5 The udev daemon moved to /lib/udev/udevd. Non-systemd init systems
6 and non-dracut initramfs image generators need to change the init
7 scripts. Alternatively the udev build needs to move udevd back to
8 /sbin or create a symlink in /sbin, which is not done by default.
10 The path_id, usb_id, input_id tools are built-in commands now and
11 the stand-alone tools do not exist anymore. Static lists of file in
12 initramfs generators need to be updated. For testing, the commands
13 can still be executed standalone with 'udevadm test-builtin <cmd>'.
15 The fusectl filesystem is no longer mounted directly from udev.
16 Systemd systems will take care of mounting fusectl and configfs
17 now. Non-systemd systems need to ship their own rule if they
18 need these filesystems auto-mounted.
20 The long deprecated keys: SYSFS=, ID=, BUS= have been removed.
22 The support for 'udevadm trigger --type=failed, and the
23 RUN{fail_event_on_error} attribute was removed.
25 The udev control socket is now created in /run/udev/control
26 and no longer as an abstract namespace one.
32 The udev-acl extra is no longer enabled by default now. To enable it,
33 --enable-udev_acl needs to be given at ./configure time. On systemd
34 systems, the udev-acl rules prevent it from running as the functionality
41 Udev now enables kernel media-presence polling if available. Part
42 of udisks optical drive tray-handling moved to cdrom_id: The tray
43 is locked as soon as a media is detected to enable the receiving
44 of media-eject-request events. Media-eject-request events will
47 Libudev enumerate is now able to enumerate a subtree of a given
50 The mobile-action-modeswitch modeswitch tool was deleted. The
51 functionality is provided by usb_modeswitch now.
57 The systemd service files require systemd version 28. The systemd
58 socket activation make it possible now to start 'udevd' and 'udevadm
63 Fix bug in control message handling, which can lead to a failing
64 udevadm control --exit. Thanks to Jürg Billeter for help tracking
71 We require at least Linux kernel 2.6.32 now. Some platforms might
72 require a later kernel that supports accept4() and similar, or
73 need to backport the trivial syscall wiring to the older kernels.
75 The hid2hci tool moved to the bluez package and was removed.
77 Many of the extras can be --enable/--disabled at ./configure
78 time. The --disable-extras option was removed. Some extras have
79 been disabled by default. The current options and their defaults
80 can be checked with './configure --help'.
86 Udev logs a warning now if /run is not writable at udevd
87 startup. It will still fall back to /dev/.udev, but this is
90 The running udev daemon can now cleanly shut down with:
91 udevadm control --exit
93 Udev in initramfs should clean the state of the udev database
94 with: udevadm info --cleanup-db which will remove all state left
95 behind from events/rules in initramfs. If initramfs uses
96 --cleanup-db and device-mapper/LVM, the rules in initramfs need
97 to add OPTIONS+="db_persist" for all dm devices. This will
98 prevent removal of the udev database for these devices.
100 Spawned programs by PROGRAM/IMPORT/RUN now have a hard timeout of
101 120 seconds per process. If that timeout is reached the spawned
102 process will be killed. The event timeout can be overwritten with
105 If systemd is used, udev gets now activated by netlink data.
106 Systemd will bind the netlink socket which will buffer all data.
107 If needed, such setup allows a seemless update of the udev daemon,
108 where no event can be lost during a udevd update/restart.
109 Packages need to make sure to: systemctl stop udev.socket udev.service
110 or 'mask' udev.service during the upgrade to prevent any unwanted
111 auto-spawning of udevd.
112 This version of udev conflicts with systemd version below 25. The
113 unchanged service files will not wirk correctly.
119 The udev runtime data moved from /dev/.udev/ to /run/udev/. The
120 /run mountpoint is supposed to be a tmpfs mounted during early boot,
121 available and writable to for all tools at any time during bootup,
122 it replaces /var/run/, which should become a symlink some day.
124 If /run does not exist, or is not writable, udev will fall back using
127 On systemd systems with initramfs and LVM used, packagers must
128 make sure, that the systemd and initramfs versions match. The initramfs
129 needs to create the /run mountpoint for udev to store the data, and
130 mount this tmpfs to /run in the rootfs, so the that the udev database
131 is preserved for the udev version started in the rootfs.
133 The command 'udevadm info --convert-db' is gone. The udev daemon
134 itself, at startup, converts any old database version if necessary.
136 The systemd services files have been reorganized. The udev control
137 socket is bound by systemd and passed to the started udev daemon.
138 The udev-settle.service is no longer active by default. Services which
139 can not handle hotplug setups properly need to actively pull it in, to
140 act like a barrier. Alternatively the settle service can be unconditionally
141 'systemctl'enabled, and act like a barrier for basic.target.
143 The fstab_import callout is no longer built or installed. Udev
144 should not be used to mount, does not watch changes to fstab, and
145 should not mirror fstab values in the udev database.
151 New and updated keymaps.
157 The udev database has changed, After installation of a new udev
158 version, 'udevadm info --convert-db' should be called, to let the new
159 udev/libudev version read the already stored data.
161 udevadm now supports quoting of property values, and prefixing of
163 $ udevadm info --export --export-prefix=MY_ --query=property -n sda
166 MY_DEVNAME='/dev/sda'
170 libudev now supports:
171 udev_device_get_is_initialized()
172 udev_enumerate_add_match_is_initialized()
173 to be able to skip devices the kernel has created , but udev has
176 libudev now supports:
177 udev_device_get_usec_since_initialized()
178 to retrieve the "age" of a udev device record.
180 GUdev supports a more generic GUdevEnumerator class, udev TAG
181 handling, device initialization and timestamp now.
183 The counterpart of /sys/dev/{char,block}/$major:$minor,
184 /dev/{char,block}/$major:$minor symlinks are now unconditionally
185 created, even when no rule files exist.
187 New and updated keymaps.
193 GUdev moved from /usr to /.
203 Persistent network naming rules are disabled inside of Qemu/KVM now.
205 New and updated keymaps.
207 Udev gets unconditionally enabled on systemd installations now. There
208 is no longer the need to to run 'systemctl enable udev.service'.
222 New and fixed keymaps.
224 Install systemd service files if applicable.
230 All distribution specific rules are removed from the udev source tree,
231 most of them are no longer needed. The Gentoo rules which allow to support
232 older kernel versions, which are not covered by the default rules anymore
233 has moved to rules/misc/30-kernel-compat.rules.
