Hello:

  My xserver crashed just after resuming from hibernation. I could get a backtrace of the crash from the core dump.

Debian testing, with unstable graphics stack:
linux 2.6.34
01:00.0 VGA compatible controller: ATI Technologies Inc Mobility Radeon HD 3600 Series
xserver-xorg-video-radeon 6.13.0
xserver-xorg-core 1.7.7
mesa 7.7.1-3
libdrm 2.4.18
Running KDE 4.4.3

#0  0x0000000000000001 in ?? ()                                                                                                                                                              
#1  0x00007f6fcbd81b63 in ?? () from /lib/libgcc_s.so.1                                                                                                                                      
#2  0x00007f6fcbd82479 in ?? () from /lib/libgcc_s.so.1                                                                                                                                      
#3  0x00007f6fcbd82608 in _Unwind_Backtrace () from /lib/libgcc_s.so.1                                                                                                                       
#4  0x00007f6fccb1fe7e in *__GI___backtrace (array=<value optimized out>, size=64) at ../sysdeps/x86_64/../ia64/backtrace.c:91                                                               
#5  0x000000000046a548 in xorg_backtrace () at ../../os/backtrace.c:45                                                                                                                       
#6  0x0000000000463169 in OsSigHandler (signo=11, sip=0x7fff060f0ab0, unused=0x7f6fcbd82608) at ../../os/osinit.c:139                                                                        
#7  <signal handler called>                                                                                                                                                                  
#8  radeon_bo_unref (bo=0x72006118000349) at ../../radeon/radeon_bo.c:69                                                                                                                     
#9  0x00007f6fcaa49456 in RADEONEXADestroyPixmap (pScreen=<value optimized out>, driverPriv=0x2c4b000) at ../../src/radeon_exa.c:464                                                         
#10 0x00007f6fca370a97 in exaDestroyPixmap_mixed (pPixmap=0x2c4a4a0) at ../../exa/exa_mixed.c:200                                                                                            
#11 0x00000000004c9d0c in damageDestroyPixmap (pPixmap=0x2c4a4a0) at ../../../miext/damage/damage.c:1747                                                                                     
#12 0x00007f6fcbb5f04d in XvDestroyPixmap (pPix=0x2c4a4a0) at ../../Xext/xvmain.c:381                                                                                                        
#13 0x00000000004ba598 in FreePicture (value=<value optimized out>, pid=<value optimized out>) at ../../render/picture.c:1572                                                                
#14 0x0000000000428813 in FreeClientResources (client=<value optimized out>) at ../../dix/resource.c:806                                                                                     
#15 0x000000000042a150 in CloseDownClient (client=0x28b07e0) at ../../dix/dispatch.c:3631                                                                                                    
#16 0x000000000042f808 in Dispatch () at ../../dix/dispatch.c:450                                                                                                                            
#17 0x0000000000425b4a in main (argc=8, argv=0x7d7ce8, envp=<value optimized out>) at ../../dix/main.c:285                                                                                   
                                                                                                                  
Feel free to request a full backtrace and regular Xorg log.

Regards,