the parsed rules, which are kept in memory, no longer
41 contain duplicate entries, or duplicate tails of strings. This, and the
42 new rules parsing/matching code reduces the total in-memory size of
43 a huge distro rule sets to 0.08 MB, compared to the 1.2MB of udev
46 The export of DEVTYPE=disk/partition got removed from the default
47 rules. This value is available from the kernel. The pnp shell script
48 modprobe hack is removed from the default rules. ACPI devices have _proper_
49 modalias support and take care of the same functionality.
50 Installations which support old kernels, but install current default
51 udev rules may want to add that to the compat rules file.
53 Libvolume_id now always probes for all known filesystems, and does not
54 stop at the first match. Some filesystems are marked as "exclusive probe",
55 and if any other filesytem type matches at the same time, libvolume_id
56 will, by default, not return any probing result. This is intended to prevent
57 mis-detection with conflicting left-over signatures found from earlier
58 file system formats. That way, we no longer depend on the probe-order
59 in case of multiple competing signatures. In some setups the kernel allows
60 to mount a volume with just the old filesystem signature still in place.
61 This may damage the new filesystem and cause data-loss, just by mounting
62 it. Because volume_id can not decide which one the correct signature is,
63 the wrong signatures need to be removed manually from the volume, or the
64 volume needs to be reformatted, to enable filesystem detection and possible
69 Fix segfault if compiled without optimization and dbg() does not get
70 compiled out and uses variables which are not available.
74 Bugfixes. (And maybe new bugs. :))
76 The rule matching engine got converted from a rule list to a token
77 array which reduced the in-memory rules representation of a full
78 featured distros with thousends of udev rules from 1.2MB to 0.12 MB.
79 Limits like 5 ENV and ATTR matches, and one single instance for most
80 other keys per rule are gone.
82 The NAME assignment is no longer special cased. If later rules assign
83 a NAME value again, the former value will be overwritten. As usual
84 for most other keys, the NAME value can be protected by doing a final
85 assignment with NAME:="<value>".
87 All udev code now uses libudev, which is also exported. The library
88 is still under development, marked as experimental, and its interface
89 may change as long as the DeviceKit integration is not finished.
91 Many thanks to Alan Jenkins for his continuous help, and finding and
92 optimizing some of the computing expensive parts.
98 Kernel devices and device nodes are connected now by reverse indizes in
99 /sys and /dev. A device number retrieved by a stat() or similar, the
100 kernel device directory can be found by looking up:
101 /sys/dev/{block,char}/<maj>:<min>
102 and the device node of the same device by looking up:
103 /dev/{block,char}/<maj>:<min>
107 Fix recently introduced bug, which caused a compilation without large
108 file support, where vol_id does not recognize raid signatures at the end
111 Firewire disks now create both, by-id/scsi-* and by-id/ieee-* links.
112 Seems some kernel versions prevent the creation of the ieee-* links,
113 so people used the scsi-* link which disappeared now.
115 More libudev work. Almost all udevadm functionality comes from libudev
118 udevadm trigger has a new option --type, which allows to trigger events
119 for "devices", for "subsystems", or "failed" devices. The old option
120 --retry-failed" still works, but is no longer mentioned in the man page.
126 The udevadm info --device-id-of-file= output has changed to use
127 the obvious format. Possible current users should use the --export
128 option which is not affected.
130 The old udev commands symlinks to udevadm are not installed, if
131 these symlinks are used, a warning is printed.
137 Optical drive's media is no longer probed for raid signatures,
138 reading the end of the device causes some devices to malfunction.
139 Also the offset of the last session found is used now to probe
142 The volume_id library got a major version number update to 1,
143 some deprecated functions are removed.
