3 All built-in logic to work around bad sysfs timing is removed with this
4 version. The need to wait for sysfs files is almost fixed with a kernel
5 version that doesn't work with this udev version anyway. Until we fix
6 the timing of the "bus" link creation, the former integrated logic should
7 be emulated by a rule placed before all other rules:
8 ACTION=="add", DEVPATH=="/devices/*", ENV{PHYSDEVBUS}=="?*", WAIT_FOR_SYSFS="bus"
10 The option "udev_db" does no longer exist. All udev state will be in
11 /$udev_root/.udev/ now, there is no longer an option to set this
13 If the init script or something else used this value, just depend on
14 this hardcoded path. But remember _all_content_ of this directory is
15 still private to udev and can change at any time.
17 Default location for rule sripts and helper programs is now: /lib/udev/.
18 Everything that is not useful on the commandline should go into this
19 directory. Some of the helpers in the extras folder are installed there
20 now. The rules need to be changed, to find the helpers there.
22 Also /lib/udev/devices is recommended as a directory where packages or
23 the user can place real device nodes, which get copied over to /dev at
24 every boot. This should replace the various solutions with custom config
27 Udevsend does no longer start the udev daemon. This must be done with
28 the init script that prepares /dev on tmpfs and creates the initial nodes,
29 before starting the daemon.
33 Silent a too verbose error logging for the old hotplug.d/ dev.d/
36 The copy of klibc is removed. A systemwide installed version of klibc
37 should be used to build a klibc udev now.
41 NAME="" will not create any nodes, but execute RUN keys. To completely
42 ignore an event the OPTION "ignore_device" should be used.
44 After removal of the reorder queue, events with a TIMEOUT can be executed
45 without any queuing now.
49 Fixed bug in udevd, if inotify is not available. We depend on netlink
50 uevents now, kernels without that event source will not work with that
51 version of udev anymore.
55 The rule parsing happens now in the daemon once at startup, all udev
56 event processes inherit the already parsed rules from the daemon.
57 It is shipped with SUSE10.0 and reduces heavily the system load at
58 startup. The option to save precompiled rules and let the udev process
59 pick the them up is removed, as it's no longer needed.
61 Kernel 2.6.15 will have symlinks at /class/input pointing to the real
62 device. Libsysfs is changed to "translate" the requested link into the
63 real device path, as it would happen with the hotplug event. Otherwise
64 device removal and the udev database will not work.
66 Using 'make STRIPCMD=' will leave the binaries unstripped for debugging
69 A few improvements for vol_id, the filesytem probing code.
73 Fix a stupid typo in extras/run_directory for "make install".
75 scsi_id creates the temporary devnode now in /dev for usage with a
76 non-writable /tmp directory.
78 The uevent kernel socket buffer can carry app. 50.000 events now,
79 let's see who can break this again. :)
81 The upcoming kernel will have a new input driver core integration.
82 Some class devices are now symlinks to the real device. libsysfs
83 needs a fix for this to work correctly. Udevstart of older udev
84 versions will _not_ create these devices!
88 Fix a 'install' target in the Makefile, that prevents EXTRAS from
93 A bunch of mostly trivial bugfixes. From now on no node name or
94 symlink name can contain any character than plain whitelisted ascii
95 characters or validated utf8 byte-streams. This is needed for the
96 /dev/disk/by-label/* links, cause we import untrusted data and
97 export it to the filesystem.
101 More bugfixes. If udevd was started from the kernel, we don't
102 have stdin/stdout/stderr, which broke the forked tools in some
107 Bugfix. udevstart event ordering was broken for a long time.
108 The new run_program() uncovered it, cause /dev/null was not
109 available while we try to run external programs.
