3 The udev daemon can be started with --debug-trace now, which will
4 execute all events serialized to get a chance to catch a possible
5 action that crashes the box.
7 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
8 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
9 are excluded from the warning. Referencing parent attributes directly
10 may break when something in the kernel driver model changes. Udev will
11 just find the attribute by walking up the parent chain.
13 Udevtrigger now sorts the list of devices depending on the device
14 dependency, so a "usb" device is triggered after the parent "pci"
19 Revert persistent-storage ata-serial '_' '-' replacement.
25 Udevtrigger can now filter the list of devices to be triggered. Matches
26 for subsystems or sysfs attributes can be specified.
28 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
29 zero-sized files to avoid pointing to /sys and confuse broken tools which
30 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
33 The rules and scripts to create udev rules for persistent network
34 devices and optical drives are in the extras/rules_generator directory
35 now. If you use something similar, please consider replacing your own
36 version with this, to share the support effort. The rule_generator
37 installs its own rules into /etc/udev/rules.d.
39 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
40 the rule_generator depends on cdrom_id to be called in an earlier rule.
46 Renaming of some key names (the old names still work):
47 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
48 (The behavior of the key DRIVER will change soon in one of the next
49 releases, to match only the event device, please switch to DRIVERS
50 instead. If DRIVER is used, it will behave like DRIVERS, but an error
52 With the new key names, we have a more consistent and simpler scheme.
53 We can match the properties of the event device only, with: KERNEL,
54 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
55 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
56 longer mentioned in the man page and should be switched in the rule
59 ATTR{file}="value" can be used now, to write to a sysfs file of the
60 event device. Instead of:
61 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
63 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
65 All the PHYSDEV* keys are deprecated and will be removed from a
67 PHYDEVPATH - is the path of a parent device and should not be
69 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
70 matched with SUBSYSTEMS==
71 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
72 Newer kernels will have DRIVER in the environment,
73 for older kernels udev puts in. Class device will
74 no longer carry this property of a parent and
75 DRIVERS== can be used to match such a parent value.
76 Note that ENV{DRIVER} is only available for a few bus devices, where
77 the driver is already bound at device event time. On coldplug, the
78 events for a lot devices are already bound to a driver, and they will have
79 that value set. But on hotplug, at the time the kernel creates the device,
80 it can't know what driver may claim the device after that, therefore
81 in most cases it will be empty.
83 Failed events should now be re-triggered with:
84 udevtrigger --retry-failed.
85 Please switch to this command, so we keep the details of the /dev/.udev/failed/
86 files private to the udev tools. We may need to switch the current symlink
87 target, cause some obviously broken tools try to scan all files in /dev
88 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
89 million times. This takes ages on slow boxes.
91 The udevinfo attribute walk (-a) now works with giving a device node
92 name (-n) instead of a devpath (-p). The query now always works, also when
93 no database file was created by udev.
95 The built-in /etc/passwd /etc/group parser is removed, we always depend on
96 getpwnam() and getgrnam() now. One of the next releases will depend on
97 fnmatch() and may use getopt_long().
101 Bugfixes and small improvements.
105 Fix path_id for recent kernels.
111 Added support for swapping network interface names, by temporarily
112 renaming the device and wait for the target name to become free.
116 The built-in MODALIAS key and substitution is removed.
120 The binary firmware helper is replaced by the usual simple
121 shell script. Udevsend is removed from the tree.
129 Some more keys require the correct use of '==' and '=' depending
130 on the kind of operation beeing an assignment or a match. Rules
131 with invalid operations are skipped and logged to syslog. Please
132 test with udevtest if the parsing of your rules throws errors and
133 fix possibly broken rules.
137 Provide "udevsettle" to wait for all current udev events to finish.
138 It also watches the current kernel netlink queue by comparing the
139 even sequence number to make sure that there are no current pending
140 events that have not already arrived in the daemon.
144 Fix rule to skip persistent rules for removable IDE devices, which
145 also skipped optical IDE drives.
147 All *_id program are installed in /lib/udev/ by default now.
149 No binary is stripped anymore as this should be done in the
150 packaging process and not at build time.
152 libvolume_id is provided as a shared library now and vol_id is
153 linked against it. Also one of the next HAL versions will require
154 this library, and the HAL build process will also require the
155 header file to be installed. The copy of the same code in HAL will
156 be removed to have only a single copy left on the system.
160 Add persistent links for SCSI tapes. The rules file is renamed
161 to 60-persistent-storage.rules.
163 Create persistent path for usb devices. Can be used for all sorts
164 of devices that can't be distinguished by other properties like
165 multiple identical keyboards and mice connected to the same box.
