bes2600: bus_reset on connection-loss storm to dodge assoc-comeback blackhole

When mac80211 declares connection loss against this AP (typically driven
by inactivity-deauth or beacon-loss), the userspace reauth that follows
sometimes enters a long blackhole: the AP responds to auth with success
but defers assoc with the 802.11v "assoc comeback" timer; ohm retries
faster than the comeback grants permission; the AP eventually fires an
unprotected deauth-reason-6 ("Class 2 frame received from non-
authenticated station"), and recovery only completes via cross-SSID or
cross-channel fallback. Receipts: ~86 s blackhole observed in the
phase-7 rep on 2026-05-07 02:42, with three subsequent BSSIDs returning
assoc comeback timeouts before reason-9 (STA_REQ_ASSOC_WITHOUT_AUTH)
fired. Documented in marfrit/besser:notes/phase4-2026-05-07.md.

When N=3 driver-side connection_loss decisions fire within a 60 s window
on the same vif, skip the ieee80211_connection_loss() path and trigger
the c5.2-introduced bes2600_chrdev_do_bus_reset() instead. The bus
reset removes and re-probes the chip; userspace re-associates with a
fresh chip state, dodging the AP's comeback-timer rejection cycle.

Predicted Phase 7 delta vs current baseline:
- api_connection_loss rate: unchanged (we don't address the trigger)
- conditional probability of >5 s blackhole given event: <= 30 %
- worst-case recovery: 86 s -> < 10 s

Contract pin: bes2600_chrdev_do_bus_reset(sbus_ops, sbus_priv) at
bes2600/bes_chardev.c:455, introduced by c5.2. The function is async-
returning: sbus_ops->bus_reset() schedules an SDIO rescan; the helper
waits up to 3 s for the remove() callback to clear sbus_priv, then
returns. Per-vif state is gone after this point, so the recover work
lives on bes2600_common (hw_priv) and uses the global bes2600_cdev for
the bus_reset call rather than dereferencing per-vif state.

Threshold (3 / 60 s) is well above the steady-state per-vif
connection_loss rate observed in the patch-A phase-7 rep (0.86/h under
sustained load), so a true storm is required to trip it.

Files touched:
- bes2600/bes2600.h: 3 counter fields on struct bes2600_vif, 1
  work_struct on struct bes2600_common, 3 prototypes
- bes2600/sta.c: 3 helpers + storm-account hook in
  bes2600_connection_loss_work + storm-init in bes2600_vif_setup +
  cancel_work_sync in the hw_priv shutdown path; #include bes_chardev.h
  was already pulled in by an earlier c-stack patch
- bes2600/main.c: INIT_WORK alongside other hw_priv work_structs
- bes2600/debug.c: ConnectionLossStormRecoveries seq_printf in the
  per-vif status seq_file output

The cw1200/cw1260 ancestor has no equivalent; this is a clean
addition. checkpatch.pl --no-tree --strict: clean (0/0/0).

Signed-off-by: Claude (noether) <claude@reauktion.de>
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

bes2600/bes2600.h

@@ -356,23 +356,15 @@ struct bes2600_common {
 	* Keeping in common structure for the time being. Will be moved to VIFF
 	* after the mechanism is clear */
 	u8				ba_tid_mask;
-	/*
+	int				ba_acc; /*TODO: Same as above */
-	 * Patch D: ba_lock removed.  Per-frame TX/RX hot-path bumped these
+	int				ba_cnt; /*TODO: Same as above */
-	 * counters under spin_lock_bh; the lock did not protect any
+	int				ba_cnt_rx; /*TODO: Same as above */
-	 * compound invariant that atomic ops can't satisfy.  Counters are
+	int				ba_acc_rx; /*TODO: Same as above */
-	 * now atomic_t; ba_armed gates the once-per-window mod_timer
+	int				ba_hist; /*TODO: Same as above */
-	 * arm via cmpxchg so concurrent TX/RX at a fresh window each
+	struct timer_list		ba_timer;/*TODO: Same as above */
-	 * try to claim the arm and exactly one succeeds.
+	spinlock_t			ba_lock; /*TODO: Same as above */
-	 */
+	bool				ba_ena; /*TODO: Same as above */
-	atomic_t			ba_acc;
+	struct work_struct              ba_work; /*TODO: Same as above */
-	atomic_t			ba_cnt;
-	atomic_t			ba_cnt_rx;
-	atomic_t			ba_acc_rx;
-	atomic_t			ba_armed;
-	int				ba_hist;
-	struct timer_list		ba_timer;
-	atomic_t			ba_ena;
-	struct work_struct              ba_work;
 	bool				is_BT_Present;
 	bool				is_go_thru_go_neg;
 	u8				conf_listen_interval;

bes2600/bes2600_sdio.c

@@ -29,7 +29,6 @@
 #include <linux/of_gpio.h>
 
 #include "bes2600.h"
-#include "bh.h"
 #include "sbus.h"
 #include "bes2600_plat.h"
 #include "bes2600_factory.h"
@@ -73,12 +72,10 @@ struct sbus_priv {
 	int rx_data_toggle;
 #endif
 #ifdef BES_SDIO_RX_MULTIPLE_ENABLE
-	/*
+	spinlock_t rx_queue_lock;
-	 * Patch C v3: rx_queue, rx_queue_lock, rx_work removed (no relay).
+	struct sk_buff_head rx_queue;
-	 * The bh thread now reads RX inline; the rx_buffer scratch area
-	 * stays.  Counters/timestamps stay for debugfs visibility.
-	 */
 	u8 *rx_buffer;
+	struct work_struct rx_work;
 	u32 rx_last_ctrl;
 	u32 rx_valid_ctrl;
 	u32 rx_total_ctrl_cnt;
@@ -415,19 +412,10 @@ static void bes2600_sdio_irq_handler(struct sdio_func *func)
 