239 The option --debug-trace and the environemnt variable UDEVD_MAX_CHILDS=
240 was removed from udevd.
242 Udevd now checks the kernel commandline for the following variables:
243 udev.log-priority=<syslog priority>
244 udev.children-max=<maximum number of workers>
245 udev.exec-delay=<seconds to delay the execution of RUN=>
246 to help debuging coldplug setups where the loading of a kernel
247 module crashes the system.
249 The subdirectory in the source tree rules/packages has been renamed to
250 rules/arch, anc contains only architecture specific rules now.
260 Now the udev daemon itself, does on startup:
261 - copy the content of /lib/udev/devices to /dev
262 - create the standard symlinks like /dev/std{in,out,err},
263 /dev/core, /dev/fd, ...
264 - use static node information provided by kernel modules
265 and creates these nodes to allow module on-demand loading
266 - possibly apply permissions to all ststic nodes from udev
267 rules which are annotated to match a static node
269 The default mode for a device node is 0600 now to match the kernel
270 created devtmpfs defaults. If GROUP= is specified and no MODE= is
271 given the default will be 0660.
277 Udev now gradually starts to pass control over the primary device nodes
278 and their names to the kernel, and will in the end only manage the
279 permissions of the node, and possibly create additional symlinks.
280 As a first step NAME="" will be ignored, and NAME= setings with names
281 other than the kernel provided name will result in a logged warning.
282 Kernels that don't provide device names, or devtmpfs is not used, will
283 still work as they did before, but it is strongly recommended to use
284 only the same names for the primary device node as the recent kernel
285 provides for all devices.
289 Fix broken firmware loader search path.
295 "udevadm trigger" defaults to "change" events now instead of "add"
296 events. The "udev boot script" might need to add "--action=add" to
297 the trigger command if not already there, in case the initial coldplug
298 events are expected as "add" events.
300 The option "all_partitons" was removed from udev. This should not be
301 needed for usual hardware. Udev can not safely make assumptions
302 about non-existing partition major/minor numbers, and therefore no
303 longer provide this unreliable and unsafe option.
305 The option "ignore_remove" was removed from udev. With devtmpfs
306 udev passed control over device nodes to the kernel. This option
307 should not be needed, or can not work as advertised. Neither
308 udev nor the kernel will remove device nodes which are copied from
309 the /lib/udev/devices/ directory.
311 All "add|change" matches are replaced by "!remove" in the rules and
312 in the udev logic. All types of events will update possible symlinks
313 and permissions, only "remove" is handled special now.
315 The modem modeswitch extra was removed and the external usb_modeswitch
316 program should be used instead.
318 New and fixed keymaps.
328 Kernels with SYSFS_DEPRECATED=y are not supported since a while. Many users
329 depend on the current sysfs layout and the information not available in the
330 deprecated layout. All remaining support for the deprecated sysfs layout is
335 Fix for a possible endless loop in the new input_id program.
341 The option "ignore_device" does no longer exist. There is no way to
342 ignore an event, as libudev events can not be suppressed by rules.
343 It only prevented RUN keys from being executed, which results in an
344 inconsistent behavior in current setups.
346 BUS=, SYSFS{}=, ID= are long deprecated and should be SUBSYSTEM(S)=,
347 ATTR(S){}=, KERNEL(S)=. It will cause a warning once for every rule
350 The support for the deprecated IDE devices has been removed from the
351 default set of rules. Distros who still care about non-libata drivers
352 need to add the rules to the compat rules file.
354 The ID_CLASS property on input devices has been replaced by the more accurate
355 set of flags ID_INPUT_{KEYBOARD,KEY,MOUSE,TOUCHPAD,TABLET,JOYSTICK}. These are
356 determined by the new "input_id" prober now. Some devices, such as touchpads,
357 can have several classes. So if you previously had custom udev rules which e. g.
358 checked for ENV{ID_CLASS}=="kbd", you need to replace this with
359 ENV{ID_INPUT_KEYBOARD}=="?*".
365 To support DEVPATH strings larger than the maximum file name length, the
366 private udev database format has changed. If some software still reads the
367 private files in /dev/.udev/, which it shouldn't, now it's time to fix it.
368 Please do not port anything to the new format again, everything in /dev/.udev
369 is and always was private to udev, and may and will change any time without
372 Multiple devices claiming the same names in /dev are limited to symlinks
373 only now. Mixing identical symlink names and node names is not supported.
374 This reduces the amount of data in the database significantly.
376 NAME="%k" causes a warning now. It's is and always was completely superfluous.
377 It will break kernel supplied DEVNAMEs and therefore it needs to be removed
380 Most NAME= instructions got removed. Kernel 2.6.31 supplies the needed names
381 if they are not the default. To support older kernels, the NAME= rules need to
382 be added to the compat rules file.
384 Symlinks to udevadm with the old command names are no longer resolved to
385 the udevadm commands.
387 The udev-acl tool got adopted to changes in ConsoleKit. Version 0.4.1 is
390 The option "last_rule" does no longer exist. Its use breaks too many
391 things which expect to be run from independent later rules, and is an idication
392 that something needs to be fixed properly instead.
394 The gudev API is no longer marked as experimental,
395 G_UDEV_API_IS_SUBJECT_TO_CHANGE is no longer needed. The gudev introspection
396 is enabled by default now. Various projects already depend on introspection
397 information to bind dynamic languages to the gudev interfaces.
403 The udevadm trigger "--retry-failed" option, which is replaced since quite
404 a while by "--type=failed" is removed.
406 The failed tracking was not working at all for a few releases. The RUN
407 option "ignore_error" is replaced by a "fail_event_on_error" option, and the
408 default is not to track any failing RUN executions.
410 New keymaps, new modem, hid2hci updated.
414 Fix possible crash in udevd when worker processes are busy, rules are
415 changed at the same time, and workers get killed to reload the rules.
421 Properties set with ENV{.FOO}="bar" are marked private by starting the
422 name with a '.'. They will not be stored in the database, and not be
423 exported with the event.
425 Firmware files are looked up in:
426 /lib/firmware/updates/$(uname -r)
427 /lib/firmware/updates
428 /lib/firmware/$(uname -r)
432 ATA devices switched the property from ID_BUS=scsi to ID_BUS=ata.
433 ata_id, instead of scsi_id, is the default tool now for ATA devices.
