#!/bin/sh
# DF-0019 run script — triggers the panic on the UNPATCHED kernel.
# Must be run as root on the DragonFlyBSD guest.
#
# The PoC:
#   1. Switches the current process to the bsd4 scheduler via usched_set(2).
#      (The default scheduler is "dfly" — the bsd4 code path is dormant
#       unless a process explicitly opts in.)
#   2. Writes kern.usched_bsd4.queue_checks=0 (root sysctl, no lower bound).
#   3. Forks CPU-bound children to force bsd4_chooseproc_locked_cache_coherent.
#
# On an UNPATCHED kernel: panic "chooseproc: at least the first lp was good"
#   (KASSERT at usched_bsd4.c:1548 trips because min_level_lwp is NULL —
#    the while loop at :1483 was skipped since checks(0) < queue_checks(0)
#    is false).
# On a FIXED kernel: sysctl returns EINVAL, PoC exits 0 cleanly.
#
# WARNING: panics an unpatched kernel. Disposable VM only.
set -e
cd "$(dirname "$0")"
./df0019 24