 	bes_devel("%s called, fw_started:%d \n",
 			 __func__, self->fw_started);
-	/*
+	if (likely(self->fw_started && self->core)) {
-	 * Patch C v3: no more sdio_rx_work relay.  Wake the bh thread
+		queue_work(self->sdio_wq, &self->rx_work);
-	 * directly via self->irq_handler (bes2600_irq_handler in bh.c
-	 * which bumps bh_rx atomic + wakes bh_wq).  The bh thread will
-	 * then call sbus_ops->bus_rx_batch() to do the SDIO read inline.
-	 * Matches cw1200 mainline IRQ → bh-direct architecture.
-	 */
-	if (likely(self->fw_started && self->core && self->irq_handler)) {
-		spin_lock_irqsave(&self->lock, flags);
-		self->irq_handler(self->irq_priv);
-		spin_unlock_irqrestore(&self->lock, flags);
 		self->last_irq_timestamp = jiffies;
-	} else if (self->irq_handler) {
+	} else if(self->irq_handler) {
 		spin_lock_irqsave(&self->lock, flags);
 		self->irq_handler(self->irq_priv);
 		spin_unlock_irqrestore(&self->lock, flags);
@@ -824,15 +812,10 @@ static int bes2600_sdio_extract_packets(struct sbus_priv *self, u32 ctrl_reg, u8
 		skb_put(skb, packet_len);
 		memcpy(skb->data, &data[pos], packet_len);
 		bes_devel("%s, %d,%d\n", __func__, packet_len, pos);
+		spin_lock(&self->rx_queue_lock);
+		skb_queue_tail(&self->rx_queue, skb);
 		self->rx_data_cnt++;
-		/*
+		spin_unlock(&self->rx_queue_lock);
-		 * Patch C v3: deliver the SKB directly into the WSM/mac80211
-		 * stack from the bh thread.  No rx_queue, no inter-thread
-		 * handoff, no atomic_t needed on the counters that
-		 * wsm_release_tx_buffer touches — single-writer-from-bh is
-		 * preserved by construction.  See bh.c for the contract block.
-		 */
-		bes2600_bh_handle_rx_skb(self->core, skb);
 		packet_len = (packet_len + 3) & (~0x3);
 		pos += packet_len;
 		#ifdef BES_SDIO_OPTIMIZED_LEN
@@ -843,31 +826,17 @@ static int bes2600_sdio_extract_packets(struct sbus_priv *self, u32 ctrl_reg, u8
 	return 0;
 }
 
-/*
+static void sdio_rx_work(struct work_struct *work)
- * Patch C v3: bh thread calls this directly via sbus_ops->bus_rx_batch.
- * No more sdio_rx_work workqueue.  SDIO read sequence (lock →
- * read_ctrl → memcpy_fromio → packets_check → extract_packets) runs
- * inline in bh-thread context.  Each parsed SKB is delivered via
- * bes2600_bh_handle_rx_skb() from extract_packets — no rx_queue, no
- * second worker, no inter-thread handoff.
- *
- * Architecture matches cw1200 mainline.  Single-writer-from-bh
- * invariant on hw_bufs_used preserved by construction.
- *
- * Returns 0 on success (caller's bh outer loop decides whether to
- * continue), negative on bus read error.  On error: triggers
- * wifi_force_close (same as the old sdio_rx_work).
- */
-static int bes2600_sdio_read_rx_batch(struct sbus_priv *self)
 {
-	int ret = 0, again = 0, retry = 0, crc_retry = 0;
+	int ret, again = 0, retry = 0, crc_retry = 0;
 	u32 ctrl_reg = 0;
 	int total_len;
+	struct sbus_priv *self = container_of(work, struct sbus_priv, rx_work);
 	u8 *buf = self->rx_buffer;
 
 	/* don't read/write sdio when sdio error */
 	if (bes2600_chrdev_is_bus_error())
-		return 0;
+		return;
 
 	bes2600_gpio_wakeup_mcu(self, GPIO_WAKE_FLAG_SDIO_RX);
 
@@ -922,10 +891,6 @@ static int bes2600_sdio_read_rx_batch(struct sbus_priv *self)
 			goto failed;
 		}
 
-		/*
-		 * extract_packets parses the multi-RX buffer and calls
-		 * bes2600_bh_handle_rx_skb() per SKB.  No queueing.
-		 */
 		if ((ret = bes2600_sdio_extract_packets(self, ctrl_reg, buf))) {
 			bes_err("%s,%d error=%d\n", __func__, __LINE__, ret);
 			goto failed;
@@ -933,16 +898,22 @@ static int bes2600_sdio_read_rx_batch(struct sbus_priv *self)
 
 		ctrl_reg = 0;
 
+		if (likely(self->irq_handler)) {
+			self->irq_handler(self->irq_priv);
+		} else {
+			bes_err("%s,%d\n", __func__, __LINE__);
+			goto failed;
+		}
+
 	} while (again);
 
 	bes2600_gpio_allow_mcu_sleep(self, GPIO_WAKE_FLAG_SDIO_RX);
-	return 0;
+	return;
 
 failed:
 	bes2600_gpio_allow_mcu_sleep(self, GPIO_WAKE_FLAG_SDIO_RX);
 	bes2600_chrdev_wifi_force_close(self->core, false);
 	WARN_ON(1);
-	return -1;
 }
 
 static void sdio_scan_work(struct work_struct *work)
@@ -950,11 +921,26 @@ static void sdio_scan_work(struct work_struct *work)
 	bes_warn("%s: this function does nothing\n", __FUNCTION__);
 }
 