439 The configure options have changed because another library needs to be
440 installed in a different location. Instead of exec_prefix and udev_prefix,
441 libdir, rootlibdir and libexecdir are used. The Details are explained in
444 Event processes now get re-used after they handled an event. This reduces
445 the number of forks and the pressure on the CPU significantly, because
446 cloned event processes no longer cause page faults in the main daemon.
447 After the events have settled, a few worker processes stay around for
448 future events, all others get cleaned up.
450 To be able to use signalfd(), udev depends on kernel version 2.6.25 now.
451 Also inotify support is mandatory now to run udev.
453 The format of the queue exported by the udev damon has changed. There is
454 no longer a /dev/.udev/queue/ directory. The current event queue can be
455 accessed with udevadm settle and libudedv.
457 Libudev does not have the unstable API header anymore. From now on,
458 incompatible changes will be handled by bumping the library major version.
460 To build udev from the git tree gtk-doc is needed now. The tarballs will
461 build without it and contain the pre-built documentation. An online copy
463 http://www.kernel.org/pub/linux/utils/kernel/hotplug/libudev/
465 The tools from the udev-extras repository have been merged into the main
466 udev repository. Some of the extras have larger external dependencies, and
467 they can be disabled with the configure switch --disable-extras.
473 The program vol_id and the library libvolume_id are removed from the
474 repository. Libvolume_id is merged with libblkid from the util-linux-ng
475 package. Persistent disk links for label and uuid depend on the
476 util-linux-ng version (2.15) of blkid now. Older versions of blkid
477 can not be used with udev.
479 Libudev allows to subscribe to udev events. To prevent unwanted messages
480 to be delivered, and waking up the subscribing process, a filter can be
481 installed, to drop messages inside a kernel socket filter. The filters
482 match on the <subsytem>:<devtype> properties of the device.
483 This is part of the ongoing effort to replace HAL, and switch current
484 users over to directly use libudev.
485 Libudev is still marked as experimental, and its interface might
486 eventually change if needed, but no major changes of the currently exported
487 interface are expected anymore, and a first stable release should happen
490 A too old kernel (2.6.21) or a kernel with CONFIG_SYSFS_DEPRECATED
491 is not supported since while and udevd will log an error message at
492 startup. It should still be able to boot-up, but advanced rules and system
493 services which depend on the information not available in the old sysfs
494 format will fail to work correctly.
496 DVB device naming is supplied by the kernel now. In case older kernels
497 need to be supported, the old shell script should be added to a compat
504 The processed udev events get send back to the netlink socket. Libudev
505 provides access to these events. This is work-in-progress, to replace
506 the DeviceKit daemon functionality directly with libudev. There are
507 upcoming kernel changes to allow non-root users to subcribe to these
514 "udevadm settle" now optionally accepts a range of events to wait for,
515 instead of waiting for "all" events.
521 The installed watch for block device metadata changes is now removed
522 during event hadling, because some (broken) tools may be called from udev
523 rules and (wrongly) open the device with write access. After the finished
524 event handling the watch is restored.
530 Device nodes can be watched for changes with inotify with OPTIONS="watch".
531 If closed after being opened for writing, a "change" uevent will occur.
532 /dev/disk/by-{label,uuid}/* symlinks will be automatically updated.
538 The udevadm test command has no longer a --force option, nodes and symlinks
539 are always updated with a test run now.
541 The udevd daemon can be started with --resolve-names=never to avoid all user
542 and group lookups (e.g. in cut-down systems) or --resolve-names=late to
543 lookup user and groups every time events are handled.
549 We are currently merging the Ubuntu rules in the udev default rules,
550 and get one step closer to provide a common Linux /dev setup, regarding
551 device names, symlinks, and default device permissions. On udev startup,
552 we now expect the following groups to be resolvable to their ids with
554 disk, cdrom, floppy, tape, audio, video, lp, tty, dialout, kmem.
555 LDAP setups need to make sure, that these groups are always resolvable at
556 bootup, with only the rootfs mounted, and without network access available.
558 Some systems may need to add some new, currently not used groups, or need
559 to add some users to new groups, but the cost of this change is minimal,
560 compared to the pain the current, rather random, differences between the
561 various distributions cause for upstream projects and third-party vendors.
563 In general, "normal" users who log into a machine should never be a member
564 of any such group, but the device-access should be managed by dynamic ACLs,
565 which get added and removed for the specific users on login/logout and
566 session activity/inactivity. These groups are only provided for custom setups,
567 and mainly system services, to allow proper privilege separation.
568 A video-streaming daemon uid would be a member of "audio" and "video", to get
569 access to the sound and video devices, but no "normal" user should ever belong
570 to the "audio" group, because he could listen to the built-in microphone with
571 any ssh-session established from the other side of the world.
573 /dev/serial/by-{id,path}/ now contains links for ttyUSB devices,
574 which do not depend on the kernel device name. As usual, unique
575 devices - only a single one per product connected, or a real
576 USB serial number in the device - are always found with the same
577 name in the by-id/ directory.
578 Completely identical devices may overwrite their names in by-id/
579 and can only be found reliably in the by-path/ directory. Devices
580 specified by by-path/ must not change their connection, like the
581 USB port number they are plugged in, to keep their name.
583 To support some advanced features, Linux 2.6.22 is the oldest supported
584 version now. The kernel config with enabled SYSFS_DEPRECATED is no longer
585 supported. Older kernels should still work, and devices nodes should be
586 reliably created, but some rules and libudev will not work correctly because
587 the old kernels do not provide the expected information or interfaces.
593 Fix for a possible segfault while swapping network interface names in udev
600 The group "video" is part of the default rules now.
604 Bugfix for kernels using SYSFS_DEPRECATED* option and finding parent
605 block devices in some cases. No common distro uses this option anymore,
606 and we do not get enough testing for this and recent udev versions. If
607 this option is not needed to run some old distro with a new kernel,
608 it should be disabled in the kernel config.
610 Bugfix for the $links substitution variable, which may crash if no links
611 are created. This should not happen in usual setups because we always
612 create /dev/{block,char}/ links.
614 The strings of the parsed rules, which are kept in memory, no longer
615 contain duplicate entries, or duplicate tails of strings. This, and the
616 new rules parsing/matching code reduces the total in-memory size of
617 a huge distro rule sets to 0.08 MB, compared to the 1.2MB of udev
620 The export of DEVTYPE=disk/partition got removed from the default
621 rules. This value is available from the kernel. The pnp shell script
622 modprobe hack is removed from the default rules. ACPI devices have _proper_
623 modalias support and take care of the same functionality.
