x server restarts unexpectedly after starting qtnx or xclock on Dell Precision T5500

[quantumstripper]

1) Release:
Ubuntu 11.10

2) Package:
qtnx 0.9-3ubuntu4

3) On running qtnx, I expect to see a qtnx window

4) The X server restarts when trying to run 'qtnx'. This also occurs when running the NX client that comes with the package from NoMachine. This happened occasionally in 11.04, but now it happens all the time when trying to run an NX client.

Neither dmesg nor /var/log/Xorg.*.log appear to give any indication that this occurs, so diagnostic information is limited. Please let me know if there is any additional diagnostic information I can collect.

5) Additional, possibly relevant information

Output from uname -a :
Linux walker 3.0.0-12-generic #20-Ubuntu SMP Fri Oct 7 14:56:25 UTC 2011 x86_64 x86_64 x86_64 GNU/Linux

Video card (with nVidia proprietary driver installed):
nVidia Corporation G98 [Quadro NVS 420]

ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: qtnx 0.9-3ubuntu4
ProcVersionSignature: Ubuntu 3.0.0-12.20-generic 3.0.4
Uname: Linux 3.0.0-12-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 1.23-0ubuntu3
Architecture: amd64
Date: Mon Oct 17 10:32:33 2011
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Release amd64 (20110427.1)
ProcEnviron:
 PATH=(custom, user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: qtnx
UpgradeStatus: Upgraded to oneiric on 2011-10-14 (2 days ago)

[quantumstripper (travis-obrien)]

I discovered that /var/log/syslog reports:
 Gdk-WARNING: gnome-session: Fatal IO error 11 (Resource temporarily unavailable) on X server :0.#012

On searching for bugs with similar text, I found Bug #583525, in which a commenter noted that the bug could be produced just with xclock. I also find that running xclock restarts the X server and reverts me to the login screen.

I have attempted to follow the instructions in http://wiki.ubuntu.com/DebuggingProgramCrash, but despite installing xserver-xorg-core-dbg, I don't have a version of xclock that was compiled with debugging symbols. I also couldn't manage to install a debug package for qtnx (following the instructions for a package for which ####-dbg does not exist). However, I have produced an strace of both qtnx and xclock.

[quantumstripper (travis-obrien)]

Adding an strace log for qtnx as well.

I should also note that starting a 'Recovery Console' instead of a normal session allows me to run qtnx without an X server restart.

[quantumstripper (travis-obrien)]

Since this affects xclock as well as qtnx, and the primary effect is that the X server restarts, I'm changing the affected package to xserver-xorg-core

[quantumstripper (travis-obrien)]

I have managed to get an Xorg backtrace for when the server dies after running 'xclock' and after running 'qtnx'. The server dies from a segmentation fault when dealing with fonts. The xclock gdb backtrace is attached, and the qtnx backtrace will be attached in the next comment.

[quantumstripper (travis-obrien)]

Adding backtrace for xserver segfault when running qtnx.

[quantumstripper (travis-obrien)]

Following a suggestion in Bug #683016, removing the package 'xfs' stops the segfaulting.

[penalvch (penalvch)]

quantumstripper, this bug was reported a while ago and there hasn't been any activity in it recently. We were wondering if this is still an issue? If so, could you please test for this with the latest development release of Ubuntu? ISO images are available from http://cdimage.ubuntu.com/daily-live/current/ .

If it remains an issue, could you please run the following command in the development release from a Terminal (Applications->Accessories->Terminal), as it will automatically gather and attach updated debug information to this report:

apport-collect -p xorg-server REPLACE-WITH-BUG-NUMBER

Please note, given that the information from the prior release is already available, doing this on a release prior to the development one would not be helpful.

Thank you for your understanding.

Helpful bug reporting tips:
https://wiki.ubuntu.com/ReportingBugs

[Launchpad Janitor (janitor)]

[Expired for xorg-server (Ubuntu) because there has been no activity for 60 days.]