Compiz crashes Unity unexpectedly, no option for recovery

[Patrik B.]

Sometimes it occurs that my Unity session crashes just like that - no window decorations, no panel, but whatever was going on in the background continues, like music playback. Problem is though it cannot be restarted, since the option to kill the X server has been removed from 14.04.

I did only minor alterations to Compiz, eg. bound the zoom function to mouse buttons, added hotspots for expose to screen corners, changed the number of screens from the default 4 to 6 (+2 vertical), fade effects of windows, changed the drag button from ALT to Super,

yet it keeps freezing/hanging/crashing on a regular basis.

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: compiz-core 1:0.9.11+14.04.20140409-0ubuntu1
ProcVersionSignature: Ubuntu 3.13.0-24.46-generic 3.13.9
Uname: Linux 3.13.0-24-generic x86_64
.tmp.unity.support.test.0:

ApportVersion: 2.14.1-0ubuntu3
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
CurrentDesktop: Unity
Date: Sun May 4 12:58:07 2014
DistUpgraded: Fresh install
DistroCodename: trusty
DistroVariant: ubuntu
ExecutablePath: /usr/bin/compiz
GraphicsCard:
 Intel Corporation Core Processor Integrated Graphics Controller [8086:0046] (rev 02) (prog-if 00 [VGA controller])
   Subsystem: Toshiba America Info Systems Device [1179:fd10]
InstallationDate: Installed on 2014-04-28 (5 days ago)
InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Release amd64 (20140417)
MachineType: TOSHIBA Satellite L650
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.13.0-24-generic root=UUID=7d794905-c4a6-4f41-9752-49715657cbc2 ro quiet splash vt.handoff=7
SourcePackage: compiz
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 09/01/2010
dmi.bios.vendor: INSYDE
dmi.bios.version: 1.80
dmi.board.asset.tag: Base Board Asset Tag
dmi.board.name: Portable PC
dmi.board.vendor: TOSHIBA
dmi.board.version: Base Board Version
dmi.chassis.asset.tag: No Asset Tag
dmi.chassis.type: 10
dmi.chassis.vendor: Chassis Manufacturer
dmi.chassis.version: Chassis Version
dmi.modalias: dmi:bvnINSYDE:bvr1.80:bd09/01/2010:svnTOSHIBA:pnSatelliteL650:pvrPSK1EE-00Y007SK:rvnTOSHIBA:rnPortablePC:rvrBaseBoardVersion:cvnChassisManufacturer:ct10:cvrChassisVersion:
dmi.product.name: Satellite L650
dmi.product.version: PSK1EE-00Y007SK
dmi.sys.vendor: TOSHIBA
version.compiz: compiz 1:0.9.11+14.04.20140409-0ubuntu1
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.52-1
version.libgl1-mesa-dri: libgl1-mesa-dri 10.1.0-4ubuntu5
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 10.1.0-4ubuntu5
version.xserver-xorg-core: xserver-xorg-core 2:1.15.1-0ubuntu2
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.8.2-1ubuntu2
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.3.0-1ubuntu3
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.910-0ubuntu1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.10-1ubuntu2
xserver.bootTime: Sun May 4 12:54:32 2014
xserver.configfile: default
xserver.errors:

xserver.logfile: /var/log/Xorg.0.log
xserver.outputs:
 product id 560
 vendor LGD
xserver.version: 2:1.15.1-0ubuntu2