624 Installations which support old kernels, but install current default
625 udev rules may want to add that to the compat rules file.
627 Libvolume_id now always probes for all known filesystems, and does not
628 stop at the first match. Some filesystems are marked as "exclusive probe",
629 and if any other filesytem type matches at the same time, libvolume_id
630 will, by default, not return any probing result. This is intended to prevent
631 mis-detection with conflicting left-over signatures found from earlier
632 file system formats. That way, we no longer depend on the probe-order
633 in case of multiple competing signatures. In some setups the kernel allows
634 to mount a volume with just the old filesystem signature still in place.
635 This may damage the new filesystem and cause data-loss, just by mounting
636 it. Because volume_id can not decide which one the correct signature is,
637 the wrong signatures need to be removed manually from the volume, or the
638 volume needs to be reformatted, to enable filesystem detection and possible
643 Fix segfault if compiled without optimization and dbg() does not get
644 compiled out and uses variables which are not available.
648 Bugfixes. (And maybe new bugs. :))
650 The rule matching engine got converted from a rule list to a token
651 array which reduced the in-memory rules representation of a full
652 featured distros with thousends of udev rules from 1.2MB to 0.12 MB.
653 Limits like 5 ENV and ATTR matches, and one single instance for most
654 other keys per rule are gone.
656 The NAME assignment is no longer special cased. If later rules assign
657 a NAME value again, the former value will be overwritten. As usual
658 for most other keys, the NAME value can be protected by doing a final
659 assignment with NAME:="<value>".
661 All udev code now uses libudev, which is also exported. The library
662 is still under development, marked as experimental, and its interface
663 may change as long as the DeviceKit integration is not finished.
665 Many thanks to Alan Jenkins for his continuous help, and finding and
666 optimizing some of the computing expensive parts.
672 Kernel devices and device nodes are connected now by reverse indizes in
673 /sys and /dev. A device number retrieved by a stat() or similar, the
674 kernel device directory can be found by looking up:
675 /sys/dev/{block,char}/<maj>:<min>
676 and the device node of the same device by looking up:
677 /dev/{block,char}/<maj>:<min>
681 Fix recently introduced bug, which caused a compilation without large
682 file support, where vol_id does not recognize raid signatures at the end
685 Firewire disks now create both, by-id/scsi-* and by-id/ieee-* links.
686 Seems some kernel versions prevent the creation of the ieee-* links,
687 so people used the scsi-* link which disappeared now.
689 More libudev work. Almost all udevadm functionality comes from libudev
692 udevadm trigger has a new option --type, which allows to trigger events
693 for "devices", for "subsystems", or "failed" devices. The old option
694 --retry-failed" still works, but is no longer mentioned in the man page.
700 The udevadm info --device-id-of-file= output has changed to use
701 the obvious format. Possible current users should use the --export
702 option which is not affected.
704 The old udev commands symlinks to udevadm are not installed, if
705 these symlinks are used, a warning is printed.
711 Optical drive's media is no longer probed for raid signatures,
712 reading the end of the device causes some devices to malfunction.
713 Also the offset of the last session found is used now to probe
716 The volume_id library got a major version number update to 1,
717 some deprecated functions are removed.
719 A shared library "libudev" gets installed now to provide access
720 to udev device information. DeviceKit, the successor of HAL, will
721 need this library to access the udev database and search sysfs for
723 The library is currently in an experimental state, also the API is
724 expected to change, as long as the DeviceKit integration is not
729 We use ./configure now. See INSTALL for details. Current
732 "/usr" - prefix for man pages, include files
734 "" - the root filesystem, prefix for libs and binaries
738 "lib" - directory name for libraries, not a path name
739 multilib 64bit systems may use "lib64" instead of "lib"
741 compile-in verbose debug messages
743 disable all logging and compile-out all log strings
745 link against SELInux libraries, to set the expected context
748 In the default rules, the group "disk" gets permissions 0660 instead
749 of 0640. One small step closer to unify distro rules. Some day, all
750 distros hopefully end up with the same set of rules.
752 No symlinks to udevadm are installed anymore, if they are still needed,
753 they should be provided by the package.
759 Default udev rules, which are not supposed to be edited by the user, should
760 be placed in /lib/udev/rules.d/ now, to make it clear that they are private to
761 the udev package and will be replaced with an update. Udev will pick up rule
763 /lib/udev/rules.d/ - default installed rules
764 /etc/udev/rules.d/ - user rules + on-the-fly generated rules
765 /dev/.udev/rules.d/ - temporary non-persistent rules created after bootup
766 It does not matter in which directory a rule file lives, all files are sorted
769 To help creating /dev/root, we have now:
770 $ udevadm info --export --export-prefix="ROOT_" --device-id-of-file=/
773 In case the current --device-id-of-file is already used, please switch to
774 the --export format version, it saves the output parsing and the old
775 format will be changed to use ':' as a separator, like the format in the
780 Fix cdrom_id to properly recognize blank media.
786 Tape drive id-data is queried from /dev/bsg/* instead of the tape
787 nodes. This avoids rewinding tapes on open().
793 The symlinks udevcontrol and udevtrigger are no longer installed by
796 The scsi_id program does not depend on sysfs anymore. It can speak
797 SGv4 now, so /dev/bsg/* device nodes can be used, to query SCSI device
798 data, which should solve some old problems with tape devices, where
799 we better do not open all tape device nodes to identify the device.
805 The cdrom_id program is replaced by an advanced version, which can
806 detect most common device types, and also properties of the inserted
807 media. This is part of moving some basic functionality from HAL into
808 udev (and the kernel).
814 The last WAIT_FOR_SYSFS rule is removed from the default rules.
816 The symlinks to udevadm for the debugging tools: udevmonitor and
817 udevtest are no longer created.
819 The symlinks to the udevadm man page for the old tool names are
822 Abstract namespace sockets paths in RUN+="socket:@<path>" rules,
823 should be prefixed with '@' to indicate that the path is not a
834 Udevstart is removed from the tree, it did not get installed for
835 a long time now, and is long replaced by trigger and settle.
841 All udev tools are merged into a single binary called udevadm.
842 The old names of the tools are built-in commands in udevadm now.
843 Symlinks to udevadm, with the names of the old tools, provide
844 the same functionality as the standalone tools. There is also
845 only a single udevadm.8 man page left for all tools.
