Stock baseline kernel:
DragonFly dfbsd 6.5-DEVELOPMENT DragonFly 6.5-DEVELOPMENT #0: Thu Jul  2 06:02:54 UTC 2026     root@dfbsd:/usr/obj/usr/src/sys/X86_64_GENERIC  x86_64
(INVARIANTS enabled — stock dfbsd-qemu snapshot, clean)

Fix-validation kernel (built this run, in-guest):
DragonFly dfbsd 6.5-DEVELOPMENT DragonFly 6.5-DEVELOPMENT #1: Thu Sep  3 05:01:17 UTC 2026     root@dfbsd:/usr/obj/usr/src/sys/X86_64_GENERIC  x86_64
make nativekernel: BUILD_RC=0, make installkernel: INSTALL_RC=0

Guest storage root: hammer2 on vbd0s1d; vn driver in-kernel; KLD builds work
with SYSDIR=/usr/src/sys (sources present via with-src snapshot).