Comment 14 for bug 63031

I also get this on my new Thinkpad/Edgy 6/.10, however, the behaviour is as follows:

1)With kubuntu installed out of the box, the udev service is *not* set to start at boot. This strikes me as extremely odd, but that is definitely what the KDE control center (system->services) reported. In this configuration, the laptop works fine - it boots perfectly into X, and even USB keys are detected and automounted.

2)BUT, I needed to have my own udev rule (in /etc/udev/rules.d/10-local.rules), and so I set the udev service to start automatically at boot (again, using KDE's control center).

3)Now, when the system boots, I get dumped to a login prompt, and, when I log in, I get an endless stream of "/dev/null: permission denied" messages (fortunately, these stop when I hit Ctrl-C).

4)The workaround:
    (i) /etc/init.d/udev stop ;
        #By now, /dev/null has the right permissions.

    (ii) /etc/init.d/udev start ;
        #By now, the udev symlink which I initially wanted has been created.

    (iii) /etc/init.d/kdm restart
        #And X restarts contentedly.

---------------------

My system:

#udevtest /class/mem/null:

main: looking at device '/class/mem/null' from subsystem 'mem'
udev_rules_get_name: no node name set, will use kernel name 'null'
udev_db_get_device: no db file to read /dev/.udev/db/class@mem@null: No such file or directory
udev_node_add: creating device node '/dev/null', major = '1', minor = '3', mode = '0666', uid = '0', gid = '0'
main: run: 'socket:/org/freedesktop/hal/udev_event'
main: run: 'socket:/org/kernel/udev/monitor'

#The relevant bit of /var/log/udev (i.e. the ones referring to "null")

UEVENT[1167754351.369243] add@/class/mem/null
UDEV [1167754351.369243] add@/class/mem/mem
UDEV_LOG=3
ACTION=add
DEVPATH=/class/mem/mem
SUBSYSTEM=mem
SEQNUM=1536
MAJOR=1
MINOR=1
UDEVD_EVENT=1
DEVNAME=/dev/mem

UEVENT[1167754351.369249] add@/class/mem/port
UDEV [1167754351.369249] add@/class/mem/null
UDEV_LOG=3
ACTION=add
DEVPATH=/class/mem/null
SUBSYSTEM=mem
SEQNUM=1537
MAJOR=1
MINOR=3
UDEVD_EVENT=1
DEVNAME=/dev/null

Hope that helps; if there are other any tests I can do, let me know.