847 Tools like mkinitramfs should be checked, if they need to include
848 udevadm in the list of files.
858 The etc/udev/rules.d/ directory now contains a default set of basic
859 udev rules. This initial version is the result of a rules file merge
860 of Fedora and openSUSE. For these both distros only a few specific
861 rules are left in their own file, named after the distro. Rules which
862 are optionally installed, because they are only valid for a specific
863 architecture, or rules for subsystems which are not always used are
864 in etc/udev/packages/.
870 Dynamic rules can be created in /dev/.udev/rules.d/ to trigger
871 actions by dynamically created rules.
873 SYMLINK=="<value>" matches agains the entries in the list of
874 currently defined symlinks. The links are not created in the
875 filesystem at that point in time, but the values can be matched.
877 RUN{ignore_error}+="<program>" will ignore any exit code from the
878 program and not record as a failed event.
884 Final merge of patches/features from the Ubuntu package.
890 Control characters in filesystem label strings are no longer silenty
891 removed, but hex-encoded, to be able to uniquely identify the device
892 by its symlink in /dev/disk/by-label/.
893 If libvolume_id is used by mount(8), LABEL= will work as expected,
894 if slashes or other characters are used in the label string.
896 To test the existence of a file, TEST=="<file>" and TEST!="<file>"
897 can be specified now. The TEST key accepts an optional mode mask
898 TEST{0100}=="<is executable file>".
900 Scsi_id now supports a mode without expecting scsi-specific sysfs
901 entries to allow the extraction of cciss-device persistent properties.
907 In the future, we may see uuid's which are just simple character
908 strings (see the DDF Raid Specification). For that reason vol_id now
909 exports ID_FS_UUID_SAFE, just like ID_FS_LABEL_SAFE. For things like
910 the creation of symlinks, the *_SAFE values ensure, that no control
911 or whitespace characters are used in the filename.
913 Possible users of libvolume_id, please use the volume_id_get_* functions.
914 The public struct will go away in a future release of the library.
920 Removal of useless extras/eventrecorder.sh.
930 The directory multiplexer for dev.d/ and hotplug.d are finally removed
931 from the udev package.
937 Symlinks can have priorities now, the priority is assigned to the device
938 and specified with OPTIONS="link_priority=100". Devices with higher
939 priorities overwrite the symlinks of devices with lower priorities.
940 If the device that currently owns the link, goes away, the symlink
941 will be removed, and recreated, pointing to the next device with the
942 highest actual priority. This should make /dev/disk/by-{label,uuid,id}
943 more reliable, if multiple devices contain the same metadata and overwrite
946 The dasd_id program is removed from the udev tree, and dasdinfo, with the
947 needed rules, are part of the s390-tools now.
949 Please add KERNEL=="[0-9]*:[0-9]*" to the scsi wait-for-sysfs rule,
950 we may get the scsi sysfs mess fixed some day, and this will only catch
951 the devices we are looking for.
953 USB serial numbers for storage devices have the target:lun now appended,
954 to make it possibble to distinguish broken multi-lun devices with all
955 the same SCSI identifiers.
957 Note: The extra "run_directory" which searches and executes stuff in
958 /etc/hotplug.d/ and /etc/dev.d/ is long deprecated, and will be removed
959 with the next release. Make sure, that you don't use it anymore, or
960 provides your own implementation of that inefficient stuff.
961 We are tired of reports about a "slow udev", because these directories
962 contain stuff, that runs with _every_ event, instead of using rules,
963 that run programs only for the matching events.
973 DRIVER== will match only for devices that actually have a real
974 driver. DRIVERS== must be used, if parent devices should be
975 included in the match.
977 Libvolume_id's "linux_raid" detection needed another fix.
985 Add additional check to volume_id detection of via_raid, cause
986 some company decided to put a matching pattern all over the empty
987 storage area of their music players.
991 Fix path_id for SAS devices.
995 The udev daemon can be started with --debug-trace now, which will
996 execute all events serialized to get a chance to catch a possible
997 action that crashes the box.
999 A warning is logged, if PHYSDEV* keys, the "device" link, or a parent
1000 device attribute like $attr{../file} is used, only WAIT_FOR_SYSFS rules
1001 are excluded from the warning. Referencing parent attributes directly
1002 may break when something in the kernel driver model changes. Udev will
1003 just find the attribute by walking up the parent chain.
1005 Udevtrigger now sorts the list of devices depending on the device
1006 dependency, so a "usb" device is triggered after the parent "pci"
1011 Revert persistent-storage ata-serial '_' '-' replacement.
1017 Udevtrigger can now filter the list of devices to be triggered. Matches
1018 for subsystems or sysfs attributes can be specified.
1020 The entries in /dev/.udev/queue and /dev/.udev/failed have changed to
1021 zero-sized files to avoid pointing to /sys and confuse broken tools which
1022 scan the /dev directory. To retry failed events, udevtrigger --retry-failed
1025 The rules and scripts to create udev rules for persistent network
1026 devices and optical drives are in the extras/rules_generator directory
1027 now. If you use something similar, please consider replacing your own
1028 version with this, to share the support effort. The rule_generator
1029 installs its own rules into /etc/udev/rules.d.
1031 The cdrom_id tool installs its own rule now in /etc/udev/rules.d, cause
1032 the rule_generator depends on cdrom_id to be called in an earlier rule.
1038 Renaming of some key names (the old names still work):
1039 BUS -> SUBSYSTEMS, ID -> KERNELS, SYSFS -> ATTRS, DRIVER -> DRIVERS.
1040 (The behavior of the key DRIVER will change soon in one of the next
1041 releases, to match only the event device, please switch to DRIVERS
1042 instead. If DRIVER is used, it will behave like DRIVERS, but an error
1044 With the new key names, we have a more consistent and simpler scheme.
1045 We can match the properties of the event device only, with: KERNEL,
1046 SUBSYSTEM, ATTR, DRIVER. Or include all the parent devices in the match,
1047 with: KERNELS, SUBSYSTEMS, ATTRS, DRIVERS. ID, BUS, SYSFS, DRIVER are no
1048 longer mentioned in the man page and should be switched in the rule
1051 ATTR{file}="value" can be used now, to write to a sysfs file of the
1052 event device. Instead of:
1053 ..., SYSFS{type}=="0|7|14", RUN+="/bin/sh -c 'echo 60 > /sys$$DEVPATH/timeout'"
1055 ..., ATTR{type}=="0|7|14", ATTR{timeout}="60"
