Reyk Floeter's paper explains more about the implementation of the userland side, vmd(8), including its privsep design and the use of pledge(2):<p><a href="http://bhyvecon.org/bhyvecon2016-Reyk.pdf" rel="nofollow">http://bhyvecon.org/bhyvecon2016-Reyk.pdf</a><p>OpenBSD's vmm(4) isn't related to FreeBSD bhyve, but Mike and Reyk were invited to talk about it in Tokyo. :-)