compiz crashed with SIGSEGV in nux::GpuDevice::GetGpuInfo()

[Luke12]

I was trying to test the guest session with Unity enabled. I have a ATI HD5470 graphics board. While logged in the guest session, Compiz and Unity would not behave properly (basically the unity overlay does look like black rectangles overlaid on top of the windows, quite randomly, not unlike the infamous old "black windows bug").

When I tried to disable the Unity plugin, Compiz and the guest session as a whole crashed.

ProblemType: Crash
DistroRelease: Ubuntu 11.04
Package: libnux-0.9-0 0.9.44-0ubuntu2
ProcVersionSignature: Ubuntu 2.6.38-8.42-generic 2.6.38.2
Uname: Linux 2.6.38-8-generic x86_64
NonfreeKernelModules: fglrx wl
Architecture: amd64
CrashCounter: 1
Date: Tue Apr 19 09:45:20 2011
ExecutablePath: /usr/bin/compiz
InstallationMedia: Ubuntu 10.04 LTS "Lucid Lynx" - Release amd64 (20100429)
ProcCmdline: compiz
ProcEnviron:
 LANG=it_IT.UTF-8
 SHELL=/bin/bash
SegvAnalysis:
 Segfault happened at: 0x7fe6f795c050 <_ZN3nux9GpuDevice10GetGpuInfoEv>: mov 0xc0(%rdi),%rax
 PC (0x7fe6f795c050) ok
 source "0xc0(%rdi)" (0x000000c0) not located in a known VMA region (needed readable region)!
 destination "%rax" ok
SegvReason: reading NULL VMA
Signal: 11
SourcePackage: nux
StacktraceTop:
 nux::GpuDevice::GetGpuInfo() () from /usr/lib/libnux-graphics-0.9.so.0
 nux::GpuDevice::CreateSystemCapableTexture() () from /usr/lib/libnux-graphics-0.9.so.0
 PanelMenuView::Refresh() () from /usr/lib/compiz/libunityshell.so
 PanelMenuView::OnActiveWindowChanged(_BamfView*, _BamfView*) () from /usr/lib/compiz/libunityshell.so
 g_closure_invoke () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
Title: compiz crashed with SIGSEGV in nux::GpuDevice::GetGpuInfo()
UpgradeStatus: Upgraded to natty on 2011-03-23 (26 days ago)
UserGroups:

[Apport retracing service (apport)]

Thank you for taking the time to report this crash and helping to make Ubuntu better. This particular crash has already been reported and is a duplicate of bug #761368, 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.