-/* Patch C v3: bes2600_sdio_pipe_read deleted.  bh thread reads the
+static void *bes2600_sdio_pipe_read(struct sbus_priv *self)
- * SDIO bus inline via bes2600_sdio_read_rx_batch (sbus_ops->bus_rx_batch).
+{
- * No rx_queue, no skb_dequeue, no relay.  bes2600_tx_loop_read remains
+	struct sk_buff *skb;
- * for the test bus error-fallback path but is now invoked at higher
+
- * level. */
+	if (bes2600_chrdev_is_bus_error()) {
+		return bes2600_tx_loop_read(self->core);
+	}
+
+	spin_lock(&self->rx_queue_lock);
+	skb = skb_dequeue(&self->rx_queue);
+	if (skb)
+		self->rx_proc_cnt++;
+	spin_unlock(&self->rx_queue_lock);
+	if (likely(self->fw_started == true &&
+		!bes2600_pwr_device_is_idle(self->core) &&
+		self->core->hw_bufs_used > 0))
+		if (!skb)
+			queue_work(self->sdio_wq, &self->rx_work);
+	return skb;
+}
 
 #endif
 
@@ -1210,14 +1196,7 @@ flush_previous:
 				}
 			} while (crc_retry <= 10);
 			sdio_release_host(self->func);
-			/*
+			queue_work(self->sdio_wq, &self->rx_work);
-			 * Patch C v3: wake the bh thread to check for any RX
-			 * that piggybacked on this TX window.  Bumps bh_rx
-			 * atomic; bh's wait_event will pick it up and call
-			 * sbus_ops->bus_rx_batch().
-			 */
-			if (likely(self->irq_handler))
-				self->irq_handler(self->irq_priv);
 			if (ret) {
 				bes_err("%s,%d err=%d,%d,%d\n", __func__, __LINE__, ret, scatters, cur_blk);
 				sdio_work_debug(self);
@@ -1268,11 +1247,12 @@ static int bes2600_sdio_misc_init(struct sbus_priv *self, struct bes2600_common
 	self->next_toggle = 0;
 #endif
 #ifdef BES_SDIO_RX_MULTIPLE_ENABLE
-	/* Patch C v3: rx_queue / rx_queue_lock removed (no relay). */
+	spin_lock_init(&self->rx_queue_lock);
+	skb_queue_head_init(&self->rx_queue);
 	self->rx_buffer = (u8 *)__get_dma_pages(GFP_KERNEL, get_order(1632 * BES_SDIO_RX_MULTIPLE_NUM));
 	if (!self->rx_buffer)
 		return -ENOMEM;
-	/* Patch C v3: sdio_rx_work removed; bh thread does the read. */
+	INIT_WORK(&self->rx_work, sdio_rx_work);
 #endif
 #ifdef BES_SDIO_TX_MULTIPLE_ENABLE
 	INIT_LIST_HEAD(&self->tx_bufferlist);
@@ -1601,15 +1581,22 @@ err:
 
 static void bes2600_sdio_empty_work(struct sbus_priv *self)
 {
+#ifdef BES_SDIO_RX_MULTIPLE_ENABLE
+	struct sk_buff *skb;
+#endif
 #ifdef BES_SDIO_TX_MULTIPLE_ENABLE
 	struct bes_sdio_tx_list_t *tx_buffer, *temp;
 #endif
 
 #ifdef BES_SDIO_RX_MULTIPLE_ENABLE
-	/*
+	cancel_work_sync(&self->rx_work);
-	 * Patch C v3: rx_work and rx_queue removed.  Counters still
+	while (1) {
-	 * reset for the next attach cycle.
+		skb = skb_dequeue(&self->rx_queue);
-	 */
+		if (skb)
+			dev_kfree_skb(skb);
+		else
+			break;
+	}
 	self->rx_last_ctrl = 0;
 	self->rx_total_ctrl_cnt = 0;
 	self->rx_continuous_ctrl_cnt = 0;
@@ -1877,8 +1864,7 @@ static struct sbus_ops bes2600_sdio_sbus_ops = {
 	.sbus_reg_write		= bes2600_sdio_reg_write,
 	.init			= bes2600_sdio_misc_init,
 #ifdef BES_SDIO_RX_MULTIPLE_ENABLE
-	/* Patch C v3: .pipe_read removed; bus_rx_batch replaces it. */
+	.pipe_read		= bes2600_sdio_pipe_read,
-	.bus_rx_batch		= bes2600_sdio_read_rx_batch,
 #endif
 #ifdef BES_SDIO_TX_MULTIPLE_ENABLE
 	.pipe_send		= bes2600_sdio_pipe_send,
@@ -1898,15 +1884,9 @@ static void bes2600_sdio_en_lp_cb(struct bes2600_common *hw_priv)
 	long unsigned int old_ts, new_ts;
 	struct sbus_priv *self = hw_priv->sbus_priv;
 
-	/*
-	 * Patch C v3: rx_work removed.  Wait for IRQ-timestamp activity
-	 * to settle by polling self->last_irq_timestamp via msleep
-	 * (best-effort).  The caller already knows the bh thread will
-	 * process pending bh_rx during its next wait_event round.
-	 */
 	do {
 		old_ts = self->last_irq_timestamp;
-		msleep(2);
+		flush_work(&self->rx_work);
 		new_ts = self->last_irq_timestamp;
 	} while(old_ts != new_ts);
 }
@@ -2264,12 +2244,8 @@ static int bes2600_sdio_suspend_noirq(struct device *dev)
 	if (func->num > 1)
 		return 0;
 
