Panic on 11.0-CURRENT when trying "kldload vmm"

22:13:~$ uname -a
FreeBSD mkushnir.mooo.com 11.0-CURRENT FreeBSD 11.0-CURRENT #3
r281432: Sun Apr 12 01:35:34 EEST 2015
root_at_:/work/obj/work/src.svn/sys/MAREK  amd64


Went kernel panic twice today when trying to load vmm.  Never seen
this before (the previous kernel was built out of r278973, Feb 19
2015, was doing well).  The panic is not reliable in the sense I could
not reproduce it at will just loading/unloading vmm.

I regularly work in my bhyve guests, sometimes swap between vmm and
vboxdrv, all my scenarios haven't changed from the previous Feb
kernel.  Except that I re-built my today panicking kernel extending
the MINIMAL config (including what I need) as opposed to the previous
one "reducing" GENERIC (excluding what I don't need).

Both today panic's back traces look identical. Attaching core.txt.1
(the latter one) and the output of "sysctl kern.conftxt". Let me know
if someone wants to debug it.

Thanks,
Markiyan.