[cairo] Using cairo with image surface backend results hangs system

[Carl D. Blake]

I'm trying to use cairo with a DM8168 based system.  I want to be able
to use it with the framebuffer so I've set it up to use the image
surface backend.  I've mmaped the framebuffer to a memory location and
passed that as the data pointer to cairo_image_surface_create_for_data.
It appears to work for a while, but it always hangs the system at some
point when any drawing is being done (cairo_show_text or cairo_stroke).
I realize that cairo is drawing directly to the framebuffer, but I
didn't think this would be a problem.  Am I doing something wrong here?

Carl