-	/*
+	if(self->core &&
-	 * Patch C v3: work_pending(&self->rx_work) check dropped (no
+	   (work_pending(&self->rx_work) || atomic_read(&self->core->bh_rx))) {
-	 * relay).  bh_rx atomic alone tells us whether the bh thread
-	 * has un-processed RX events queued.
-	 */
-	if (self->core && atomic_read(&self->core->bh_rx)) {
 		bes_devel("%s: Suspend interrupted.\n", __func__);
 		return -EAGAIN;
 	}

bes2600/bh.c

@@ -101,7 +101,7 @@ void bes2600_unregister_bh(struct bes2600_common *hw_priv)
 	coex_deinit_mode(hw_priv);
 #endif
 
-	atomic_inc(&hw_priv->bh_term);
+	atomic_add(1, &hw_priv->bh_term);
 	wake_up(&hw_priv->bh_wq);
 
 	flush_workqueue(hw_priv->bh_workqueue);
@@ -590,7 +590,7 @@ static int bes2600_bh(void *arg)
 			bes_devel("[BH] Device resume.\n");
 			atomic_set(&hw_priv->bh_suspend, BES2600_BH_RESUMED);
 			wake_up(&hw_priv->bh_evt_wq);
-			atomic_inc(&hw_priv->bh_rx);
+			atomic_add(1, &hw_priv->bh_rx);
 			continue;
 		}
 
@@ -758,9 +758,9 @@ tx:
 
 #if 0 /* count is not implemented */
 				if (ret > 1)
-					atomic_inc(&hw_priv->bh_tx);
+					atomic_add(1, &hw_priv->bh_tx);
 #else
-				atomic_inc(&hw_priv->bh_tx);
+				atomic_add(1, &hw_priv->bh_tx);
 #endif
 
 #if defined(CONFIG_BES2600_NON_POWER_OF_TWO_BLOCKSIZES)
@@ -958,119 +958,6 @@ static void bes2600_bh_parse_wakeup_event(struct bes2600_common *hw_priv, struct
 	}
 }
 
-/*
- * Direct-deliver an RX SKB into the WSM/mac80211 stack.
- *
- * Patch C v3 (no-relay architecture, matches cw1200): the bh thread
- * calls bes2600_sdio_read_rx_batch which calls
- * bes2600_sdio_extract_packets which calls THIS function per parsed
- * SKB.  No rx_queue, no sdio_rx_work, no inter-thread handoff.
- *
- * Single-writer-from-bh invariant on hw_priv->hw_bufs_used,
- * hw_priv->hw_bufs_used_vif[] and hw_priv->wsm_tx_pending[] is
- * preserved BY CONSTRUCTION — there is now only one writer (the bh
- * thread itself), same as cw1200's design.  No atomic_t conversion
- * needed.
- *
- * Contract:
- *   - process context, sleepable.  wsm_handle_rx (wsm.c, EXPORT_SYMBOL)
- *     acquires wsm_cmd.lock and may sleep on wait_event_timeout.
- *   - caller holds no bes2600 spinlock.  bes2600_sdio_unlock(self) is
- *     called inside read_rx_batch before extract_packets is invoked.
- *   - SKB ownership: function frees on every path (success + error).
- *   - No need to wake the bh thread on TX-confirm — we ARE the bh
- *     thread; tx_burst is signalled by returning *tx_out = 1 to the
- *     caller (bh_rx_helper), which propagates it to bh's outer loop.
- */
-int bes2600_bh_handle_rx_skb(struct bes2600_common *priv, struct sk_buff *skb)
-{
-	struct wsm_hdr *wsm;
-	size_t wsm_len;
-	u16 wsm_id;
-	u8 wsm_seq;
-	int tx = 0;
-	u32 confirm_label = 0x0;
-
-	if (!skb)
-		return 0;
-
-	wsm = (struct wsm_hdr *)skb->data;
-	wsm_len = __le16_to_cpu(wsm->len);
-	if (WARN_ON(wsm_len > skb->len)) {
-		bes_err("wsm_len err %d %d\n", (int)wsm_len, (int)skb->len);
-		dev_kfree_skb(skb);
-		return -1;
-	}
-
-	if (priv->wsm_enable_wsm_dumps)
-		print_hex_dump(KERN_DEBUG, "<-- ", DUMP_PREFIX_NONE, 16, 1,
-			       skb->data, wsm_len, false);
-
-	wsm_id  = __le16_to_cpu(wsm->id) & 0xFFF;
-	wsm_seq = (__le16_to_cpu(wsm->id) >> 13) & 7;
-	bes_devel("bes2600_bh_handle_rx_skb wsm_id:0x%04x seq:%d\n",
-		  wsm_id, wsm_seq);
-
-	skb_trim(skb, wsm_len);
-
-	if (wsm_id == 0x0800) {
-		wsm_handle_exception(priv,
-				     &skb->data[sizeof(*wsm)],
-				     wsm_len - sizeof(*wsm));
-		bes_err("wsm exception\n");
-		dev_kfree_skb(skb);
-		return -1;
-	} else if ((wsm_seq != priv->wsm_rx_seq[WSM_TXRX_SEQ_IDX(wsm_id)])) {
-		bes_err("seq error! %u. %u. 0x%x.", wsm_seq,
-			priv->wsm_rx_seq[WSM_TXRX_SEQ_IDX(wsm_id)], wsm_id);
-		dev_kfree_skb(skb);
-		return -1;
-	}
-
-	bes2600_bh_parse_wakeup_event(priv, skb);
-
-	priv->wsm_rx_seq[WSM_TXRX_SEQ_IDX(wsm_id)] = (wsm_seq + 1) & 7;
-
-	if (IS_DRIVER_TO_MCU_CMD(wsm_id))
-		confirm_label = __le32_to_cpu(((struct wsm_mcu_hdr *)wsm)->handle_label);
-
-	if (WSM_CONFIRM_CONDITION(wsm_id, confirm_label)) {
-		int rc = wsm_release_tx_buffer(priv, 1);
-		bes2600_bh_dec_pending_count(priv, WSM_TXRX_SEQ_IDX(wsm->id));
-
-		if (rc < 0) {
-			bes_err("wsm_release_tx_buffer failed: %d\n", rc);
-			dev_kfree_skb(skb);
-			return rc;
-		} else if (rc > 0) {
-			tx = 1;
-		}
-	}
-
-	/* wsm_handle_rx takes care of SKB lifetime: zeroes *skb_p if consumed. */
-	if (wsm_handle_rx(priv, wsm_id, wsm, &skb)) {
-		bes_err("wsm_handle_rx failed (id=0x%04x)\n", wsm_id);
-		if (skb)
-			dev_kfree_skb(skb);
-		return -1;
-	}
-
-	if (skb)
-		dev_kfree_skb(skb);
-
-	/*
-	 * Signal "tx side has new headroom" via atomic so the bh outer
-	 * loop's wait_event predicate notices on its next wait.  No
-	 * cross-thread wake needed because we are the bh thread; the
-	 * outer loop will pick this up after read_rx_batch returns.
-	 */
-	if (tx)
-		atomic_inc(&priv->bh_tx);
-
-	return 0;
-}
-EXPORT_SYMBOL(bes2600_bh_handle_rx_skb);
-
 static int bes2600_bh_rx_helper(struct bes2600_common *priv, int *tx)
 {
 	struct sk_buff *skb = NULL;
@@ -1082,18 +969,10 @@ static int bes2600_bh_rx_helper(struct bes2600_common *priv, int *tx)
 	u32 confirm_label = 0x0; /* wsm to mcu cmd cnfirm label */
 
