#!/bin/sh
# DF-3236 baseline run reconstruction (see also panic.txt)
#
# Control (unprivileged, stock kernel):
#   $ /tmp/fhdevfs
#   [*] devfs fsid = ... boottime.tv_sec = ...
#   [*] fhopen(fid_ino=0x41414141, O_RDONLY): expect vn_lock(NULL) panic under root
#   [*] survived: fd=-1 errno=1 (Operation not permitted)     <-- SYSCAP gate
#
# Decisive baseline run (root, stock kernel #0 Jul 2 2026):
#   $ /root/df3236/fhdevfs
#   [*] real fid: ... (gen/fsid taken byte-exact from getfh("/dev/null"))
#   [*] fhopen(fid_ino=0x41414141, O_RDONLY): expect vn_lock(NULL) panic under root
#   <ssh session dies here - guest panicked>
#
# Serial console at that moment = panic.txt:
#   Fatal user address access from kernel mode from fhdevfs at ffffffff80647bad
#   Fatal trap 12: page fault while in kernel mode
#   fault virtual address   = 0x0
#   Stopped at  lockmgr_exclusive+0x5d: orl (%r14),%esi
#   current process = 922
#
# Patched kernel (fix.diff applied, kernel #1 Sep 9 2026):
#   $ /root/df3236/fhdevfs
#   [*] real fid: ...
#   [*] fhopen(fid_ino=0x41414141, O_RDONLY): expect vn_lock(NULL) panic under root
#   [*] survived: fd=-1 errno=2 (No such file or directory)
#   exit=1
#   $ uptime        <-- guest alive
echo "see header of this file; raw logs: panic.txt (baseline), fix_run.log (patched)"