Comment # 34 on bug 81644 from jackdachef@gmail.com

(In reply to comment #33)
> Created attachment 103895 [details]
> dmesg: X crashing while playing HTML5 video movie trailers on youtube, LLVM
> disabled, sb backend
> 
> so it at least doesn't seem to be caused by LLVM and/or vdpau,
> 
> must be something else in combination with the hardware acceleration

this was with hardware acceleration enabled