110 Now udevstart should create it before we run anything.
114 Minor bugfixes and some distro rules updates. If you don't have the
115 persistent disk rules in /dev/disk/by-*/* on your distro, just
116 grab it from here. :)
120 We can use socket communication now to pass events from udev to
122 RUN+="socket:/org/freedesktop/hal/udev_event"
123 will pass the whole udev event to the HAL daemon without the need
124 for a forked helper. (See ChangeLog for udevmonitor, as an example)
128 Mostly bugfixes and see ChangeLog.
130 The test for the existence of an environment value should be
132 ENV{KEY}=="*" to ENV{KEY}=="?*"
133 cause "*" will not fail anymore, if the key does not exist or
138 Bugfixes and a few tweaks described in the ChangeLog.
142 Mostly a Bugfix release.
144 Added WAIT_FOR_SYSFS="<attribute>" to be able to fight against the sysfs
145 timing with custom rules.
149 We changed the internal rule storage format. Our large rule files took
150 2 MB of RAM, with the change we are down to 99kB.
152 If the device-node has been created with default name and no symlink or
153 options are to remenber, it is not longer stored in the udevdb. HAL will
154 need to be updated to work correctly with that change.
156 To overrride optimization flags, OPTFLAGS may be used now.
164 Major changes happened with this release. The goal is to take over the
165 complete kernel-event handling and provide a more efficient way to dispatch
166 kernel events. Replacing most of the current shell script logic and the
167 kernel forked helper with a netlink-daemon and a rule-based event handling.
169 o udevd listens to netlink events now. The first valid netlink event
170 will make udevd ignore any message from udevsend that contains a
171 SEQNUM, to avoid duplicate events. The forked events can be disabled
173 echo "" > /proc/sys/kernel/hotplug
174 For full support, the broken input-subsytem needs to be fixed, not to
175 bypass the driver core.
177 o /etc/dev.d/ + /etc/hotplug.d/ directory multiplexing is completely
178 removed from udev itself and must be emulated by calling small
179 helper binaries provided in the extras folder:
180 make EXTRAS=extras/run_directory/
181 will build udev_run_devd and udev_run_hotplugd, which can be called
182 from a rule if needed:
183 RUN+="/sbin/udev_run_hotplugd"
184 The recommended way to handle this is to convert all the calls from
185 the directories to explicit udev rules and get completely rid of the
186 multiplexing. (To catch a ttyUSB event, you now no longer need to
187 fork and exit 300 tty script instances you are not interested in, it
188 is just one rule that matches exactly the device.)
190 o udev handles now _all_ events not just events for class and block
191 devices, this way it is possible to control the complete event
192 behavior with udev rules. Especially useful for rules like:
193 ACTION="add", DEVPATH="/devices/*", MODALIAS=="?*", RUN+="/sbin/modprobe $modalias"
195 o As used in the modalias rule, udev supports now textual
196 substitution placeholder along with the usual format chars. This
197 needs to be documented, for now it's only visible in udev_rules_parse.c.
199 o The rule keys support now more operations. This is documented in the
200 man page. It is possible to add values to list-keys like the SYMLINK
201 and RUN list with KEY+="value" and to clear the list by assigning KEY="".
202 Also "final"-assignments are supported by using KEY:="value", which will
203 prevent changing the key by any later rule.
205 o kernel 2.6.12 has the "detached_state" attribute removed from
206 sysfs, which was used to recognize sysfs population. We switched that
207 to wait for the "bus" link, which is only available in kernels after 2.6.11.