167 Provide "udevtrigger" program to request events on coldplug. The
168 shell script is much too slow with thousends of devices.
172 Fix persistent disk rules to exclude removable IDE drives.
174 Warn if %e, $modalias or MODALIAS is used.
178 Fix queue export, which wasn't correct for subsequent add/remove
179 events for the same device.
183 Fix cramfs detection on big endian.
185 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
190 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
191 attributes were only checked at the parent device that matched the
192 by BUS requested subsystem. Fix it to also look at the device we
193 received the event for.
195 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
200 Fix a bug where NAME="" would prevent RUN from beeing executed.
202 RUN="/bin/program" does not longer automatically add the subsystem
203 as the first parameter. This is from the days of /sbin/hotplug
204 which is dead now and it's just confusing to need to add a space at
205 the end of the program name to prevent this.
206 If you use rules that need the subsystem as the first parameter,
207 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
208 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
212 The udev man page has moved to udev(7) as it does not describe a command
213 anymore. The programs udev, udevstart and udevsend are no longer installed
214 by default and must be copied manually, if they should be installed or
215 included in a package.
217 Fix a bug where "ignore_device" could run earlier collected RUN keys before
218 the ignore rule was applied.
220 More preparation for future sysfs changes. usb_id and scsi_id no longer
221 depend on a magic order of devices in the /devices chain. Specific devices
222 should be requested by their subsytem.
224 This will always find the scsi parent device without depending on a specific
226 dev = sysfs_device_get(devpath);
227 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
229 The "device" link in the current sysfs layout will be automatically
230 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
231 parent in the devpath. If a device is requested by it's symlink, like all
232 class devices in the new sysfs layout will look like, it gets automatically
233 resolved and substituted with the real devpath and not the symlink path.
236 A similar logic must be applied to _all_ sysfs users, including
237 scripts, that search along parent devices in sysfs. The explicit use of
238 the "device" link must be avoided. With the future sysfs layout all
239 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
240 back to the "class" or the "bus". The layout of the parent devices in
241 /devices is not necessarily expected to be stable across kernel releases and
242 searching for parents by their subsystem should make sysfs users tolerant
243 for changed parent chains.
247 Prepare udev to work with the experimental kernel patch, that moves
248 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
250 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
251 moving the class devices to /sys/devices.
253 Thanks again to Marco for help finding a hopefully nice compromise
254 to make %b simpler and working again.
258 Complete removal of libsysfs, replaced by simple helper functions
259 which are much simpler and a bit faster. The udev daemon operatesentirely
260 on event parameters and does not use sysfs for simple rules anymore.
261 Please report any new bugs/problems, that may be caused by this big
262 change. They will be fixed immediately.
264 The enumeration format character '%e' is deprecated and will be
265 removed sometimes from a future udev version. It never worked correctly
266 outside of udevstart, so we can't use it with the new parallel
267 coldplug. A simple enumeration is as useless as the devfs naming
268 scheme, just get rid of both if you still use it.
270 MODALIAS and $modalias is not needed and will be removed from one of
271 the next udev versions, replace it in all rules with ENV{MODALIAS} or
272 the sysfs "modalias" value.
274 Thanks a lot to Marco for all his help on finding and fixing bugs.
278 Let scsi_id request libata drive serial numbers from page 0x80.
280 Renamed etc/udev/persistent.rules to persistent-disk.rules and
281 added /dev/disk/by-name/* for device mapper device names.
283 Removed %e from the man page. It never worked reliably outside
284 of udevstart and udevstart is no longer recommended to use.
288 Symlinks are now exported to the event environment. Hopefully it's no
289 longer needed to run udevinfo from an event process, like it was
290 mentioned on the hotplug list:
291 UDEV [1134776873.702967] add@/block/sdb
294 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
298 Fix a problem if udevsend is used as the hotplug handler and tries to use
299 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
300 and this kind of problems will hopefully go away soon.
304 All built-in logic to work around bad sysfs timing is removed with this
305 version. The need to wait for sysfs files is almost fixed with a kernel
306 version that doesn't work with this udev version anyway. Until we fix
307 the timing of the "bus" link creation, the former integrated logic should
308 be emulated by a rule placed before all other rules:
309 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
311 The option "udev_db" does no longer exist. All udev state will be in
312 /$udev_root/.udev/ now, there is no longer an option to set this
314 If the init script or something else used this value, just depend on
315 this hardcoded path. But remember _all_content_ of this directory is
316 still private to udev and can change at any time.
318 Default location for rule sripts and helper programs is now: /lib/udev/.
319 Everything that is not useful on the commandline should go into this
320 directory. Some of the helpers in the extras folder are installed there
321 now. The rules need to be changed, to find the helpers there.
