[gdm-list] Multi-seat issues with GDM 2.16

[Alexander Todorov <atodorov redhat com>]

Hello,
I'm experimenting with multi-seat configuration using DisplayLink devices as per
instructions on their wiki [1].

The displaylink kernel and Xorg drivers compiled and appear to work, the udev
scripts on the wiki needed slight change to make it work for me and only the
last part doesn't seem to work.

When the system boots in runlevel 3 I start /usr/sbin/gdm manually and execute
./usbseat.sh 2 to start X and gdm login screen on the terminal with ID 2.

The script uses the following commands:

/usr/bin/gdmdynamic -v -t 2 -s 1 -a "$1=/usr/bin/X :$1 -br -audit 0 -nolisten
tcp -novtswitch -sharevts -config $TMPFILE"
/usr/bin/gdmdynamic -v -r $1

Where the TMPFILE is a Xorg config file with proper grouping for display, mouse
and keyboard.

Xorg starts (I've tested it manually too). The mouse pointer is displayed using
the default theme for my distro (RHEL5.4), there's a blue circle around the
pointer for a while indicating that stuff is loading.

Then all of this shows only a black screen and the mouse pointer. It doesn't
show the login screen as one expects.

The pstree output looks ok:
     ├─gdm-binary───gdm-binary─┬─X
     │                         └─gdmgreeter

IIRC gdmgreeter is the application that shows the login screen.

The associated Xorg and gdm logs don't indicate any warnings or errors.

Does anyone have an idea how to debug this or why it's not working? I'm using
2.16 which is relatively old and multi-seat support is reported to work on older
versions.

[1] - http://libdlo.freedesktop.org/wiki/MultiSeatTerminal

Thanks,
Alexander.