VIMAGE must still be experimental. I have 10.0-RELEASE-p7 with a custom kernel with options VIMAGE and when stopping a jail:
Code:
Freed UMA keg (udp_inpcb) was not empty (60 items). Lost 6 pages of memory.
Freed UMA keg (udpcb) was not empty (251 items). Lost 1 pages of memory.
hhook_vnet_uninit: hhook_head type=1, id=1 cleanup required
hhook_vnet_uninit: hhook_head type=1, id=0 cleanup required