DF-0941 baseline panic (#0 unpatched kernel), captured from dfbsd-qemu/boot.log after
`sysctl hw.cpu_topology_phys_ids=0` as root. The very next page allocation traps:

---
Stopped at      vm_get_pg_color+0x76:   idivl   0x61ef6c(%rip),%eax
db>
---

The `idivl` instruction is the integer divide at sys/vm/vm_page.c:1225:
    physcale = PQ_L2_SIZE / cpu_topology_phys_ids;
Setting cpu_topology_phys_ids=0 makes the divisor 0, trapping in DDB.