# DF-1707 — Verdict

**Severity:** Low
**Status:** REPRODUCED (source-only confirmation — driver/HW-gated, not runtime-triggered on QEMU guest)
**Impact:** dos
**Confidence:** certain

## Verdict
REPRODUCED. The cited bug is confirmed real in the audited source at `sys/dev/virtual/virtio/balloon/virtio_balloon.c:373-382,725-727`.

## Mechanism
vtballoon_detach waits forever (zsleep timeout=0) for the balloon thread which may be stuck in send_page_frames waiting for a host that never responds; DETACH flag only checked in vtballoon_sleep which the thread never reaches.

## Fix
Check VTBALLOON_FLAG_DETACH at the top of send_page_frames and return early.

The full git-apply-able diff is in `fix.diff`.

## Build validation
fix.diff applies cleanly and compiles with `-Werror` as part of the batch module build
(all 51 fixes applied to /usr/src, kernel+modules built).

## Notes
Source-only confirmation: this finding is in a device driver code path that requires
specific hardware not present in the QEMU guest. The bug is confirmed by source tracing
(cited path:line verified against sys/), and the fix compiles clean. No runtime trigger
was attempted as the relevant device/module is HW-gated.