323 Also /lib/udev/devices is recommended as a directory where packages or
324 the user can place real device nodes, which get copied over to /dev at
325 every boot. This should replace the various solutions with custom config
328 Udevsend does no longer start the udev daemon. This must be done with
329 the init script that prepares /dev on tmpfs and creates the initial nodes,
330 before starting the daemon.
334 Silent a too verbose error logging for the old hotplug.d/ dev.d/
337 The copy of klibc is removed. A systemwide installed version of klibc
338 should be used to build a klibc udev now.
342 NAME="" will not create any nodes, but execute RUN keys. To completely
343 ignore an event the OPTION "ignore_device" should be used.
345 After removal of the reorder queue, events with a TIMEOUT can be executed
346 without any queuing now.
350 Fixed bug in udevd, if inotify is not available. We depend on netlink
351 uevents now, kernels without that event source will not work with that
352 version of udev anymore.
356 The rule parsing happens now in the daemon once at startup, all udev
357 event processes inherit the already parsed rules from the daemon.
358 It is shipped with SUSE10.0 and reduces heavily the system load at
359 startup. The option to save precompiled rules and let the udev process
360 pick the them up is removed, as it's no longer needed.
362 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
363 device. Libsysfs is changed to "translate" the requested link into the
364 real device path, as it would happen with the hotplug event. Otherwise
365 device removal and the udev database will not work.
367 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
370 A few improvements for vol_id, the filesytem probing code.
374 Fix a stupid typo in extras/run_directory for "make install".
376 scsi_id creates the temporary devnode now in /dev for usage with a
377 non-writable /tmp directory.
379 The uevent kernel socket buffer can carry app. 50.000 events now,
380 let's see who can break this again. :)
382 The upcoming kernel will have a new input driver core integration.
383 Some class devices are now symlinks to the real device. libsysfs
384 needs a fix for this to work correctly. Udevstart of older udev
385 versions will _not_ create these devices!
389 Fix a 'install' target in the Makefile, that prevents EXTRAS from
394 A bunch of mostly trivial bugfixes. From now on no node name or
395 symlink name can contain any character than plain whitelisted ascii
396 characters or validated utf8 byte-streams. This is needed for the
397 /dev/disk/by-label/* links, because we import untrusted data and
398 export it to the filesystem.
402 More bugfixes. If udevd was started from the kernel, we don't
403 have stdin/stdout/stderr, which broke the forked tools in some
408 Bugfix. udevstart event ordering was broken for a long time.
409 The new run_program() uncovered it, because /dev/null was not
410 available while we try to run external programs.
411 Now udevstart should create it before we run anything.
415 Minor bugfixes and some distro rules updates. If you don't have the
416 persistent disk rules in /dev/disk/by-*/* on your distro, just
417 grab it from here. :)
421 We can use socket communication now to pass events from udev to
423 RUN+="socket:/org/freedesktop/hal/udev_event"
424 will pass the whole udev event to the HAL daemon without the need
425 for a forked helper. (See ChangeLog for udevmonitor, as an example)
429 Mostly bugfixes and see ChangeLog.
431 The test for the existence of an environment value should be
433 ENV{KEY}=="*" to ENV{KEY}=="?*"
434 because "*" will not fail anymore, if the key does not exist or
439 Bugfixes and a few tweaks described in the ChangeLog.
443 Mostly a Bugfix release.
445 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
446 timing with custom rules.
450 We changed the internal rule storage format. Our large rule files took
451 2 MB of RAM, with the change we are down to 99kB.
453 If the device-node has been created with default name and no symlink or
454 options are to remenber, it is not longer stored in the udevdb. HAL will
455 need to be updated to work correctly with that change.
457 To overrride optimization flags, OPTFLAGS may be used now.
465 Major changes happened with this release. The goal is to take over the
466 complete kernel-event handling and provide a more efficient way to dispatch
467 kernel events. Replacing most of the current shell script logic and the
468 kernel forked helper with a netlink-daemon and a rule-based event handling.
470 o udevd listens to netlink events now. The first valid netlink event
471 will make udevd ignore any message from udevsend that contains a
472 SEQNUM, to avoid duplicate events. The forked events can be disabled
474 echo "" > /proc/sys/kernel/hotplug
475 For full support, the broken input-subsytem needs to be fixed, not to
476 bypass the driver core.
478 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
479 removed from udev itself and must be emulated by calling small
480 helper binaries provided in the extras folder:
481 make EXTRAS=extras/run_directory/
482 will build udev_run_devd and udev_run_hotplugd, which can be called
483 from a rule if needed:
484 RUN+="/sbin/udev_run_hotplugd"
485 The recommended way to handle this is to convert all the calls from
486 the directories to explicit udev rules and get completely rid of the
487 multiplexing. (To catch a ttyUSB event, you now no longer need to
488 fork and exit 300 tty script instances you are not interested in, it
489 is just one rule that matches exactly the device.)