145 A shared library "libudev" gets installed now to provide access
146 to udev device information. DeviceKit, the successor of HAL, will
147 need this library to access the udev database and search sysfs for
149 The library is currently in an experimental state, also the API is
150 expected to change, as long as the DeviceKit integration is not
155 We use ./configure now. See INSTALL for details. Current
158 "/usr" - prefix for man pages, include files
160 "" - the root filesystem, prefix for libs and binaries
164 "lib" - directory name for libraries, not a path name
165 multilib 64bit systems may use "lib64" instead of "lib"
167 compile-in verbose debug messages
169 disable all logging and compile-out all log strings
171 link against SELInux libraries, to set the expected context
174 In the default rules, the group "disk" gets permissions 0660 instead
175 of 0640. One small step closer to unify distro rules. Some day, all
176 distros hopefully end up with the same set of rules.
178 No symlinks to udevadm are installed anymore, if they are still needed,
179 they should be provided by the package.
185 Default udev rules, which are not supposed to be edited by the user, should
186 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
187 the udev package and will be replaced with an update. Udev will pick up rule
189 /lib/udev/rules.d/ - default installed rules
190 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
191 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
192 It does not matter in which directory a rule file lives, all files are sorted
195 To help creating /dev/root, we have now:
196 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
199 In case the current --device-id-of-file is already used, please switch to
200 the --export format version, it saves the output parsing and the old
201 format will be changed to use ':' as a separator, like the format in the
206 Fix cdrom_id to properly recognize blank media.
212 Tape drive id-data is queried from /dev/bsg/* instead of the tape
213 nodes. This avoids rewinding tapes on open().
219 The symlinks udevcontrol and udevtrigger are no longer installed by
222 The scsi_id program does not depend on sysfs anymore. It can speak
223 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
224 data, which should solve some old problems with tape devices, where
225 we better do not open all tape device nodes to identify the device.
231 The cdrom_id program is replaced by an advanced version, which can
232 detect most common device types, and also properties of the inserted
233 media. This is part of moving some basic functionality from HAL into
234 udev (and the kernel).
240 The last WAIT_FOR_SYSFS rule is removed from the default rules.
242 The symlinks to udevadm for the debugging tools: udevmonitor and
243 udevtest are no longer created.
245 The symlinks to the udevadm man page for the old tool names are
248 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
249 should be prefixed with '@' to indicate that the path is not a
260 Udevstart is removed from the tree, it did not get installed for
261 a long time now, and is long replaced by trigger and settle.
267 All udev tools are merged into a single binary called udevadm.
268 The old names of the tools are built-in commands in udevadm now.
269 Symlinks to udevadm, with the names of the old tools, provide
270 the same functionality as the standalone tools. There is also
271 only a single udevadm.8 man page left for all tools.
273 Tools like mkinitramfs should be checked, if they need to include
274 udevadm in the list of files.
284 The etc/udev/rules.d/ directory now contains a default set of basic
285 udev rules. This initial version is the result of a rules file merge
286 of Fedora and openSUSE. For these both distros only a few specific
287 rules are left in their own file, named after the distro. Rules which
288 are optionally installed, because they are only valid for a specific
289 architecture, or rules for subsystems which are not always used are
290 in etc/udev/packages/.
296 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
297 actions by dynamically created rules.
299 SYMLINK=="<value>" matches agains the entries in the list of
300 currently defined symlinks. The links are not created in the
301 filesystem at that point in time, but the values can be matched.
303 RUN{ignore_error}+="<program>" will ignore any exit code from the
304 program and not record as a failed event.
310 Final merge of patches/features from the Ubuntu package.
316 Control characters in filesystem label strings are no longer silenty
317 removed, but hex-encoded, to be able to uniquely identify the device
318 by its symlink in /dev/disk/by-label/.
319 If libvolume_id is used by mount(8), LABEL= will work as expected,
320 if slashes or other characters are used in the label string.
322 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
323 can be specified now. The TEST key accepts an optional mode mask
324 TEST{0100}=="<is executable file>".
326 Scsi_id now supports a mode without expecting scsi-specific sysfs
327 entries to allow the extraction of cciss-device persistent properties.
333 In the future, we may see uuid's which are just simple character
334 strings (see the DDF Raid Specification). For that reason vol_id now
335 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
336 the creation of symlinks, the *_SAFE values ensure, that no control
337 or whitespace characters are used in the filename.