1057 All the PHYSDEV* keys are deprecated and will be removed from a
1059 PHYDEVPATH - is the path of a parent device and should not be
1061 PHYSDEVBUS - is just a SUBSYSTEM value of a parent, and can be
1062 matched with SUBSYSTEMS==
1063 PHYSDEVDRIVER - for bus devices it is available as ENV{DRIVER}.
1064 Newer kernels will have DRIVER in the environment,
1065 for older kernels udev puts in. Class device will
1066 no longer carry this property of a parent and
1067 DRIVERS== can be used to match such a parent value.
1068 Note that ENV{DRIVER} is only available for a few bus devices, where
1069 the driver is already bound at device event time. On coldplug, the
1070 events for a lot devices are already bound to a driver, and they will have
1071 that value set. But on hotplug, at the time the kernel creates the device,
1072 it can't know what driver may claim the device after that, therefore
1073 in most cases it will be empty.
1075 Failed events should now be re-triggered with:
1076 udevtrigger --retry-failed.
1077 Please switch to this command, so we keep the details of the /dev/.udev/failed/
1078 files private to the udev tools. We may need to switch the current symlink
1079 target, cause some obviously broken tools try to scan all files in /dev
1080 including /dev/.udev/, find the links to /sys and end up stat()'ing sysfs files
1081 million times. This takes ages on slow boxes.
1083 The udevinfo attribute walk (-a) now works with giving a device node
1084 name (-n) instead of a devpath (-p). The query now always works, also when
1085 no database file was created by udev.
1087 The built-in /etc/passwd /etc/group parser is removed, we always depend on
1088 getpwnam() and getgrnam() now. One of the next releases will depend on
1089 fnmatch() and may use getopt_long().
1093 Bugfixes and small improvements.
1097 Fix path_id for recent kernels.
1103 Added support for swapping network interface names, by temporarily
1104 renaming the device and wait for the target name to become free.
1108 The built-in MODALIAS key and substitution is removed.
1112 The binary firmware helper is replaced by the usual simple
1113 shell script. Udevsend is removed from the tree.
1121 Some more keys require the correct use of '==' and '=' depending
1122 on the kind of operation beeing an assignment or a match. Rules
1123 with invalid operations are skipped and logged to syslog. Please
1124 test with udevtest if the parsing of your rules throws errors and
1125 fix possibly broken rules.
1129 Provide "udevsettle" to wait for all current udev events to finish.
1130 It also watches the current kernel netlink queue by comparing the
1131 even sequence number to make sure that there are no current pending
1132 events that have not already arrived in the daemon.
1136 Fix rule to skip persistent rules for removable IDE devices, which
1137 also skipped optical IDE drives.
1139 All *_id program are installed in /lib/udev/ by default now.
1141 No binary is stripped anymore as this should be done in the
1142 packaging process and not at build time.
1144 libvolume_id is provided as a shared library now and vol_id is
1145 linked against it. Also one of the next HAL versions will require
1146 this library, and the HAL build process will also require the
1147 header file to be installed. The copy of the same code in HAL will
1148 be removed to have only a single copy left on the system.
1152 Add persistent links for SCSI tapes. The rules file is renamed
1153 to 60-persistent-storage.rules.
1155 Create persistent path for usb devices. Can be used for all sorts
1156 of devices that can't be distinguished by other properties like
1157 multiple identical keyboards and mice connected to the same box.
1159 Provide "udevtrigger" program to request events on coldplug. The
1160 shell script is much too slow with thousends of devices.
1164 Fix persistent disk rules to exclude removable IDE drives.
1166 Warn if %e, $modalias or MODALIAS is used.
1170 Fix queue export, which wasn't correct for subsequent add/remove
1171 events for the same device.
1175 Fix cramfs detection on big endian.
1177 Make WAIT_FOR_SYSFS usable in "normal" rules and silent if the whole
1182 If BUS== and SYSFS{}== have been used in the same rule, the sysfs
1183 attributes were only checked at the parent device that matched the
1184 by BUS requested subsystem. Fix it to also look at the device we
1185 received the event for.
1187 Build variable CROSS has changed to CROSS_COMPILE to match the kernel
1192 Fix a bug where NAME="" would prevent RUN from beeing executed.
1194 RUN="/bin/program" does not longer automatically add the subsystem
1195 as the first parameter. This is from the days of /sbin/hotplug
1196 which is dead now and it's just confusing to need to add a space at
1197 the end of the program name to prevent this.
1198 If you use rules that need the subsystem as the first parameter,
1199 like the old "udev_run_hotlugd" and "udev_run_devd", add the subsystem
1200 to the key like RUN+="/bin/program $env{SUBSYSTEM}".
1204 The udev man page has moved to udev(7) as it does not describe a command
1205 anymore. The programs udev, udevstart and udevsend are no longer installed
1206 by default and must be copied manually, if they should be installed or
1207 included in a package.
1209 Fix a bug where "ignore_device" could run earlier collected RUN keys before
1210 the ignore rule was applied.
1212 More preparation for future sysfs changes. usb_id and scsi_id no longer
1213 depend on a magic order of devices in the /devices chain. Specific devices
1214 should be requested by their subsytem.
1216 This will always find the scsi parent device without depending on a specific
1218 dev = sysfs_device_get(devpath);
1219 dev_usb = sysfs_device_get_parent_with_subsystem(dev, "scsi");
1221 The "device" link in the current sysfs layout will be automatically
1222 _resolved_ as a parent and in the new sysfs layout it will just _be_ the
1223 parent in the devpath. If a device is requested by it's symlink, like all
1224 class devices in the new sysfs layout will look like, it gets automatically
1225 resolved and substituted with the real devpath and not the symlink path.
1228 A similar logic must be applied to _all_ sysfs users, including
1229 scripts, that search along parent devices in sysfs. The explicit use of
1230 the "device" link must be avoided. With the future sysfs layout all
1231 DEVPATH's will start with /devices/ and have a "subsystem" symlink poiting
1232 back to the "class" or the "bus". The layout of the parent devices in
1233 /devices is not necessarily expected to be stable across kernel releases and
1234 searching for parents by their subsystem should make sysfs users tolerant
1235 for changed parent chains.
1239 Prepare udev to work with the experimental kernel patch, that moves
1240 /sys/class devices to /sys/devices and /sys/block to /sys/class/block.
