Comment 11 for bug 481030

User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:2.0.0) Gecko/20100101 Firefox/4.0

I am using openSUSE 11.4 completely updated, KDE 4.6.2 from repo K:R:46 and LibreOffice from repo LibreOffice:/Stable.

My video card is identified by lspci as:
00:02.0 VGA compatible controller: Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller (rev 07)
and by X as: Intel(R) GM45.
In ~/.xsession-error sometimes I find:
OpenGL vendor string: Tungsten Graphics, Inc
OpenGL renderer string: Mesa DRI Mobile Intel® GM45 Express Chipset GEM 20100330 DEVELOPMENT
OpenGL version string: 2.1 Mesa 7.10
OpenGL shading language version string: 1.20
Driver: Intel
GPU class: i965
OpenGL version: 2.1
GLSL version: 1.20
Mesa version: 7.10
X server version: 1.9.3
Linux kernel version: 2.6.37
Direct rendering: yes
Requires strict binding: yes
GLSL shaders: yes
Texture NPOT support: yes

If I use the intel driver (from package xorg-x11-driver-video-7.6-52.4) sometimes the cpu goes to 100% and then X crashes. This event is quite rare and it is very difficult to reproduce and even to understand what induces it.

However using libreoffice I am able to induce probably the same crash, creating an empty presentation and then changing the zoom to at least 1200% using the slider or typing it after a double click on the zoom factor. The same happens using libreoffice draw (with the same zoom factor).
If I change the Xorg driver from intel to intellegacy (from package xorg-x11-driver-video-intel-legacy-2.9.1-8.1) the above procedure does not induce a crash of X.

The crash occurs also with a fresh user with all desktop effects disabled.

Before submitting this report, I asked in a forum to reproduce the bug

Reproducible: Always

Steps to Reproduce:
1. Start X using the intel driver on a GM45 video card
2. Launch libreoffice impress and create an empty presentation
3. Change zoom to at least 1200%
Actual Results:
X crashes and the login screen comes up

Expected Results:
X does not crash, as happens using intellegacy driver

In the Xorg.0.log file there is the following backtrace of the crash:

Backtrace:
[ 23062.651] 0: /usr/bin/Xorg (xorg_backtrace+0x28) [0x463678]
[ 23062.651] 1: /usr/bin/Xorg (0x400000+0x6ae89) [0x46ae89]
[ 23062.651] 2: /lib64/libc.so.6 (0x7f157045c000+0x32b30) [0x7f157048eb30]
[ 23062.652] 3: /usr/lib64/xorg/modules/drivers/intel_drv.so (0x7f156e87d000+0x12696) [0x7f156e88f696]
[ 23062.652] 4: /usr/lib64/xorg/modules/drivers/intel_drv.so (0x7f156e87d000+0x30614) [0x7f156e8ad614]
[ 23062.652] 5: /usr/bin/Xorg (0x400000+0xd8861) [0x4d8861]
[ 23062.652] 6: /usr/bin/Xorg (0x400000+0x2f6b1) [0x42f6b1]
[ 23062.652] 7: /usr/bin/Xorg (0x400000+0x25ace) [0x425ace]
[ 23062.652] 8: /lib64/libc.so.6 (__libc_start_main+0xfd) [0x7f157047abfd]
[ 23062.652] 9: /usr/bin/Xorg (0x400000+0x25679) [0x425679]
[ 23062.652] Segmentation fault at address 0x3f
[ 23062.652]
Fatal server error:
[ 23062.652] Caught signal 11 (Segmentation fault). Server aborting
[ 23062.652]
[ 23062.652]
Please consult the The X.Org Foundation support
         at http://wiki.x.org
 for help.
[ 23062.652] Please also check the log file at "/var/log/Xorg.0.log" for additional information.
[ 23062.652]