=== PATCHED KERNEL (hpfs.ko sha256 8846085...) variant validation ===
Patched module: /boot/kernel/hpfs.ko (44160 bytes, built from /usr/src/sys/vfs/hpfs with fix.diff applied)

--- Variant A (de_reclen=0xFFFF OOB) ---
[image: df0927_oob.img mounted at /mnt/df0927]
$ stat /mnt/df0927/zzz
stat: /mnt/df0927/zzz: stat: Invalid argument
STAT_EXIT=1
[status: up; no panic]
[dmesg: hpfs_validateparent: corrupt dirblk]

--- Variant B (de_reclen=0 spin) ---
[image: df0927_hang1.img]
$ stat /mnt/df0927/zzz
stat: /mnt/df0927/zzz: stat: Invalid argument
STAT_EXIT=1
[status: up; no hang]
[dmesg: hpfs_validateparent: corrupt dirblk]

--- Variant C (D0<->D1 DE_DOWN cycle) ---
[image: df0927_cycle.img]
$ stat /mnt/df0927/zzz
stat: /mnt/df0927/zzz: stat: Invalid argument
STAT_EXIT=1
[status: up; no hang]
[dmesg: hpfs_validateparent: corrupt dirblk / hpfs_validateparent: too deep at lsn 0x40]