 #if defined(BES_SDIO_RX_MULTIPLE_ENABLE)
-	/*
+	skb = (struct sk_buff *)priv->sbus_ops->pipe_read(priv->sbus_priv);
-	 * Patch C v3: the bh thread does the SDIO read inline via
+	if (!skb)
-	 * sbus_ops->bus_rx_batch.  bes2600_sdio_read_rx_batch reads the
+		return 0;
-	 * multi-RX coalesced frames out of the chip and delivers each
+	rx = 1; // always consider rx pipe not empty
-	 * one inline via bes2600_bh_handle_rx_skb (no rx_queue, no
-	 * pipe_read, no inter-thread handoff).  Return value: 0 on
-	 * success (bh outer loop will check whether to continue),
-	 * negative on read error.
-	 */
-	if (priv->sbus_ops->bus_rx_batch)
-		return priv->sbus_ops->bus_rx_batch(priv->sbus_priv);
-	return 0;
 #else
 	u32 ctrl_reg = 0;
 	size_t read_len = 0;
@@ -1255,7 +1134,7 @@ static int bes2600_bh_tx_helper(struct bes2600_common *hw_priv,
 	tx_len += 4;
 #endif
 
-	atomic_inc(&hw_priv->bh_tx);
+	atomic_add(1, &hw_priv->bh_tx);
 
 	tx_len = hw_priv->sbus_ops->align_size(
 		hw_priv->sbus_priv, tx_len);
@@ -1556,7 +1435,7 @@ static int bes2600_bh(void *arg)
 			bes_devel("[BH] Device resume.\n");
 			atomic_set(&hw_priv->bh_suspend, BES2600_BH_RESUMED);
 			wake_up(&hw_priv->bh_evt_wq);
-			atomic_inc(&hw_priv->bh_rx);
+			atomic_add(1, &hw_priv->bh_rx);
 			goto done;
 		}
 

bes2600/bh.h

@@ -39,15 +39,6 @@ int wsm_release_vif_tx_buffer(struct bes2600_common *hw_priv, int if_id,
 int bes2600_bh_sw_process(struct bes2600_common *hw_priv,
 			 struct wsm_tx_confirm *tx_confirm);
 
-/*
- * Direct-deliver an RX SKB into the WSM/mac80211 stack from the bh thread.
- * Called by bes2600_sdio_extract_packets per RX frame, no queueing.
- * Process context, sleepable, caller holds no bes2600 spinlock.
- * Function frees skb on every path. See bh.c for full contract.
- */
-int bes2600_bh_handle_rx_skb(struct bes2600_common *hw_priv,
-			     struct sk_buff *skb);
-
 void bes2600_bh_inc_pending_count(struct bes2600_common *hw_priv, int idx);
 void bes2600_bh_dec_pending_count(struct bes2600_common *hw_priv, int idx);
 

bes2600/debug.c

@@ -110,20 +110,17 @@ static int bes2600_status_show_common(struct seq_file *seq, void *v)
 	int ba_cnt, ba_acc, ba_cnt_rx, ba_acc_rx, ba_avg = 0, ba_avg_rx = 0;
 	bool ba_ena;
 
