Alan Jenkins
84629ccd85
Re: b99028c963 shrink struct udev_event
TEST 136: test multi matches 2
device '/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0' expecting node 'right'
==15011==
==15011== 7 bytes in 1 blocks are definitely lost in loss record 1 of 1
==15011== at 0x47F9AB8: malloc (vg_replace_malloc.c:207)
==15011== by 0x489CB5F: strdup (in /lib32/libc-2.7.so)
==15011== by 0x8050F40: udev_rules_apply_to_event (udev-rules.c:1973)
==15011== by 0x804A658: udev_event_execute_rules (udev-event.c:549)
==15011== by 0x805A636: main (test-udev.c:100)
add: ok
==15012==
==15012== 7 bytes in 1 blocks are definitely lost in loss record 1 of 1
==15012== at 0x47F1AB8: malloc (vg_replace_malloc.c:207)
==15012== by 0x4898B5F: strdup (in /lib32/libc-2.7.so)
==15012== by 0x8050F40: udev_rules_apply_to_event (udev-rules.c:1973)
==15012== by 0x804A9DF: udev_event_execute_rules (udev-event.c:658)
==15012== by 0x805A636: main (test-udev.c:100)
remove: ok
Signed-off-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
udev - userspace device management
For more information see the files in the docs/ directory.
Important Note:
Integrating udev in the system has complex dependencies and differs from distro
to distro. All major distros depend on udev these days and the system may not
work without a properly installed version. The upstream udev project does not
recommend to replace a distro's udev installation with the upstream version.
Requirements:
- Version 2.6.19 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.
- 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.)
- The proc filesystem must be mounted on /proc/, the sysfs filesystem must
be mounted at /sys/. No other locations are supported by udev.
Operation:
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'
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,
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.
- The old hotplug helper /sbin/hotplug should be disabled on bootup, before
actions like loading kernel modules are taken, which may cause a lot of
events.
- The udevd daemon must be started on bootup to receive netlink uevents
from the kernel driver core.
- All kernel events are matched against a set of specified rules in
/lib/udev/rules.d/ which make it possible to hook into the event
processing to load required kernel modules and setup devices. For all
devices the kernel exports a major/minor number, udev will create a
device node with the default kernel name, or the one specified by a
matching udev rule.
Please direct any comment/question/concern to the linux-hotplug mailing list at:
linux-hotplug@vger.kernel.org