339 Possible users of libvolume_id, please use the volume_id_get_* functions.
340 The public struct will go away in a future release of the library.
346 Removal of useless extras/eventrecorder.sh.
356 The directory multiplexer for dev.d/ and hotplug.d are finally removed
357 from the udev package.
363 Symlinks can have priorities now, the priority is assigned to the device
364 and specified with OPTIONS="link_priority=100". Devices with higher
365 priorities overwrite the symlinks of devices with lower priorities.
366 If the device that currently owns the link, goes away, the symlink
367 will be removed, and recreated, pointing to the next device with the
368 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
369 more reliable, if multiple devices contain the same metadata and overwrite
372 The dasd_id program is removed from the udev tree, and dasdinfo, with the
373 needed rules, are part of the s390-tools now.
375 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
376 we may get the scsi sysfs mess fixed some day, and this will only catch
377 the devices we are looking for.
379 USB serial numbers for storage devices have the target:lun now appended,
380 to make it possibble to distinguish broken multi-lun devices with all
381 the same SCSI identifiers.
383 Note: The extra "run_directory" which searches and executes stuff in
384 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
385 with the next release. Make sure, that you don't use it anymore, or
386 provides your own implementation of that inefficient stuff.
387 We are tired of reports about a "slow udev", because these directories
388 contain stuff, that runs with _every_ event, instead of using rules,
389 that run programs only for the matching events.
399 DRIVER== will match only for devices that actually have a real
400 driver. DRIVERS== must be used, if parent devices should be
401 included in the match.
403 Libvolume_id's "linux_raid" detection needed another fix.
411 Add additional check to volume_id detection of via_raid, cause
412 some company decided to put a matching pattern all over the empty
413 storage area of their music players.
417 Fix path_id for SAS devices.
421 The udev daemon can be started with --debug-trace now, which will
422 execute all events serialized to get a chance to catch a possible
423 action that crashes the box.
425 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
426 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
427 are excluded from the warning. Referencing parent attributes directly
428 may break when something in the kernel driver model changes. Udev will
429 just find the attribute by walking up the parent chain.
431 Udevtrigger now sorts the list of devices depending on the device
432 dependency, so a "usb" device is triggered after the parent "pci"
437 Revert persistent-storage ata-serial '_' '-' replacement.
443 Udevtrigger can now filter the list of devices to be triggered. Matches
444 for subsystems or sysfs attributes can be specified.
446 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
447 zero-sized files to avoid pointing to /sys and confuse broken tools which
448 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
451 The rules and scripts to create udev rules for persistent network
452 devices and optical drives are in the extras/rules_generator directory
453 now. If you use something similar, please consider replacing your own
454 version with this, to share the support effort. The rule_generator
455 installs its own rules into /etc/udev/rules.d.
457 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
458 the rule_generator depends on cdrom_id to be called in an earlier rule.
464 Renaming of some key names (the old names still work):
465 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
466 (The behavior of the key DRIVER will change soon in one of the next
467 releases, to match only the event device, please switch to DRIVERS
468 instead. If DRIVER is used, it will behave like DRIVERS, but an error
470 With the new key names, we have a more consistent and simpler scheme.
471 We can match the properties of the event device only, with: KERNEL,
472 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
473 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
474 longer mentioned in the man page and should be switched in the rule
477 ATTR{file}="value" can be used now, to write to a sysfs file of the
478 event device. Instead of:
479 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
481 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
483 All the PHYSDEV* keys are deprecated and will be removed from a
485 PHYDEVPATH - is the path of a parent device and should not be
487 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
488 matched with SUBSYSTEMS==
489 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
490 Newer kernels will have DRIVER in the environment,
491 for older kernels udev puts in. Class device will
492 no longer carry this property of a parent and
493 DRIVERS== can be used to match such a parent value.
494 Note that ENV{DRIVER} is only available for a few bus devices, where
495 the driver is already bound at device event time. On coldplug, the
496 events for a lot devices are already bound to a driver, and they will have
497 that value set. But on hotplug, at the time the kernel creates the device,
498 it can't know what driver may claim the device after that, therefore
499 in most cases it will be empty.
501 Failed events should now be re-triggered with:
502 udevtrigger --retry-failed.