-	/*
+	spin_lock_bh(&hw_priv->ba_lock);
-	 * Patch D: ba_lock removed.  hw_priv->debug->ba_* are written only
+	ba_cnt = hw_priv->debug->ba_cnt;
-	 * by the timer callback (single writer); reading without a lock is
+	ba_acc = hw_priv->debug->ba_acc;
-	 * fine for stats.  ba_ena is atomic_t.
-	 */
-	ba_cnt    = hw_priv->debug->ba_cnt;
-	ba_acc    = hw_priv->debug->ba_acc;
 	ba_cnt_rx = hw_priv->debug->ba_cnt_rx;
 	ba_acc_rx = hw_priv->debug->ba_acc_rx;
-	ba_ena    = !!atomic_read(&hw_priv->ba_ena);
+	ba_ena = hw_priv->ba_ena;
 	if (ba_cnt)
 		ba_avg = ba_acc / ba_cnt;
 	if (ba_cnt_rx)
 		ba_avg_rx = ba_acc_rx / ba_cnt_rx;
+	spin_unlock_bh(&hw_priv->ba_lock);
 
 	seq_puts(seq,   "BES2600 Wireless LAN driver status\n");
 	seq_printf(seq, "Hardware:   %d.%d\n",

bes2600/itp.c

@@ -570,7 +570,7 @@ int bes2600_itp_get_tx(struct bes2600_common *priv, u8 **data,
 	*burst = 2;
 	atomic_set(&priv->bh_tx, 1);
 	ktime_get_ts(&itp->last_sent);
-	atomic_inc(&itp->awaiting_confirm);
+	atomic_add(1, &itp->awaiting_confirm);
 	spin_unlock_bh(&itp->tx_lock);
 	return 1;
 

bes2600/main.c

@@ -490,14 +490,13 @@ static struct ieee80211_hw *bes2600_init_common(size_t hw_priv_data_len)
 	INIT_LIST_HEAD(&hw_priv->event_queue);
 	INIT_WORK(&hw_priv->event_handler, bes2600_event_handler);
 	INIT_WORK(&hw_priv->ba_work, bes2600_ba_work);
-	/* Patch D: ba_lock removed; ba_acc/ba_cnt/etc are atomic_t. */
+	spin_lock_init(&hw_priv->ba_lock);
 	timer_setup(&hw_priv->ba_timer, bes2600_ba_timer, 0);
 
 	if (unlikely(bes2600_queue_stats_init(&hw_priv->tx_queue_stats,
 			WLAN_LINK_ID_MAX,
 			bes2600_skb_dtor,
 			hw_priv))) {
-		destroy_workqueue(hw_priv->workqueue);
 		ieee80211_free_hw(hw);
 		return NULL;
 	}
@@ -509,7 +508,6 @@ static struct ieee80211_hw *bes2600_init_common(size_t hw_priv_data_len)
 			for (; i > 0; i--)
 				bes2600_queue_deinit(&hw_priv->tx_queue[i - 1]);
 			bes2600_queue_stats_deinit(&hw_priv->tx_queue_stats);
-			destroy_workqueue(hw_priv->workqueue);
 			ieee80211_free_hw(hw);
 			return NULL;
 		}

bes2600/sbus.h

@@ -83,14 +83,6 @@ struct sbus_ops {
 	 * Returns 0 on success or a negative errno.
 	 */
 	int (*bus_reset)(struct sbus_priv *self);
-	/*
-	 * Read a batch of RX frames inline from the bus and deliver each
-	 * one via bes2600_bh_handle_rx_skb().  Called from the bh thread
-	 * (process context, sleepable).  Replaces the
-	 * sdio_rx_work + rx_queue + pipe_read relay (Patch C v3, 2026).
-	 * Returns 0 on success, negative on read error.
-	 */
-	int (*bus_rx_batch)(struct sbus_priv *self);
 };
 
 void bes2600_irq_handler(struct bes2600_common *priv);

bes2600/scan.c

@@ -257,21 +257,18 @@ int bes2600_hw_scan(struct ieee80211_hw *hw,
 
 	bes2600_pwr_set_busy_event(hw_priv, BES_PWR_LOCK_ON_SCAN);
 
-	/* will be unlocked in bes2600_scan_work() */
-	down(&hw_priv->scan.lock);
-	down(&hw_priv->conf_lock);
-
 	frame.skb = ieee80211_probereq_get(hw, priv->vif->addr, NULL, 0,
 		req->ie_len);
-	if (!frame.skb) {
+	if (!frame.skb)
-		up(&hw_priv->conf_lock);
-		up(&hw_priv->scan.lock);
 		return -ENOMEM;
-	}
 
 	if (req->ie_len)
 		skb_put_data(frame.skb, req->ie, req->ie_len);
 
+	/* will be unlocked in bes2600_scan_work() */
+	down(&hw_priv->scan.lock);
+	down(&hw_priv->conf_lock);
+
 	if (frame.skb) {
 		int ret;
 		//if (priv->if_id == 0)
@@ -289,9 +286,9 @@ int bes2600_hw_scan(struct ieee80211_hw *hw,
 		}
 #endif
 		if (ret) {
-			dev_kfree_skb(frame.skb);
 			up(&hw_priv->conf_lock);
 			up(&hw_priv->scan.lock);
+			dev_kfree_skb(frame.skb);
 			return ret;
 		}
 	}
@@ -321,10 +318,10 @@ int bes2600_hw_scan(struct ieee80211_hw *hw,
 		++hw_priv->scan.n_ssids;
 	}
 