1242 Clarify BUS, ID, $id usage and fix $id behavior. This prepares for
1243 moving the class devices to /sys/devices.
1245 Thanks again to Marco for help finding a hopefully nice compromise
1246 to make %b simpler and working again.
1250 Complete removal of libsysfs, replaced by simple helper functions
1251 which are much simpler and a bit faster. The udev daemon operatesentirely
1252 on event parameters and does not use sysfs for simple rules anymore.
1253 Please report any new bugs/problems, that may be caused by this big
1254 change. They will be fixed immediately.
1256 The enumeration format character '%e' is deprecated and will be
1257 removed sometimes from a future udev version. It never worked correctly
1258 outside of udevstart, so we can't use it with the new parallel
1259 coldplug. A simple enumeration is as useless as the devfs naming
1260 scheme, just get rid of both if you still use it.
1262 MODALIAS and $modalias is not needed and will be removed from one of
1263 the next udev versions, replace it in all rules with ENV{MODALIAS} or
1264 the sysfs "modalias" value.
1266 Thanks a lot to Marco for all his help on finding and fixing bugs.
1270 Let scsi_id request libata drive serial numbers from page 0x80.
1272 Renamed etc/udev/persistent.rules to persistent-disk.rules and
1273 added /dev/disk/by-name/* for device mapper device names.
1275 Removed %e from the man page. It never worked reliably outside
1276 of udevstart and udevstart is no longer recommended to use.
1280 Symlinks are now exported to the event environment. Hopefully it's no
1281 longer needed to run udevinfo from an event process, like it was
1282 mentioned on the hotplug list:
1283 UDEV [1134776873.702967] add@/block/sdb
1286 DEVLINKS=/dev/disk/by-id/usb-IBM_Memory_Key_0218B301030027E8 /dev/disk/by-path/usb-0218B301030027E8:0:0:0
1290 Fix a problem if udevsend is used as the hotplug handler and tries to use
1291 syslog, which causes a "vc" event loop. 2.6.15 will make udevsend obsolete
1292 and this kind of problems will hopefully go away soon.
1296 All built-in logic to work around bad sysfs timing is removed with this
1297 version. The need to wait for sysfs files is almost fixed with a kernel
1298 version that doesn't work with this udev version anyway. Until we fix
1299 the timing of the "bus" link creation, the former integrated logic should
1300 be emulated by a rule placed before all other rules:
1301 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
1303 The option "udev_db" does no longer exist. All udev state will be in
1304 /$udev_root/.udev/ now, there is no longer an option to set this
1306 If the init script or something else used this value, just depend on
1307 this hardcoded path. But remember _all_content_ of this directory is
1308 still private to udev and can change at any time.
1310 Default location for rule sripts and helper programs is now: /lib/udev/.
1311 Everything that is not useful on the commandline should go into this
1312 directory. Some of the helpers in the extras folder are installed there
1313 now. The rules need to be changed, to find the helpers there.
1315 Also /lib/udev/devices is recommended as a directory where packages or
1316 the user can place real device nodes, which get copied over to /dev at
1317 every boot. This should replace the various solutions with custom config
1320 Udevsend does no longer start the udev daemon. This must be done with
1321 the init script that prepares /dev on tmpfs and creates the initial nodes,
1322 before starting the daemon.
1326 Silent a too verbose error logging for the old hotplug.d/ dev.d/
1329 The copy of klibc is removed. A systemwide installed version of klibc
1330 should be used to build a klibc udev now.
1334 NAME="" will not create any nodes, but execute RUN keys. To completely
1335 ignore an event the OPTION "ignore_device" should be used.
1337 After removal of the reorder queue, events with a TIMEOUT can be executed
1338 without any queuing now.
1342 Fixed bug in udevd, if inotify is not available. We depend on netlink
1343 uevents now, kernels without that event source will not work with that
1344 version of udev anymore.
1348 The rule parsing happens now in the daemon once at startup, all udev
1349 event processes inherit the already parsed rules from the daemon.
1350 It is shipped with SUSE10.0 and reduces heavily the system load at
1351 startup. The option to save precompiled rules and let the udev process
1352 pick the them up is removed, as it's no longer needed.
1354 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
1355 device. Libsysfs is changed to "translate" the requested link into the
1356 real device path, as it would happen with the hotplug event. Otherwise
1357 device removal and the udev database will not work.
1359 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
1362 A few improvements for vol_id, the filesytem probing code.
1366 Fix a stupid typo in extras/run_directory for "make install".
1368 scsi_id creates the temporary devnode now in /dev for usage with a
1369 non-writable /tmp directory.
1371 The uevent kernel socket buffer can carry app. 50.000 events now,
1372 let's see who can break this again. :)
1374 The upcoming kernel will have a new input driver core integration.
1375 Some class devices are now symlinks to the real device. libsysfs
1376 needs a fix for this to work correctly. Udevstart of older udev
1377 versions will _not_ create these devices!
1381 Fix a 'install' target in the Makefile, that prevents EXTRAS from
1386 A bunch of mostly trivial bugfixes. From now on no node name or
1387 symlink name can contain any character than plain whitelisted ascii
1388 characters or validated utf8 byte-streams. This is needed for the
1389 /dev/disk/by-label/* links, because we import untrusted data and
1390 export it to the filesystem.
1394 More bugfixes. If udevd was started from the kernel, we don't
1395 have stdin/stdout/stderr, which broke the forked tools in some
1400 Bugfix. udevstart event ordering was broken for a long time.
1401 The new run_program() uncovered it, because /dev/null was not
1402 available while we try to run external programs.
1403 Now udevstart should create it before we run anything.
1407 Minor bugfixes and some distro rules updates. If you don't have the
1408 persistent disk rules in /dev/disk/by-*/* on your distro, just
1409 grab it from here. :)
1413 We can use socket communication now to pass events from udev to
1415 RUN+="socket:/org/freedesktop/hal/udev_event"
1416 will pass the whole udev event to the HAL daemon without the need
1417 for a forked helper. (See ChangeLog for udevmonitor, as an example)
1421 Mostly bugfixes and see ChangeLog.
1423 The test for the existence of an environment value should be
1425 ENV{KEY}=="*" to ENV{KEY}=="?*"
1426 because "*" will not fail anymore, if the key does not exist or
1431 Bugfixes and a few tweaks described in the ChangeLog.
1435 Mostly a Bugfix release.
1437 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
1438 timing with custom rules.
