Xorg crashed with SIGABRT in OsAbort()

[zubozrout]

When switching from Intel to Nvidia on my Optimus laptop (Asus Zenbook UX32VD) on logout Xorg crashed.

Also, I am experiencing spontaneous freezes when using Nvidia GPU - display rendering can be resumed when switching from X11 to virtual terminal and back. Apparently I can still perform all actions but my screen keeps displaying the same from the point it freezes.
The second bug appears to be this: https://bugs.launchpad.net/ubuntu/+source/nvidia-prime/+bug/1220426 but it probably does not affect this crash.

ProblemType: Crash
DistroRelease: Ubuntu 14.10
Package: xserver-xorg-core 2:1.16.0-1ubuntu1
ProcVersionSignature: Ubuntu 3.16.0-14.20-generic 3.16.2
Uname: Linux 3.16.0-14-generic x86_64
NonfreeKernelModules: nvidia
.proc.driver.nvidia.gpus.0: Error: [Errno 21] je adresářem: '/proc/driver/nvidia/gpus/0'
.proc.driver.nvidia.registry: Binary: ""
.proc.driver.nvidia.version:
 NVRM version: NVIDIA UNIX x86_64 Kernel Module 331.89 Tue Jul 1 13:30:18 PDT 2014
 GCC version: gcc version 4.9.1 (Ubuntu 4.9.1-14ubuntu2)
.tmp.unity.support.test.0:

ApportVersion: 2.14.7-0ubuntu2
Architecture: amd64
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: compiz
CompositorUnredirectDriverBlacklist: '(nouveau|Intel).*Mesa 8.0'
CompositorUnredirectFSW: true
CrashCounter: 1
Date: Wed Sep 17 18:59:53 2014
DistUpgraded: 2014-09-01 07:53:46,252 DEBUG enabling apt cron job
DistroCodename: utopic
DistroVariant: ubuntu
ExecutablePath: /usr/bin/Xorg
GraphicsCard:
 Intel Corporation 3rd Gen Core processor Graphics Controller [8086:0166] (rev 09) (prog-if 00 [VGA controller])
   Subsystem: ASUSTeK Computer Inc. Device [1043:1507]
   Subsystem: ASUSTeK Computer Inc. GeForce GT 620M [1043:1507]
InstallationDate: Installed on 2014-08-04 (44 days ago)
InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Release amd64 (20140417)
MachineType: ASUSTeK COMPUTER INC. UX32VD
ProcCmdline: /usr/bin/X -core :0 -seat seat0 -auth /var/run/lightdm/root/:0 -nolisten tcp vt7 -novtswitch
ProcEnviron:

ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.16.0-14-generic root=UUID=22fda0b5-d94f-4ee6-97a8-40ee537b5002 ro quiet splash
Signal: 6
SourcePackage: nvidia-graphics-drivers
StacktraceTop:
 OsAbort ()
 ?? ()
 FatalError ()
 ?? ()
 __libc_start_main (main=0x7fafa2577680, argc=11, argv=0x7fff01b407f8, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fff01b407e8) at libc-start.c:287
Title: Xorg crashed with SIGABRT in OsAbort()
UpgradeStatus: Upgraded to utopic on 2014-09-01 (16 days ago)
UserGroups:

dmi.bios.date: 01/29/2013
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: UX32VD.214
dmi.board.asset.tag: ATN12345678901234567
dmi.board.name: UX32VD
dmi.board.vendor: ASUSTeK COMPUTER INC.
dmi.board.version: 1.0
dmi.chassis.asset.tag: No Asset Tag
dmi.chassis.type: 10
dmi.chassis.vendor: ASUSTeK COMPUTER INC.
dmi.chassis.version: 1.0
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrUX32VD.214:bd01/29/2013:svnASUSTeKCOMPUTERINC.:pnUX32VD:pvr1.0:rvnASUSTeKCOMPUTERINC.:rnUX32VD:rvr1.0:cvnASUSTeKCOMPUTERINC.:ct10:cvr1.0:
dmi.product.name: UX32VD
dmi.product.version: 1.0
dmi.sys.vendor: ASUSTeK COMPUTER INC.
version.compiz: compiz 1:0.9.12+14.10.20140812-0ubuntu1
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.56-1
version.libgl1-mesa-dri: libgl1-mesa-dri 10.2.6-1ubuntu3
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 10.2.6-1ubuntu3
version.nvidia-graphics-drivers: nvidia-graphics-drivers N/A
version.xserver-xorg-core: xserver-xorg-core 2:1.16.0-1ubuntu1
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.9.0-1ubuntu2
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.4.0-2ubuntu2
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.914-1~exp1ubuntu2
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.11-1ubuntu2
xserver.bootTime: Wed Sep 17 18:59:55 2014
xserver.configfile: /etc/X11/xorg.conf
xserver.errors:
 NVIDIA(0): Failed to initiate mode change.
 NVIDIA(0): Failed to complete mode change
xserver.logfile: /var/log/Xorg.0.log
xserver.outputs:
 product id 4931
 vendor CMN
xserver.version: 2:1.16.0-1ubuntu1

[Apport retracing service (apport)]

Thank you for taking the time to report this crash and helping to make this software better. This particular crash has already been reported and is a duplicate of bug #1338492, so is being marked as such. Please look at the other bug report to see if there is any missing information that you can provide, or to see if there is a workaround for the bug. Additionally, any further discussion regarding the bug should occur in the other report. Please continue to report any other bugs you may find.