Comment 2 for bug 1438770

StacktraceTop:
 rtHeapSimpleAllocBlock (pHeapInt=0x7f3b8f26b000, cb=64, uAlignment=32) at /build/buildd/virtualbox-4.3.26-dfsg/src/VBox/Runtime/common/alloc/heapsimple.cpp:498
 RTHeapSimpleAlloc (hHeap=<optimized out>, cb=<optimized out>, cbAlignment=<optimized out>) at /build/buildd/virtualbox-4.3.26-dfsg/src/VBox/Runtime/common/alloc/heapsimple.cpp:415
 HGSMIHeapBufferAlloc (pHeap=pHeap@entry=0x7f3b96925ee2, cbBuffer=cbBuffer@entry=56) at /build/buildd/virtualbox-4.3.26-dfsg/src/VBox/GuestHost/HGSMI/HGSMICommon.cpp:340
 HGSMIHeapAlloc (pHeap=0x7f3b96925ee2, cbData=32, u8Channel=<optimized out>, u16ChannelInfo=<optimized out>) at /build/buildd/virtualbox-4.3.26-dfsg/src/VBox/GuestHost/HGSMI/HGSMICommon.cpp:305
 VBoxHGSMIProcessDisplayInfo (pCtx=0x7f3b96925ee2, cDisplay=0, cOriginX=0, cOriginY=0, offStart=0, cbPitch=4096, cWidth=1024, cHeight=768, cBPP=32, fFlags=1) at /build/buildd/virtualbox-4.3.26-dfsg/src/VBox/Additions/common/VBoxVideo/Modesetting.cpp:257