1442 We changed the internal rule storage format. Our large rule files took
1443 2 MB of RAM, with the change we are down to 99kB.
1445 If the device-node has been created with default name and no symlink or
1446 options are to remenber, it is not longer stored in the udevdb. HAL will
1447 need to be updated to work correctly with that change.
1449 To overrride optimization flags, OPTFLAGS may be used now.
1457 Major changes happened with this release. The goal is to take over the
1458 complete kernel-event handling and provide a more efficient way to dispatch
1459 kernel events. Replacing most of the current shell script logic and the
1460 kernel forked helper with a netlink-daemon and a rule-based event handling.
1462 o udevd listens to netlink events now. The first valid netlink event
1463 will make udevd ignore any message from udevsend that contains a
1464 SEQNUM, to avoid duplicate events. The forked events can be disabled
1466 echo "" > /proc/sys/kernel/hotplug
1467 For full support, the broken input-subsytem needs to be fixed, not to
1468 bypass the driver core.
1470 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
1471 removed from udev itself and must be emulated by calling small
1472 helper binaries provided in the extras folder:
1473 make EXTRAS=extras/run_directory/
1474 will build udev_run_devd and udev_run_hotplugd, which can be called
1475 from a rule if needed:
1476 RUN+="/sbin/udev_run_hotplugd"
1477 The recommended way to handle this is to convert all the calls from
1478 the directories to explicit udev rules and get completely rid of the
1479 multiplexing. (To catch a ttyUSB event, you now no longer need to
1480 fork and exit 300 tty script instances you are not interested in, it
1481 is just one rule that matches exactly the device.)
1483 o udev handles now _all_ events not just events for class and block
1484 devices, this way it is possible to control the complete event
1485 behavior with udev rules. Especially useful for rules like:
1486 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
1488 o As used in the modalias rule, udev supports now textual
1489 substitution placeholder along with the usual format chars. This
1490 needs to be documented, for now it's only visible in udev_rules_parse.c.
1492 o The rule keys support now more operations. This is documented in the
1493 man page. It is possible to add values to list-keys like the SYMLINK
1494 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
1495 Also "final"-assignments are supported by using KEY:="value", which will
1496 prevent changing the key by any later rule.
1498 o kernel 2.6.12 has the "detached_state" attribute removed from
1499 sysfs, which was used to recognize sysfs population. We switched that
1500 to wait for the "bus" link, which is only available in kernels after 2.6.11.
1501 Running this udev version on older kernels may cause a short delay for
1504 o To provide infrastructure for persistent device naming, the id programs:
1505 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
1506 to export the probed data in environment key format:
1507 pim:~ # /sbin/ata_id --export /dev/hda
1508 ID_MODEL=HTS726060M9AT00
1509 ID_SERIAL=MRH401M4G6UM9B
1510 ID_REVISION=MH4OA6BA
1512 The following rules:
1513 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
1514 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
1517 kay@pim:~> tree /dev/disk
1520 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
1521 | `-- IBM-Memory_Key -> ../../sda
1523 | |-- swap -> ../../hda1
1524 | |-- date -> ../../sda1
1525 | `-- home -> ../../hda3
1527 |-- 2E08712B0870F2E7 -> ../../hda3
1528 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
1529 |-- E845-7A89 -> ../../sda1
1530 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
1532 The IMPORT= operation will import these keys in the environment and make
1533 it available for later PROGRAM= and RUN= executed programs. The keys are
1534 also stored in the udevdb and can be queried from there with one of the
1537 o A few binaries are silently added to the repository, which can be used
1538 to replay kernel events from initramfs instead of using coldplug. udevd
1539 can be instructed now to queue-up events while the stored events from
1540 initramfs are filled into the udevd-queue. This code is still under
1541 development and there is no documentation now besides the code itself.
1542 The additional binaries get compiled, but are not installed by default.
1544 o There is also a temporary fix for a performance problem where too many
1545 events happen in parallel and every event needs to parse the rules.
1546 udev can now read precompiled rules stored on disk. This is likely to be
1547 replaced by a more elegant solution in a future udev version.
1551 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
1552 Fix for libsysfs not to expect this file was added.
1556 All rules are applied now, but only the first matching rule with a NAME-key
1557 will be applied. All later rules with NAME-key are completely ignored. This
1558 way system supplied symlinks or permissions gets applied to user-defined
1562 Please check your rules setup, if you may need to add OPTIONS="last_rule"
1563 to some rules, to keep the old behavior.
1565 The rules are read on "remove"-events too. That makes is possible to match
1566 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
1567 instruct udev to ignore an event (OPTIONS="ignore_device").
1568 The new ACTION-key may be used to let a rule act only at a "remove"-event.
1570 The new RUN-key supports rule-based execution of programs after device-node
1571 handling. This is meant as a general replacement for the dev.d/-directories
1572 to give fine grained control over the execution of programs.
1574 The %s{}-sysfs format char replacement values are searched at any of the
1575 devices in the device chain now, not only at the class-device.
1577 We support log priority levels now. The value udev_log in udev.conf is used
1578 to determine what is printed to syslog. This makes it possible to
1579 run a version with compiled-in debug messages in a production environment
1580 which is sometimes needed to find a bug.
1581 It is still possible to supress the inclusion of _any_ syslog usage with
1582 USE_LOG=false to create the smallest possible binaries if needed.
1583 The configured udev_log value can be overridden with the environment variable
1588 Possible use of a system-wide klibc:
1589 make USE_KLIBC=true KLCC=/usr/bin/klcc all
1590 will link against an external klibc and our own version will be ignored.
1594 We support an unlimited count of symlinks now.
1596 If USE_STATIC=true is passed to a glibc build, we link statically and use
1597 a built-in userdb parser to resolve user and group names.
1599 The PLACE= key is gone. It can be replaced by an ID= for a long time, because
1600 we walk up the chain of physical devices to find a match.
1602 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
1603 easy to skip certain attribute matches without composing rules with weird
1604 character class negations like:
1605 KERNEL="[!s][!c][!d]*"
1606 this can now be replaced with:
1608 The current simple '=' is still supported, and should work as it does today,
1609 but existing rules should be converted if possible, to be better readable.
1611 We have new ENV{}== key now, to match against a maximum of 5 environment
1614 udevstart is its own binary again, because we don't need co carry this araound
1615 with every forked event.
~ianmdlvl / elogind.git / blob