=== uname ===
DragonFly dfbsd 6.5-DEVELOPMENT DragonFly 6.5-DEVELOPMENT #1: Tue Sep  1 20:00:55 UTC 2026     root@dfbsd:/usr/obj/usr/src/sys/X86_64_GENERIC  x86_64
=== DF-2827 (e_phnum=0) on PATCHED kernel ===
trigger-fd3: fd=3, CKPT_THAW...
trigger-fd3: returned rc=-1 errno-pending (unexpected)
rc=0
=== DF-2826 fd3 variant on PATCHED kernel ===
trigger-fd3: fd=3, CKPT_THAW...
rc=127
=== DF-2826 fd0 variant on PATCHED kernel ===
trigger-fd0: ckpt on fd 0, CKPT_THAW...
rc=127
=== guest still up ===
 8:23PM  up 56 secs, 0 users, load averages: 0.11, 0.04, 0.01

--- dmesg tail after the three runs (patched kernel) ---
HAMMER2: INITIATE SPANs
swap low/high-water marks set to 41940/62910
pid 817 (stage2), uid 0: exited on signal 10 (core dumped)
pid 818 (stage2), uid 0: exited on signal 10 (core dumped)

INTERPRETATION
* DF-2827: sys_checkpoint returns a clean error (-1/EINVAL); no Fatal trap.
  Baseline: "Fatal trap 12: page fault while in kernel mode, fault VA 0x18".
* DF-2826 fd>=3: baseline "panic: vref: bad refcnt 00000000 1" inside
  elf_loadphdrs; patched: NO kernel panic - the process merely dies on the
  restored context (signal 10, the pre-existing userland restore anomaly
  documented in VERDICT.md), and the kernel continues (uptime ran after).
* DF-2826 fd<3: baseline "panic: fdrop: invalid f_count 0" at exit;
  patched: NO kernel panic, same benign userland death, kernel up.