recommend to replace a distro's udev installation with the upstream version.
Requirements:
- - Version 2.6.18 of the Linux kernel for reliable operation of this release of
- udev. The kernel may have a requirement on udev too, see Documentation/Changes
- in the kernel source tree for the actual dependency.
+ - Version 2.6.22 of the Linux kernel for reliable operation of this release of
+ udev. The kernel must not use the CONFIG_SYSFS_DEPRECATED* option.
- The kernel must have sysfs, unix domain sockets and networking enabled.
- (unix domain sockets (CONFIG_UNIX) as a loadable kernel module may work,
- but it does not make any sense - don't complain if anything goes wrong.)
+ Unix domain sockets (CONFIG_UNIX) as a loadable kernel module is not
+ supported.
- - The proc filesystem must be mounted on /proc, the sysfs filesystem must
- be mounted at /sys. No other locations are supported by udev.
+ - The proc filesystem must be mounted on /proc/, the sysfs filesystem must
+ be mounted at /sys/. No other locations are supported by udev.
+ - The system must have the following group names resolvable at udev startup:
+ disk, cdrom, floppy, tape, audio, video, lp, tty, dialout, kmem.
+ Especially in LDAP setups, it is required, that getgrnam() is able to resolve
+ these group names with only the rootfs mounted, and while no network is
+ available.
Operation:
- Udev creates and removes device nodes in /dev, based on events the kernel
+ Udev creates and removes device nodes in /dev/, based on events the kernel
sends out on device discovery or removal.
- - Very early in the boot process, the /dev directory should get a 'tmpfs'
+ - Very early in the boot process, the /dev/ directory should get a 'tmpfs'
filesystem mounted, which is populated from scratch by udev. Created nodes
or changed permissions will not survive a reboot, which is intentional.
- - The content of /lib/udev/devices directory which contains the nodes,
+ - The content of /lib/udev/devices/ directory which contains the nodes,
symlinks and directories, which are always expected to be in /dev, should
be copied over to the tmpfs mounted /dev, to provide the required nodes
to initialize udev and continue booting.
device node with the default kernel name, or the one specified by a
matching udev rule.
-
-Compile Options:
- DESTDIR
- Prefix of install target, used for package building.
- USE_LOG
- If set to 'true', udev is able to pass errors or debug information
- to syslog. This is very useful to see what udev is doing or not doing.
- It is enabled by default, don't expect any useful answer, if you
- need to hunt a bug, but you can't enable syslog.
- DEBUG
- If set to 'true', very verbose debugging messages will be compiled
- into the udev binaries. The actual level of debugging is specified
- in the udev config file.
- USE_SELINUX
- If set to 'true', udev will be built with SELinux support
- enabled. This is disabled by default.
- EXTRAS
- list of helper programs in extras/ to build.
- make EXTRAS="extras/cdrom_id extras/scsi_id extras/volume_id"
-
-
-Installation:
- - The install target intalls the udev binaries in the default locations,
- All binaries will be installed in /lib/udev or /sbin.
-
- - The default location for scripts and binaries that are called from
- rules is /lib/udev. Other packages who install udev rules, may use
- that directory too.
-
- - It is recommended to use the /lib/udev/devices/ directory to place
- device nodes and symlinks in, which are copied to /dev at every boot.
- That way, nodes for broken subsystems or devices which can't be
- detected automatically by the kernel, will always be available.
-
- - Default udev rules and persistent device naming rules are required by other
- software that depends on the data udev collects from the devices,
- and should be installed by default with every udev installation.
-
-Please direct any comment/question/concern to the linux-hotplug-devel mailing list at:
+Please direct any comment/question/concern to the linux-hotplug mailing list at:
linux-hotplug@vger.kernel.org