X server crashes on user switching in Ubuntu 9.10

[cshadow]

I have a frequent xserver crashes when trying to switch users (either via GDM or CTRL-ALT-F7...).
Backtrace from Xorg.0.log.old alvasy ends up with:

Backtrace:
0: /usr/bin/X(xorg_backtrace+0x3b) [0x8133d6b]
1: /usr/bin/X(xf86SigHandler+0x55) [0x80c7d35]
2: [0xb76f9400]
3: /usr/bin/X [0x80f99f0]
4: /usr/lib/xorg/modules/drivers//nvidia_drv.so [0xb5eb55f7]
Saw signal 11.  Server aborting.

It happens with default 185.18 drivers, and also with 190.53.
Filed a bug on the launchpad, but for now no response:
https://bugs.launchpad.net/ubuntu/+s...er/+bug/502237

I need help in finding out if this bug is nvidia driver related or not and how to trace the issues from here.

[Dizzle7677]

Debugging the Xserver

http://www.x.org/wiki/Development/Do...erverDebugging

[cshadow]

Thx Dizzle7677, tried that and xserver crashed here:

Program received signal SIGUSR1, User defined signal 1.
0xb7704430 in __kernel_vsyscall ()
(gdb) c
Continuing.

Program received signal SIGSEGV, Segmentation fault.
0x080f95fc in xf86CursorSetCursor (pDev=0x93f5258, pScreen=0x927f458, pCurs=0x9c38928, x=0, 
    y=37) at ../../../../hw/xfree86/ramdac/xf86Cursor.c:324
324	../../../../hw/xfree86/ramdac/xf86Cursor.c: No such file or directory.
	in ../../../../hw/xfree86/ramdac/xf86Cursor.c
(gdb) c
Continuing.

Program received signal SIGSEGV, Segmentation fault.
0x080f95fc in xf86CursorSetCursor (pDev=0x93f5258, pScreen=0x927f458, pCurs=0x9c38928, x=0, 
    y=37) at ../../../../hw/xfree86/ramdac/xf86Cursor.c:324
324	in ../../../../hw/xfree86/ramdac/xf86Cursor.c
(gdb) c
Continuing.

Program terminated with signal SIGSEGV, Segmentation fault.
The program no longer exists.
(gdb)

Now, i guess this is an xorg issue?
And should be reported to the bugs.freedesktop.org?

EDIT: after a search it looks like this bug:
https://bugs.freedesktop.org/show_bug.cgi?id=25551
I also have 2 separate screens

[cshadow]

Sorry for bumping this but it seems this bug has been solved in xorg 1.8.1 :
http://lists.freedesktop.org/archive...il/006841.html
It's been driving me crazy since ubuntu 8.10, it has been introduced into xorg somewhere after version 1.5.2, so ubuntu 9.04,9.10,10.04 don't work for me. Now I'm running 10.04. with xorg 1.8.1 from xorg-edgers PPA (which has this oneliner patch built in) for a week and not a single crash. After months of torture with twinview I can finally use 2 screens again
It's interesting how my bug on launchpad got changed from xorg to nvidia-drivers despite evidence to the contrary:
https://bugs.edge.launchpad.net/ubun...80/+bug/502237
So, launchpad nvnews
Thanks guys for pointing me in the right direction, towards xorg debugging.