+	up(&hw_priv->conf_lock);
+
 	if (frame.skb)
 		dev_kfree_skb(frame.skb);
-
-	up(&hw_priv->conf_lock);
 #ifdef WIFI_BT_COEXIST_EPTA_ENABLE
 	bwifi_change_current_status(hw_priv, BWIFI_STATUS_SCANNING);
 #endif
@@ -365,18 +362,14 @@ int bes2600_hw_sched_scan_start(struct ieee80211_hw *hw,
 	if (req->n_ssids > hw->wiphy->max_scan_ssids)
 		return -EINVAL;
 
+	frame.skb = ieee80211_probereq_get(hw, priv->vif->addr, NULL, 0,
+		req->ie_len);
+	if (!frame.skb)
+		return -ENOMEM;
+
 	/* will be unlocked in bes2600_scan_work() */
 	down(&hw_priv->scan.lock);
 	down(&hw_priv->conf_lock);
-
-	frame.skb = ieee80211_probereq_get(hw, priv->vif->addr, NULL, 0,
-		req->ie_len);
-	if (!frame.skb) {
-		up(&hw_priv->conf_lock);
-		up(&hw_priv->scan.lock);
-		return -ENOMEM;
-	}
-
 	if (frame.skb) {
 		int ret;
 		if (priv->if_id == 0)
@@ -387,9 +380,9 @@ int bes2600_hw_sched_scan_start(struct ieee80211_hw *hw,
 			ret = wsm_set_probe_responder(priv, true);
 		}
 		if (ret) {
-			dev_kfree_skb(frame.skb);
 			up(&hw_priv->conf_lock);
 			up(&hw_priv->scan.lock);
+			dev_kfree_skb(frame.skb);
 			return ret;
 		}
 	}
@@ -421,10 +414,10 @@ int bes2600_hw_sched_scan_start(struct ieee80211_hw *hw,
 		}
 	}
 
+	up(&hw_priv->conf_lock);
+
 	if (frame.skb)
 		dev_kfree_skb(frame.skb);
-
-	up(&hw_priv->conf_lock);
 	queue_work(hw_priv->workqueue, &hw_priv->scan.swork);
 	wiphy_warn(hw->wiphy, "<--[SCAN] Scheduled scan request.\n");
 	return 0;

bes2600/sta.c

@@ -2342,19 +2342,14 @@ void bes2600_join_work(struct work_struct *work)
 		//WARN_ON(wsm_reset(hw_priv, &reset, priv->if_id));
 		WARN_ON(wsm_set_block_ack_policy(hw_priv,
 			0, hw_priv->ba_tid_mask, priv->if_id));
-		/*
+		spin_lock_bh(&hw_priv->ba_lock);
-		 * Patch D: ba_lock removed.  Disconnect-reset clears the
+		hw_priv->ba_ena = false;
-		 * counters and the arm flag; producers racing here cannot
+		hw_priv->ba_cnt = 0;
-		 * cause harm — at worst they re-arm the timer and bump
+		hw_priv->ba_acc = 0;
-		 * counters that will be cleared on the next timer tick.
-		 */
-		atomic_set(&hw_priv->ba_ena, 0);
-		atomic_set(&hw_priv->ba_cnt, 0);
-		atomic_set(&hw_priv->ba_acc, 0);
 		hw_priv->ba_hist = 0;
-		atomic_set(&hw_priv->ba_cnt_rx, 0);
+		hw_priv->ba_cnt_rx = 0;
-		atomic_set(&hw_priv->ba_acc_rx, 0);
+		hw_priv->ba_acc_rx = 0;
-		atomic_set(&hw_priv->ba_armed, 0);
+		spin_unlock_bh(&hw_priv->ba_lock);
 
 		mgmt_policy.protectedMgmtEnable = 0;
 		mgmt_policy.unprotectedMgmtFramesAllowed = 1;
@@ -2634,11 +2629,10 @@ void bes2600_ba_work(struct work_struct *work)
 		return;*/
 
 	bes_devel("BA work****\n");
-	/*
+	spin_lock_bh(&hw_priv->ba_lock);
-	 * Patch D: ba_lock removed.  ba_tid_mask is u8 set once at init
+//	tx_ba_tid_mask = hw_priv->ba_ena ? hw_priv->ba_tid_mask : 0;
-	 * (main.c); reading it without a lock is fine.
-	 */
 	tx_ba_tid_mask = hw_priv->ba_tid_mask;
+	spin_unlock_bh(&hw_priv->ba_lock);
 
 	wsm_lock_tx(hw_priv);
 
@@ -2651,49 +2645,37 @@ void bes2600_ba_work(struct work_struct *work)
 void bes2600_ba_timer(struct timer_list *t)
 {
 	bool ba_ena;
-	int cnt, acc, cnt_rx, acc_rx;
 	struct bes2600_common *hw_priv = from_timer(hw_priv, t, ba_timer);
 
