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
cc: DragonFly cc (GCC) 8.3 [DragonFly]  (this is the in-guest compiler for harness)
Guest PCI inventory: virtio-net + virtio-blk + PIIX3 only — NO bktr/bt848 device.
PoC mode: source-trace + userland harness (extracts the exact buggy arithmetic
from sys/dev/video/bktr/bktr_core.c). The kernel code path is not exercisable
on this guest because /dev/bktr0 does not exist (no bt848 in QEMU).