/*
 * DF-4841 trigger — NOT runnable on the audit guest (no LSI/3ware 9750 PCI
 * device exists; QEMU does not emulate one; tws is compiled into the kernel
 * with nothing attached).  This file documents the exact hardware-gated
 * trigger for a maintainer with a 9700-series controller.
 *
 * Defect: after a controller soft reset, the recovery path re-runs
 * tws_init_obfl_q() (tws_hdm.c:118-148, called from tws_reinit(),
 * tws_cam.c:1266, and from tws_init_ctlr, tws_hdm.c:111) to refill the
 * firmware's outbound free list.  But it only posts sense buffers whose
 * `posted` flag is false (tws_hdm.c:128), and nothing in the reset/recovery
 * path (tws_reset -> tws_reset_cb -> tws_reinit, tws_cam.c:1198-1266)
 * clears sc->sense_bufs[i].posted — all 256 were `posted == true` from
 * before the reset (they were sitting in the pre-reset queue; the flags are
 * only ever cleared at attach, tws.c:620, and on an OBFL overrun repost
 * failure, tws_cam.c:543).  The soft reset wipes the controller's copy of
 * the queue, so the "refill" is a no-op and the firmware is left with ZERO
 * response frames.
 *
 * Trigger (hardware present):
 *   1. Force the reset path: any controller error that reaches
 *      tws_reset() (tws_cam.c:1198) — e.g. a bus reset / controller
 *      fault / the unguarded re-entry of DF-4401 — or CAM freeze +
 *      recovery during heavy I/O.
 *   2. Observe the recovery complete (tws_reinit releases simq, turns
 *      interrupts back on, sends TWS_RESET_COMPLETE).
 *   3. Observe every subsequent command time out: the firmware cannot
 *      post a single response (no free frames in the outbound free
 *      list) — adapter and all I/O to it are dead until reboot.
 *      tws_init_connect()'s 60 s poll (TWS_POLL_TIMEOUT, tws.h:74)
 *      inside tws_reinit likewise cannot succeed once the queue it
 *      itself failed to refill is needed — the recovery defeats itself.
 *
 * Root-cause receipts:
 *   tws_hdm.c:127-144  while (i < tws_queue_depth) { if (!posted) post... }
 *   tws_cam.c:1262-1266 obfl_q_overrun=false; init_connect(); init_obfl_q();
 *   posted cleared only at tws.c:620 (attach) and tws_cam.c:543 (overrun).
 */
int df4841_trigger_placeholder;	/* see README.md */