503 Please switch to this command, so we keep the details of the /dev/.udev/failed/
504 files private to the udev tools. We may need to switch the current symlink
505 target, cause some obviously broken tools try to scan all files in /dev
506 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
507 million times. This takes ages on slow boxes.
509 The udevinfo attribute walk (-a) now works with giving a device node
510 name (-n) instead of a devpath (-p). The query now always works, also when
511 no database file was created by udev.
513 The built-in /etc/passwd /etc/group parser is removed, we always depend on
514 getpwnam() and getgrnam() now. One of the next releases will depend on
515 fnmatch() and may use getopt_long().
519 Bugfixes and small improvements.
523 Fix path_id for recent kernels.
529 Added support for swapping network interface names, by temporarily
530 renaming the device and wait for the target name to become free.
534 The built-in MODALIAS key and substitution is removed.
538 The binary firmware helper is replaced by the usual simple
539 shell script. Udevsend is removed from the tree.
547 Some more keys require the correct use of '==' and '=' depending
548 on the kind of operation beeing an assignment or a match. Rules
549 with invalid operations are skipped and logged to syslog. Please
550 test with udevtest if the parsing of your rules throws errors and
551 fix possibly broken rules.
555 Provide "udevsettle" to wait for all current udev events to finish.
556 It also watches the current kernel netlink queue by comparing the
557 even sequence number to make sure that there are no current pending
558 events that have not already arrived in the daemon.
562 Fix rule to skip persistent rules for removable IDE devices, which
563 also skipped optical IDE drives.
565 All *_id program are installed in /lib/udev/ by default now.
567 No binary is stripped anymore as this should be done in the
568 packaging process and not at build time.
570 libvolume_id is provided as a shared library now and vol_id is
571 linked against it. Also one of the next HAL versions will require
572 this library, and the HAL build process will also require the
573 header file to be installed. The copy of the same code in HAL will
574 be removed to have only a single copy left on the system.
578 Add persistent links for SCSI tapes. The rules file is renamed
579 to 60-persistent-storage.rules.
581 Create persistent path for usb devices. Can be used for all sorts
582 of devices that can't be distinguished by other properties like
583 multiple identical keyboards and mice connected to the same box.
585 Provide "udevtrigger" program to request events on coldplug. The
586 shell script is much too slow with thousends of devices.
590 Fix persistent disk rules to exclude removable IDE drives.
592 Warn if %e, $modalias or MODALIAS is used.
596 Fix queue export, which wasn't correct for subsequent add/remove
597 events for the same device.
601 Fix cramfs detection on big endian.
603 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
608 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
609 attributes were only checked at the parent device that matched the
610 by BUS requested subsystem. Fix it to also look at the device we
611 received the event for.
613 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
618 Fix a bug where NAME="" would prevent RUN from beeing executed.
620 RUN="/bin/program" does not longer automatically add the subsystem
621 as the first parameter. This is from the days of /sbin/hotplug
622 which is dead now and it's just confusing to need to add a space at
623 the end of the program name to prevent this.
624 If you use rules that need the subsystem as the first parameter,
625 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
626 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
630 The udev man page has moved to udev(7) as it does not describe a command
631 anymore. The programs udev, udevstart and udevsend are no longer installed
632 by default and must be copied manually, if they should be installed or
633 included in a package.
635 Fix a bug where "ignore_device" could run earlier collected RUN keys before
636 the ignore rule was applied.
638 More preparation for future sysfs changes. usb_id and scsi_id no longer
639 depend on a magic order of devices in the /devices chain. Specific devices
640 should be requested by their subsytem.
642 This will always find the scsi parent device without depending on a specific
644 dev = sysfs_device_get(devpath);
645 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
647 The "device" link in the current sysfs layout will be automatically
648 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
649 parent in the devpath. If a device is requested by it's symlink, like all
650 class devices in the new sysfs layout will look like, it gets automatically
651 resolved and substituted with the real devpath and not the symlink path.
