Comment 4 for bug 570588

hmm, it seems to die in (or at least not proceed to) $KERNEL_IMG_CMD
possibly due to bashisms in setup_kernel_image() (i need to fix that)
that in turn seems to make the VM not exit properly...
can you try to change /bin/sh at the top of rootstock to /bin/bash and see if the segfault still shows up with the same commandline ?