OpenGL issues - glxgears failure or segfault

[Riccardo Mottola <riccardo.mottola%libero.it@localhost>]

Hi,

I traced down my WebGL problems to core OpenGL issues.
If I run glxgears I get bad results.
The display does not show rotating gears but either two images vibrating 
between (strobo-effect like) or even just one frozen image.

Sometimes I get a crash, like this:
$ glxgears
Running synchronized to the vertical refresh.  The framerate should be
approximately the same as the monitor refresh rate.
i965: Failed to submit batchbuffer: Input/output error


This is on a laptop with integrated Iron Lake graphics running NetBSD/amd64.

I just did check dmesg to type out the details here, but see it flooded 
with this errors:

[   128.377135] 0001327c :  00000000
[   128.377135] 00013280 :  7a006002
[   128.377135] 00013284 :  00024104
[   128.377135] 00013288 :  00000000
[   128.377135] 0001328c :  00000000
[   128.377135] 00013290 :  7a006002
[   128.377135] 00013294 :  00024184
[   128.377135] 00013298 :  00000000
[   128.377135] 0001329c :  00000000
[   128.377135] 000132a0 :  7a006002
[   128.377135] 000132a4 :  00024204
[   128.377135] 000132a8 :  00000000
[   128.377135] 000132ac :  00000000
[   128.377135] 000132b0 :  7a006002
[   128.377135] 000132b4 :  00024284
[   128.377135] 000132b8 :  00000000
[   128.377135] 000132bc :  00000000
[   128.377135] 000132c0 :  7a006002
[   128.387142] 000132c4 :  00024304
[   128.387142] 000132c8 :  00000000
[   128.387142] 000132cc :  00000000
[   128.387142] 000132d0 :  7a005502
[   128.387142] 000132d4 :  00024004
[   128.387142] 000132d8 :  fffff204
[   128.387142] 000132dc :  00000000
[   128.387142] 000132e0 :  02000022
[   128.387142] 000132e4 :  00000000
[   128.387142] 000132e8 :  18800180
[   128.387142] 000132ec :  1f9d9000
[   128.387142] 000132f0 :  02000000
[   128.387142] 000132f4 :  00000000
[   128.387142] 000132f8 :  7a005402
[   128.387142] 000132fc :  00024004
[   128.387142] 00013300 :  fffff205
[   128.387142] 00013304 :  00000000
[   128.387142] 00013308 :  7a006002
[   128.387142] 0001330c :  00024084
[   128.387142] 00013310 :  00000000
[   128.387142] 00013314 :  00000000
[   128.387142] 00013318 :  7a006002
[   128.387142] 0001331c :  000
[  8185.721137] kern error: 
[drm:(/usr/src/sys/external/bsd/drm2/dist/drm/i915/intel_sprite.c:132)intel_pipe_update_start] 
*ERROR* Potential atomic update failure on pipe A: -35
[ 24956.434454] kern error: 
[drm:(/usr/src/sys/external/bsd/drm2/dist/drm/i915/intel_sprite.c:132)intel_pipe_update_start] 
*ERROR* Potential atomic update failure on pipe A: -35
[ 25038.667770] kern error: 
[drm:(/usr/src/sys/external/bsd/drm2/dist/drm/i915/intel_sprite.c:132)intel_pipe_update_start] 
*ERROR* Potential atomic update failure on pipe A: -35
[ 25866.454467] kern error: 
[drm:(/usr/src/sys/external/bsd/drm2/dist/drm/i915/intel_sprite.c:132)intel_pipe_update_start] 
*ERROR* Potential atomic update failure on pipe A: -35

now, If I rerun glxgears, I get a segfault:
$ glxgears
Running synchronized to the vertical refresh.  The framerate should be
approximately the same as the monitor refresh rate.
[1]   Segmentation fault (core dumped) glxgears

Thread 1 "" received signal SIGSEGV, Segmentation fault.
0x0000717487fe5850 in brw_workaround_depthstencil_alignment () from 
/usr/X11R7/lib/modules/dri/i965_dri.so
(gdb) bt
#0  0x0000717487fe5850 in brw_workaround_depthstencil_alignment () from 
/usr/X11R7/lib/modules/dri/i965_dri.so
#1  0x0000717487fa34d5 in ?? () from /usr/X11R7/lib/modules/dri/i965_dri.so
#2  0x000000017f001f8a in draw ()
#3  0x000000017f00353d in main ()

doesn't look nice!!

Riccardo