nvidia driver crashes in xinerama mode with displaylink

[Mike Brown]

single screen works fine. configuring 2 screens where a displaylink adapter is configured for screen 0 and nvidia is configured on screen 1 results in X segfaulting during load in the nvidia driver:

[ 1308.779] (II) NVIDIA(1): Setting mode "nvidia-auto-select"
[ 1308.801] Backtrace:
[ 1308.801] 0: /usr/bin/X (xorg_backtrace+0x26) [0x7f6169dc9886]
[ 1308.801] 1: /usr/bin/X (0x7f6169c41000+0x18c72a) [0x7f6169dcd72a]
[ 1308.801] 2: /lib/x86_64-linux-gnu/libpthread.so.0 (0x7f6168f67000+0xfcb0) [0x7f6168f76cb0]
[ 1308.801] 3: /usr/lib/x86_64-linux-gnu/xorg/extra-modules/nvidia_drv.so (0x7f61629bb000+0x4c329e) [0x7f6162e7e29e]
[ 1308.801] 4: /usr/lib/x86_64-linux-gnu/xorg/extra-modules/nvidia_drv.so (0x7f61629bb000+0x494d26) [0x7f6162e4fd26]
[ 1308.801] 5: /usr/lib/x86_64-linux-gnu/xorg/extra-modules/nvidia_drv.so (0x7f61629bb000+0x4a352a) [0x7f6162e5e52a]
[ 1308.801] 6: /usr/bin/X (AddScreen+0x171) [0x7f6169c8fbe1]
[ 1308.801] 7: /usr/bin/X (InitOutput+0x294) [0x7f6169ccf9c4]
[ 1308.801] 8: /usr/bin/X (0x7f6169c41000+0x3d5ed) [0x7f6169c7e5ed]
[ 1308.801] 9: /lib/x86_64-linux-gnu/libc.so.6 (__libc_start_main+0xed) [0x7f6167df876d]
[ 1308.801] 10: /usr/bin/X (0x7f6169c41000+0x3daad) [0x7f6169c7eaad]
[ 1308.801] Segmentation fault at address 0x8498
[ 1308.801] Caught signal 11 (Segmentation fault). Server aborting
[ 1308.801] Please consult the The X.Org Foundation support at http://wiki.x.org for help.
[ 1308.801] Please also check the log file at "/var/log/Xorg.0.log" for additional information.
[ 1308.803] ddxSigGiveUp: Closing log
[ 1308.803] Server terminated with error (1). Closing log file.

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: nvidia-current 295.40-0ubuntu1.2
ProcVersionSignature: Ubuntu 3.2.0-37.58-generic 3.2.35
Uname: Linux 3.2.0-37-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.0.1-0ubuntu17.1
Architecture: amd64
Date: Wed Feb 6 21:26:18 2013
DistroCodename: precise
DistroVariant: ubuntu
EcryptfsInUse: Yes
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Release amd64 (20120425)
MarkForUpload: True
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: nvidia-graphics-drivers
UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.