# DF-2967 - verification verdict

Status: **not_reproduced** | reproduced: 0 | impact: denial_of_service | confidence: likely

Mechanism line-confirmed; cannot execute on the stock kernel because the compile-time gate is absent: WDOG_DISABLE_ON_PANIC is not in X86_64_GENERIC (only LINT-family configs; no opt_wdog header exists in the guest kernel objdir), so the kern_shutdown.c panic hook that calls wdog_disable is compiled out - verified against the kernel config source and the built obj tree. The rest of the setup IS present on the guest (ichwd/amdsbwd modules exist and a watchdog registered: wdog: In-kernel automatic watchdog reset enabled at boot), and the self-deadlock path (callout_stop blocking then spin_lock(&wdogmtx) recursion) is consistent with the code. Availability-only. Fix (panicstr-safe wdog_disable using callout_stop_async) compiled into the fix-all kernel.

## Evidence pointers
config absence (X86_64_GENERIC has no WDOG_DISABLE_ON_PANIC); guest dmesg shows a registered watchdog; kern_wdog.c:96-177 ordering confirmed

## Kernel references
- sys/kern/kern_wdog.c:96
- sys/kern/kern_wdog.c:119
- sys/kern/kern_shutdown.c:860

## PoC changes vs the filing sketch
cannot be exercised without a custom kernel build; reasoned verification per contract

## Fix
recommendation: panic-safe wdog_disable (skip lock-dependent work when panicstr + callout_stop_async)

fix status: not_testable

compile-validated in fix-all kernel

Guest: DragonFly dfbsd 6.5-DEVELOPMENT DragonFly 6.5-DEVELOPMENT #0: Thu Jul  2 06:02:04 UTC 2026     root@dfbsd:/usr/obj/usr/src/sys/X86_64_GENERIC  x86_64

## Fix status (batch validation)
Applied with the 36 sibling fix.diffs of this batch in findings/poc/_batch41/all_fixes.patch; single in-guest `make -j6 nativekernel KERNCONF=X86_64_GENERIC` completed RC=0 with zero errors under -Werror (full log: findings/poc/_batch41/fix_build8.log). Behavior A/B intentionally skipped for this Info-tier item.