208 Running this udev version on older kernels may cause a short delay for
211 o To provide infrastructure for persistent device naming, the id programs:
212 scsi_id, vol_id (former udev_volume_id), and ata_id (new) are able now
213 to export the probed data in environment key format:
214 pim:~ # /sbin/ata_id --export /dev/hda
215 ID_MODEL=HTS726060M9AT00
216 ID_SERIAL=MRH401M4G6UM9B
220 KERNEL="hd*[!0-9]", IMPORT="/sbin/ata_id --export $tempnode"
221 KERNEL="hd*[!0-9]", ENV{ID_SERIAL}=="?*", SYMLINK+="disk/by-id/$env{ID_MODEL}_$env{ID_SERIAL}"
224 kay@pim:~> tree /dev/disk
227 | |-- HTS726060M9AT00_MRH401M4G6UM9B -> ../../hda
228 | `-- IBM-Memory_Key -> ../../sda
230 | |-- swap -> ../../hda1
231 | |-- date -> ../../sda1
232 | `-- home -> ../../hda3
234 |-- 2E08712B0870F2E7 -> ../../hda3
235 |-- 9352cfef-7687-47bc-a2a3-34cf136f72e1 -> ../../hda1
236 |-- E845-7A89 -> ../../sda1
237 `-- b2a61681-3812-4f13-a4ff-920d70604299 -> ../../hda2
239 The IMPORT= operation will import these keys in the environment and make
240 it available for later PROGRAM= and RUN= executed programs. The keys are
241 also stored in the udevdb and can be queried from there with one of the
244 o A few binaries are silently added to the repository, which can be used
245 to replay kernel events from initramfs instead of using coldplug. udevd
246 can be instructed now to queue-up events while the stored events from
247 initramfs are filled into the udevd-queue. This code is still under
248 development and there is no documentation now besides the code itself.
249 The additional binaries get compiled, but are not installed by default.
251 o There is also a temporary fix for a performance problem where too many
252 events happen in parallel and every event needs to parse the rules.
253 udev can now read precompiled rules stored on disk. This is likely to be
254 replaced by a more elegant solution in a future udev version.
258 With kernel version 2.6.12, the sysfs file "detached_state" was removed.
259 Fix for libsysfs not to expect this file was added.
263 All rules are applied now, but only the first matching rule with a NAME-key
264 will be applied. All later rules with NAME-key are completely ignored. This
265 way system supplied symlinks or permissions gets applied to user-defined
269 Please check your rules setup, if you may need to add OPTIONS="last_rule"
270 to some rules, to keep the old behavior.
272 The rules are read on "remove"-events too. That makes is possible to match
273 with keys that are available on remove (KERNEL, SUBSYSTEM, ID, ENV, ...) to
274 instruct udev to ignore an event (OPTIONS="ignore_device").
275 The new ACTION-key may be used to let a rule act only at a "remove"-event.
277 The new RUN-key supports rule-based execution of programs after device-node
278 handling. This is meant as a general replacement for the dev.d/-directories
279 to give fine grained control over the execution of programs.
281 The %s{}-sysfs format char replacement values are searched at any of the
282 devices in the device chain now, not only at the class-device.
284 We support log priority levels now. The value udev_log in udev.conf is used
285 to determine what is printed to syslog. This makes it possible to
286 run a version with compiled-in debug messages in a production environment
287 which is sometimes needed to find a bug.
288 It is still possible to supress the inclusion of _any_ syslog usage with
289 USE_LOG=false to create the smallest possible binaries if needed.
290 The configured udev_log value can be overridden with the environment variable
295 Possible use of a system-wide klibc:
296 make USE_KLIBC=true KLCC=/usr/bin/klcc all
297 will link against an external klibc and our own version will be ignored.
301 We support an unlimited count of symlinks now.
303 If USE_STATIC=true is passed to a glibc build, we link statically and use
304 a built-in userdb parser to resolve user and group names.
306 The PLACE= key is gone. It can be replaced by an ID= for a long time, cause
307 we walk up the chain of physical devices to find a match.
309 The KEY="<value>" format supports '=', '==', '!=,' , '+=' now. This makes it
310 easy to skip certain attribute matches without composing rules with weird
311 character class negations like:
312 KERNEL="[!s][!c][!d]*"
313 this can now be replaced with:
315 The current simple '=' is still supported, and should work as it does today,
316 but existing rules should be converted if possible, to be better readable.
318 We have new ENV{}== key now, to match against a maximum of 5 environment
321 udevstart is its own binary again, cause we don't need co carry this araound
322 with every forked event.