Created attachment 38113 [details]
X server log file showing crash/backtrace

My X server keeps crashing randomly when xscreensaver (which is set to cycle randomly between screen savers) runs.

Hardware: HP/Compaq dc5700
Video card: Intel Corporation 82Q963/Q965 Integrated Graphics Controller rev 2

I'm running dual-head, using the DVI output to run one screen and the VGA output to drive another. I use the RANDR extension to combine them into one virtual screen. Kernel is using KMS.

[    17.952] Build Operating System: Linux 2.6.34-gentoo-r2 x86_64 Gentoo
[    17.952] Current Operating System: Linux foo.example.org 2.6.35-gentoo-r1 #1 SMP Wed Aug 11 15:42:43 PDT 2010 x86_64
[    17.952] Kernel command line: dolvm real_root=/dev/sys/gentoo
[    17.952] Build Date: 23 July 2010  04:58:16PM
[    17.952]  
[    17.952] Current version of pixman: 0.18.4

Complete Xorg.0.log.old attached. It contains these errors and then a backtrace:

[ 11094.168] (EE) intel(0): [DRI2] DRI2SwapComplete: bad drawable
[ 11454.357] (EE) intel(0): [DRI2] DRI2SwapComplete: bad drawable
[ 16601.769] (EE) intel(0): [DRI2] DRI2SwapComplete: bad drawable
[ 17202.065] 
Backtrace:
[ 17202.065] 0: /usr/bin/X (xorg_backtrace+0x35) [0x487c21]
[ 17202.065] 1: /usr/bin/X (0x400000+0x562e5) [0x4562e5]
[ 17202.065] 2: /lib/libpthread.so.0 (0x7f0e2e1ec000+0xf410) [0x7f0e2e1fb410]
[ 17202.065] 3: /usr/bin/X (0x400000+0x5a92a) [0x45a92a]
[ 17202.065] 4: /usr/bin/X (LocalClient+0x2e) [0x451bd0]
[ 17202.065] 5: /usr/lib64/xorg/modules/extensions/libdri2.so (0x7f0e2be8a000+0x2f32) [0x7f0e2be8cf32]
[ 17202.065] 6: /usr/bin/X (0x400000+0x2d623) [0x42d623]
[ 17202.065] 7: /usr/bin/X (0x400000+0x24e9e) [0x424e9e]
[ 17202.065] 8: /lib/libc.so.6 (__libc_start_main+0xfd) [0x7f0e2c8dfd2d]
[ 17202.065] 9: /usr/bin/X (0x400000+0x24979) [0x424979]
[ 17202.065] Segmentation fault at address 0x28
[ 17202.065] 
Fatal server error:
[ 17202.065] Caught signal 11 (Segmentation fault). Server aborting

X server is run with -core option. gdb gives this stack trace:

#0  0x00007f0e2c8f3445 in raise () from /lib/libc.so.6
#1  0x00007f0e2c8f4860 in abort () from /lib/libc.so.6
#2  0x0000000000456bbd in OsAbort ()
#3  0x0000000000455192 in AbortServer ()
#4  0x0000000000455779 in FatalError ()
#5  0x0000000000456353 in OsSigHandler ()
#6  <signal handler called>
#7  0x000000000045a92a in _XSERVTransGetPeerAddr ()
#8  0x0000000000451bd0 in LocalClient ()
#9  0x00007f0e2be8cf32 in ?? () from /usr/lib64/xorg/modules/extensions/libdri2.so
#10 0x000000000042d623 in Dispatch ()
#11 0x0000000000424e9e in main ()