-	/*
+	spin_lock_bh(&hw_priv->ba_lock);
-	 * Patch D: ba_lock removed.  Snapshot atomic counters into locals
+	bes2600_debug_ba(hw_priv, hw_priv->ba_cnt, hw_priv->ba_acc,
-	 * for the predicate evaluation; producers may race incrementing
+			hw_priv->ba_cnt_rx, hw_priv->ba_acc_rx);
-	 * after the snapshot but the resulting decision is approximate
-	 * which the policy already tolerates (next timer tick re-evaluates).
-	 */
-	cnt    = atomic_read(&hw_priv->ba_cnt);
-	acc    = atomic_read(&hw_priv->ba_acc);
-	cnt_rx = atomic_read(&hw_priv->ba_cnt_rx);
-	acc_rx = atomic_read(&hw_priv->ba_acc_rx);
-
-	bes2600_debug_ba(hw_priv, cnt, acc, cnt_rx, acc_rx);
 
 	if (atomic_read(&hw_priv->scan.in_progress)) {
-		atomic_set(&hw_priv->ba_cnt, 0);
+		hw_priv->ba_cnt = 0;
-		atomic_set(&hw_priv->ba_acc, 0);
+		hw_priv->ba_acc = 0;
-		atomic_set(&hw_priv->ba_cnt_rx, 0);
+		hw_priv->ba_cnt_rx = 0;
-		atomic_set(&hw_priv->ba_acc_rx, 0);
+		hw_priv->ba_acc_rx = 0;
-		atomic_set(&hw_priv->ba_armed, 0);
+		goto skip_statistic_update;
-		return;
 	}
 
-	if (cnt >= BES2600_BLOCK_ACK_CNT &&
+	if (hw_priv->ba_cnt >= BES2600_BLOCK_ACK_CNT &&
-		(acc / cnt >= BES2600_BLOCK_ACK_THLD ||
+		(hw_priv->ba_acc / hw_priv->ba_cnt >= BES2600_BLOCK_ACK_THLD ||
-		(cnt_rx >= BES2600_BLOCK_ACK_CNT &&
+		(hw_priv->ba_cnt_rx >= BES2600_BLOCK_ACK_CNT &&
-		acc_rx / cnt_rx >=
+		hw_priv->ba_acc_rx / hw_priv->ba_cnt_rx >=
 			BES2600_BLOCK_ACK_THLD)))
 		ba_ena = true;
 	else
 		ba_ena = false;
 
-	atomic_set(&hw_priv->ba_cnt, 0);
+	hw_priv->ba_cnt = 0;
-	atomic_set(&hw_priv->ba_acc, 0);
+	hw_priv->ba_acc = 0;
-	atomic_set(&hw_priv->ba_cnt_rx, 0);
+	hw_priv->ba_cnt_rx = 0;
-	atomic_set(&hw_priv->ba_acc_rx, 0);
+	hw_priv->ba_acc_rx = 0;
-	atomic_set(&hw_priv->ba_armed, 0);
 
-	if (ba_ena != !!atomic_read(&hw_priv->ba_ena)) {
+	if (ba_ena != hw_priv->ba_ena) {
 		if (ba_ena || ++hw_priv->ba_hist >= BES2600_BLOCK_ACK_HIST) {
-			atomic_set(&hw_priv->ba_ena, ba_ena ? 1 : 0);
+			hw_priv->ba_ena = ba_ena;
 			hw_priv->ba_hist = 0;
 #if 0
 			bes_devel("[STA] %s block ACK:\n",
@@ -2703,6 +2685,9 @@ void bes2600_ba_timer(struct timer_list *t)
 		}
 	} else if (hw_priv->ba_hist)
 		--hw_priv->ba_hist;
+
+skip_statistic_update:
+	spin_unlock_bh(&hw_priv->ba_lock);
 }
 
 int bes2600_vif_setup(struct bes2600_vif *priv)

bes2600/txrx.c

@@ -995,18 +995,14 @@ bes2600_tx_h_ba_stat(struct bes2600_vif *priv,
 	if (!ieee80211_is_data(t->hdr->frame_control))
 		return;
 
-	/*
+	spin_lock_bh(&hw_priv->ba_lock);
-	 * Patch D: lock-free hot-path BA accounting.  atomic_inc + atomic_add
+	hw_priv->ba_acc += t->skb->len - t->hdrlen;
-	 * each per-frame; the once-per-window timer-arm uses cmpxchg on
+	if (!(hw_priv->ba_cnt_rx || hw_priv->ba_cnt)) {
-	 * ba_armed so concurrent TX/RX can't both try to set the timer and
-	 * we don't need cross-counter coherency on the ba_cnt/ba_cnt_rx pair.
-	 */
-	atomic_add(t->skb->len - t->hdrlen, &hw_priv->ba_acc);
-	atomic_inc(&hw_priv->ba_cnt);
-	if (atomic_cmpxchg(&hw_priv->ba_armed, 0, 1) == 0) {
 		mod_timer(&hw_priv->ba_timer,
 			jiffies + BES2600_BLOCK_ACK_INTERVAL);
 	}
+	hw_priv->ba_cnt++;
+	spin_unlock_bh(&hw_priv->ba_lock);
 }
 
 static int
@@ -1633,13 +1629,14 @@ bes2600_rx_h_ba_stat(struct bes2600_vif *priv,
 	if (!priv->setbssparams_done)
 		return;
 
-	/* Patch D: lock-free hot-path BA accounting; see TX side comment. */
+	spin_lock_bh(&hw_priv->ba_lock);
-	atomic_add(skb_len - hdrlen, &hw_priv->ba_acc_rx);
+	hw_priv->ba_acc_rx += skb_len - hdrlen;
-	atomic_inc(&hw_priv->ba_cnt_rx);
+	if (!(hw_priv->ba_cnt_rx || hw_priv->ba_cnt)) {
-	if (atomic_cmpxchg(&hw_priv->ba_armed, 0, 1) == 0) {
 		mod_timer(&hw_priv->ba_timer,
 			jiffies + BES2600_BLOCK_ACK_INTERVAL);
 	}
+	hw_priv->ba_cnt_rx++;
+	spin_unlock_bh(&hw_priv->ba_lock);
 }
 
 void bes2600_rx_cb(struct bes2600_vif *priv,