654 A similar logic must be applied to _all_ sysfs users, including
655 scripts, that search along parent devices in sysfs. The explicit use of
656 the "device" link must be avoided. With the future sysfs layout all
657 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
658 back to the "class" or the "bus". The layout of the parent devices in
659 /devices is not necessarily expected to be stable across kernel releases and
660 searching for parents by their subsystem should make sysfs users tolerant
661 for changed parent chains.
665 Prepare udev to work with the experimental kernel patch, that moves
666 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
668 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
669 moving the class devices to /sys/devices.
671 Thanks again to Marco for help finding a hopefully nice compromise
672 to make %b simpler and working again.
676 Complete removal of libsysfs, replaced by simple helper functions
677 which are much simpler and a bit faster. The udev daemon operatesentirely
678 on event parameters and does not use sysfs for simple rules anymore.
679 Please report any new bugs/problems, that may be caused by this big
680 change. They will be fixed immediately.
682 The enumeration format character '%e' is deprecated and will be
683 removed sometimes from a future udev version. It never worked correctly
684 outside of udevstart, so we can't use it with the new parallel
685 coldplug. A simple enumeration is as useless as the devfs naming
686 scheme, just get rid of both if you still use it.
688 MODALIAS and $modalias is not needed and will be removed from one of
689 the next udev versions, replace it in all rules with ENV{MODALIAS} or
690 the sysfs "modalias" value.
692 Thanks a lot to Marco for all his help on finding and fixing bugs.
696 Let scsi_id request libata drive serial numbers from page 0x80.
698 Renamed etc/udev/persistent.rules to persistent-disk.rules and
699 added /dev/disk/by-name/* for device mapper device names.
701 Removed %e from the man page. It never worked reliably outside
702 of udevstart and udevstart is no longer recommended to use.
706 Symlinks are now exported to the event environment. Hopefully it's no
707 longer needed to run udevinfo from an event process, like it was
708 mentioned on the hotplug list:
709 UDEV [1134776873.702967] add@/block/sdb
712 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
716 Fix a problem if udevsend is used as the hotplug handler and tries to use
717 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
718 and this kind of problems will hopefully go away soon.
722 All built-in logic to work around bad sysfs timing is removed with this
723 version. The need to wait for sysfs files is almost fixed with a kernel
724 version that doesn't work with this udev version anyway. Until we fix
725 the timing of the "bus" link creation, the former integrated logic should
726 be emulated by a rule placed before all other rules:
727 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
729 The option "udev_db" does no longer exist. All udev state will be in
730 /$udev_root/.udev/ now, there is no longer an option to set this
732 If the init script or something else used this value, just depend on
733 this hardcoded path. But remember _all_content_ of this directory is
734 still private to udev and can change at any time.
736 Default location for rule sripts and helper programs is now: /lib/udev/.
737 Everything that is not useful on the commandline should go into this
738 directory. Some of the helpers in the extras folder are installed there
739 now. The rules need to be changed, to find the helpers there.
741 Also /lib/udev/devices is recommended as a directory where packages or
742 the user can place real device nodes, which get copied over to /dev at
743 every boot. This should replace the various solutions with custom config
746 Udevsend does no longer start the udev daemon. This must be done with
747 the init script that prepares /dev on tmpfs and creates the initial nodes,
748 before starting the daemon.
752 Silent a too verbose error logging for the old hotplug.d/ dev.d/
755 The copy of klibc is removed. A systemwide installed version of klibc
756 should be used to build a klibc udev now.
760 NAME="" will not create any nodes, but execute RUN keys. To completely
761 ignore an event the OPTION "ignore_device" should be used.
763 After removal of the reorder queue, events with a TIMEOUT can be executed
764 without any queuing now.
768 Fixed bug in udevd, if inotify is not available. We depend on netlink
769 uevents now, kernels without that event source will not work with that
770 version of udev anymore.
774 The rule parsing happens now in the daemon once at startup, all udev
775 event processes inherit the already parsed rules from the daemon.
776 It is shipped with SUSE10.0 and reduces heavily the system load at
777 startup. The option to save precompiled rules and let the udev process
778 pick the them up is removed, as it's no longer needed.