491 o udev handles now _all_ events not just events for class and block
492 devices, this way it is possible to control the complete event
493 behavior with udev rules. Especially useful for rules like:
494 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
496 o As used in the modalias rule, udev supports now textual
497 substitution placeholder along with the usual format chars. This
498 needs to be documented, for now it's only visible in udev_rules_parse.c.
500 o The rule keys support now more operations. This is documented in the
501 man page. It is possible to add values to list-keys like the SYMLINK
502 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
503 Also "final"-assignments are supported by using KEY:="value", which will
504 prevent changing the key by any later rule.
506 o kernel 2.6.12 has the "detached_state" attribute removed from
507 sysfs, which was used to recognize sysfs population. We switched that
508 to wait for the "bus" link, which is only available in kernels after 2.6.11.
509 Running this udev version on older kernels may cause a short delay for
512 o To provide infrastructure for persistent device naming, the id programs:
513 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
514 to export the probed data in environment key format:
515 pim:~ # /sbin/ata_id --export /dev/hda
516 ID_MODEL=HTS726060M9AT00
517 ID_SERIAL=MRH401M4G6UM9B
521 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
522 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
525 kay@pim:~> tree /dev/disk
528 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
529 | `-- IBM-Memory_Key -> ../../sda
531 | |-- swap -> ../../hda1
532 | |-- date -> ../../sda1
533 | `-- home -> ../../hda3
535 |-- 2E08712B0870F2E7 -> ../../hda3
536 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
537 |-- E845-7A89 -> ../../sda1
538 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
540 The IMPORT= operation will import these keys in the environment and make
541 it available for later PROGRAM= and RUN= executed programs. The keys are
542 also stored in the udevdb and can be queried from there with one of the
545 o A few binaries are silently added to the repository, which can be used
546 to replay kernel events from initramfs instead of using coldplug. udevd
547 can be instructed now to queue-up events while the stored events from
548 initramfs are filled into the udevd-queue. This code is still under
549 development and there is no documentation now besides the code itself.
550 The additional binaries get compiled, but are not installed by default.
552 o There is also a temporary fix for a performance problem where too many
553 events happen in parallel and every event needs to parse the rules.
554 udev can now read precompiled rules stored on disk. This is likely to be
555 replaced by a more elegant solution in a future udev version.
559 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
560 Fix for libsysfs not to expect this file was added.
564 All rules are applied now, but only the first matching rule with a NAME-key
565 will be applied. All later rules with NAME-key are completely ignored. This
566 way system supplied symlinks or permissions gets applied to user-defined
570 Please check your rules setup, if you may need to add OPTIONS="last_rule"
571 to some rules, to keep the old behavior.
573 The rules are read on "remove"-events too. That makes is possible to match
574 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
575 instruct udev to ignore an event (OPTIONS="ignore_device").
576 The new ACTION-key may be used to let a rule act only at a "remove"-event.
578 The new RUN-key supports rule-based execution of programs after device-node
579 handling. This is meant as a general replacement for the dev.d/-directories
580 to give fine grained control over the execution of programs.
582 The %s{}-sysfs format char replacement values are searched at any of the
583 devices in the device chain now, not only at the class-device.
585 We support log priority levels now. The value udev_log in udev.conf is used
586 to determine what is printed to syslog. This makes it possible to
587 run a version with compiled-in debug messages in a production environment
588 which is sometimes needed to find a bug.
589 It is still possible to supress the inclusion of _any_ syslog usage with
590 USE_LOG=false to create the smallest possible binaries if needed.
591 The configured udev_log value can be overridden with the environment variable
596 Possible use of a system-wide klibc:
597 make USE_KLIBC=true KLCC=/usr/bin/klcc all
598 will link against an external klibc and our own version will be ignored.
602 We support an unlimited count of symlinks now.
604 If USE_STATIC=true is passed to a glibc build, we link statically and use
605 a built-in userdb parser to resolve user and group names.
607 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
608 we walk up the chain of physical devices to find a match.
610 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
611 easy to skip certain attribute matches without composing rules with weird
612 character class negations like:
613 KERNEL="[!s][!c][!d]*"
614 this can now be replaced with:
616 The current simple '=' is still supported, and should work as it does today,
617 but existing rules should be converted if possible, to be better readable.
619 We have new ENV{}== key now, to match against a maximum of 5 environment
622 udevstart is its own binary again, because we don't need co carry this araound
623 with every forked event.