# DF-5394 fixed-kernel validation (uname: #1 Sun Oct 4 01:09:43 UTC 2026)
# trigger identical to stock-kernel baseline (socket serial, zero-delay pairs)
$ ./vm.sh run_root 'kldunload xhci; 12x (kldload xhci; kldunload xhci); +20 more pairs'
CLEAN-RC=0
PAIR-0-OK
PAIR-1-OK
PAIR-2-OK
PAIR-3-OK
PAIR-4-OK
PAIR-5-OK
PAIR-6-OK
PAIR-7-OK
PAIR-8-OK
PAIR-9-OK
PAIR-10-OK
PAIR-11-OK
SURVIVED-ALL-12
--- ps -Ax | grep usbus (leaked kthreads): 0
--- dmesg | grep -c 'usbus0: detached': 13 (1 baseline + 12 pairs, every cycle full-dance)
HAMMER-20-DONE
--- after 32 total pairs: leaked usbus kthreads: 0, guest up, no panic

# serial console tail (clean cycles):
sbus0: detached
xhci0: detached
xhci0: <XHCI (generic) USB 3.0 controller> mem 0xfebd0000-0xfebd3fff irq 11 at device 3.0 on pci0
xhci0: 32 bytes context size, 64-bit DMA
usbus0 on xhci0
**WARNING** waiting for the following device to finish configuring:
  usb:	func=0xffffffff80a60880 arg=0xfffff80118fe0528
Giving up, interrupt routing is probably hosed
usbus0: 5.0Gbps Super Speed USB v3.0
ugen0.1: <0x1b36> at usbus0
uhub0: <0x1b36 XHCI root HUB, class 9/0, rev 3.00/1.00, addr 1> on usbus0
uhub0: 8 ports with 8 removable, self powered
uhub0: detached
ugen0.1: <0x1b36> at usbus0 (disconnected)
unknown: at usbus0, port 1, addr 1 (disconnected)
usbus0: detached
xhci0: detached