780 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
781 device. Libsysfs is changed to "translate" the requested link into the
782 real device path, as it would happen with the hotplug event. Otherwise
783 device removal and the udev database will not work.
785 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
788 A few improvements for vol_id, the filesytem probing code.
792 Fix a stupid typo in extras/run_directory for "make install".
794 scsi_id creates the temporary devnode now in /dev for usage with a
795 non-writable /tmp directory.
797 The uevent kernel socket buffer can carry app. 50.000 events now,
798 let's see who can break this again. :)
800 The upcoming kernel will have a new input driver core integration.
801 Some class devices are now symlinks to the real device. libsysfs
802 needs a fix for this to work correctly. Udevstart of older udev
803 versions will _not_ create these devices!
807 Fix a 'install' target in the Makefile, that prevents EXTRAS from
812 A bunch of mostly trivial bugfixes. From now on no node name or
813 symlink name can contain any character than plain whitelisted ascii
814 characters or validated utf8 byte-streams. This is needed for the
815 /dev/disk/by-label/* links, because we import untrusted data and
816 export it to the filesystem.
820 More bugfixes. If udevd was started from the kernel, we don't
821 have stdin/stdout/stderr, which broke the forked tools in some
826 Bugfix. udevstart event ordering was broken for a long time.
827 The new run_program() uncovered it, because /dev/null was not
828 available while we try to run external programs.
829 Now udevstart should create it before we run anything.
833 Minor bugfixes and some distro rules updates. If you don't have the
834 persistent disk rules in /dev/disk/by-*/* on your distro, just
835 grab it from here. :)
839 We can use socket communication now to pass events from udev to
841 RUN+="socket:/org/freedesktop/hal/udev_event"
842 will pass the whole udev event to the HAL daemon without the need
843 for a forked helper. (See ChangeLog for udevmonitor, as an example)
847 Mostly bugfixes and see ChangeLog.
849 The test for the existence of an environment value should be
851 ENV{KEY}=="*" to ENV{KEY}=="?*"
852 because "*" will not fail anymore, if the key does not exist or
857 Bugfixes and a few tweaks described in the ChangeLog.
861 Mostly a Bugfix release.
863 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
864 timing with custom rules.
868 We changed the internal rule storage format. Our large rule files took
869 2 MB of RAM, with the change we are down to 99kB.
871 If the device-node has been created with default name and no symlink or
872 options are to remenber, it is not longer stored in the udevdb. HAL will
873 need to be updated to work correctly with that change.
875 To overrride optimization flags, OPTFLAGS may be used now.
883 Major changes happened with this release. The goal is to take over the
884 complete kernel-event handling and provide a more efficient way to dispatch
885 kernel events. Replacing most of the current shell script logic and the
886 kernel forked helper with a netlink-daemon and a rule-based event handling.
888 o udevd listens to netlink events now. The first valid netlink event
889 will make udevd ignore any message from udevsend that contains a
890 SEQNUM, to avoid duplicate events. The forked events can be disabled
892 echo "" > /proc/sys/kernel/hotplug
893 For full support, the broken input-subsytem needs to be fixed, not to
894 bypass the driver core.
896 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
897 removed from udev itself and must be emulated by calling small
898 helper binaries provided in the extras folder:
899 make EXTRAS=extras/run_directory/
900 will build udev_run_devd and udev_run_hotplugd, which can be called
901 from a rule if needed:
902 RUN+="/sbin/udev_run_hotplugd"
903 The recommended way to handle this is to convert all the calls from
904 the directories to explicit udev rules and get completely rid of the
905 multiplexing. (To catch a ttyUSB event, you now no longer need to
906 fork and exit 300 tty script instances you are not interested in, it
907 is just one rule that matches exactly the device.)
909 o udev handles now _all_ events not just events for class and block
910 devices, this way it is possible to control the complete event
911 behavior with udev rules. Especially useful for rules like:
912 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
914 o As used in the modalias rule, udev supports now textual
915 substitution placeholder along with the usual format chars. This
916 needs to be documented, for now it's only visible in udev_rules_parse.c.
918 o The rule keys support now more operations. This is documented in the
919 man page. It is possible to add values to list-keys like the SYMLINK
920 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
921 Also "final"-assignments are supported by using KEY:="value", which will
922 prevent changing the key by any later rule.
924 o kernel 2.6.12 has the "detached_state" attribute removed from
925 sysfs, which was used to recognize sysfs population. We switched that
926 to wait for the "bus" link, which is only available in kernels after 2.6.11.
927 Running this udev version on older kernels may cause a short delay for
930 o To provide infrastructure for persistent device naming, the id programs:
931 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
932 to export the probed data in environment key format:
933 pim:~ # /sbin/ata_id --export /dev/hda
934 ID_MODEL=HTS726060M9AT00
935 ID_SERIAL=MRH401M4G6UM9B
939 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
940 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
943 kay@pim:~> tree /dev/disk
946 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
947 | `-- IBM-Memory_Key -> ../../sda
949 | |-- swap -> ../../hda1
950 | |-- date -> ../../sda1
951 | `-- home -> ../../hda3
953 |-- 2E08712B0870F2E7 -> ../../hda3
954 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
955 |-- E845-7A89 -> ../../sda1
956 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
958 The IMPORT= operation will import these keys in the environment and make
959 it available for later PROGRAM= and RUN= executed programs. The keys are
960 also stored in the udevdb and can be queried from there with one of the
963 o A few binaries are silently added to the repository, which can be used
964 to replay kernel events from initramfs instead of using coldplug. udevd
965 can be instructed now to queue-up events while the stored events from
966 initramfs are filled into the udevd-queue. This code is still under
967 development and there is no documentation now besides the code itself.
968 The additional binaries get compiled, but are not installed by default.
970 o There is also a temporary fix for a performance problem where too many
971 events happen in parallel and every event needs to parse the rules.
972 udev can now read precompiled rules stored on disk. This is likely to be
973 replaced by a more elegant solution in a future udev version.
977 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
978 Fix for libsysfs not to expect this file was added.
982 All rules are applied now, but only the first matching rule with a NAME-key
983 will be applied. All later rules with NAME-key are completely ignored. This
984 way system supplied symlinks or permissions gets applied to user-defined
988 Please check your rules setup, if you may need to add OPTIONS="last_rule"
989 to some rules, to keep the old behavior.
991 The rules are read on "remove"-events too. That makes is possible to match
992 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
993 instruct udev to ignore an event (OPTIONS="ignore_device").
994 The new ACTION-key may be used to let a rule act only at a "remove"-event.
996 The new RUN-key supports rule-based execution of programs after device-node
997 handling. This is meant as a general replacement for the dev.d/-directories
998 to give fine grained control over the execution of programs.
1000 The %s{}-sysfs format char replacement values are searched at any of the
1001 devices in the device chain now, not only at the class-device.
1003 We support log priority levels now. The value udev_log in udev.conf is used
1004 to determine what is printed to syslog. This makes it possible to
1005 run a version with compiled-in debug messages in a production environment
1006 which is sometimes needed to find a bug.
1007 It is still possible to supress the inclusion of _any_ syslog usage with
1008 USE_LOG=false to create the smallest possible binaries if needed.
1009 The configured udev_log value can be overridden with the environment variable
1014 Possible use of a system-wide klibc:
1015 make USE_KLIBC=true KLCC=/usr/bin/klcc all
1016 will link against an external klibc and our own version will be ignored.
1020 We support an unlimited count of symlinks now.
1022 If USE_STATIC=true is passed to a glibc build, we link statically and use
1023 a built-in userdb parser to resolve user and group names.
1025 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
1026 we walk up the chain of physical devices to find a match.
1028 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
1029 easy to skip certain attribute matches without composing rules with weird
1030 character class negations like:
1031 KERNEL="[!s][!c][!d]*"
1032 this can now be replaced with:
1034 The current simple '=' is still supported, and should work as it does today,
1035 but existing rules should be converted if possible, to be better readable.
1037 We have new ENV{}== key now, to match against a maximum of 5 environment
1040 udevstart is its own binary again, because we don't need co carry this araound
1041 with every forked event.
~ianmdlvl / elogind.git / blob