We have three more fixes:

* AP_VLAN tailroom calculation fix, the bug leads to warnings
    along with dropped packets
  * NAPI context issue, calling napi_gro_receive() from a timer
    (obviously) can lead to crashes
  * remain-on-channel combining leads to dropped requests and not
    being able to finish certain operations, so remove it
 -----BEGIN PGP SIGNATURE-----
 
 iQIcBAABCAAGBQJVZB7ZAAoJEDBSmw7B7bqr/qkQAKW5RHFfo8TtjUB7pl/iWqc3
 /gyym9tisy4hc7OOr8BDTQdUvqzY4fRMhuTAvjPLXCqdV2Isz1IetiogiJRMglNs
 3v83QkmEI8vMQ3lP6Y+2Hnz9tw1zNaVXHGwIKPjk9YLrzsBV0AJoGqn8qo4OBfWl
 JjkHLM6/0PVDy5UDF95cRyM6+L0XJdPdVS/YRLslp5Tda8fgTbH+dMwLnzjQZbIu
 ZanFpAuRxx35g/Zg6vAsRhlva/zrucphteaiJGAa6a3NgH9Z4tDlGHRveHQOgNYt
 xHKNcvOgegaFNcEY8ftKMcQ/RIVJjxXr6nPYnQyFnG0aAxYePysNx8TJaUX2dxq7
 +O1RlYHwJpRRUmScSsDFDa/CmQcpUxgloUfCmkWS611g1LZFnpVOcXEZRJg/c9lm
 hO6mH19OYlDiWeE3ZhKeYJNxmpWvPM4bxhswHcYfLG+vA93kLTYQ/xGi/0YfMKl+
 +UCTPbdiXdRyYLzixiu/NWcKwWDH2pHAH1pjimH+r2266lQYs2Jsk8436uQKhZxI
 D4l3ethujDcmMzO+ZTzLHjWbNdO2fC4R1LIF/Eg/sDe7g11dQItWYrAVddQFIkfb
 /A5VV1DbGW33tpj4QUXfjuQ65I6rLOq4NbTY3j4/lPSiDkqIpEfwjzuc3/UZeuZl
 Z8cu8Qxf7jdOfihbnUFR
 =PS0g
 -----END PGP SIGNATURE-----

Merge tag 'mac80211-for-davem-2015-05-26' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211

Johannes Berg says:

====================
We have three more fixes:
 * AP_VLAN tailroom calculation fix, the bug leads to warnings
   along with dropped packets
 * NAPI context issue, calling napi_gro_receive() from a timer
   (obviously) can lead to crashes
 * remain-on-channel combining leads to dropped requests and not
   being able to finish certain operations, so remove it
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

net/mac80211/cfg.c

@@ -2495,51 +2495,22 @@ static bool ieee80211_coalesce_started_roc(struct ieee80211_local *local,
 					   struct ieee80211_roc_work *new_roc,
 					   struct ieee80211_roc_work *cur_roc)
 {
-	unsigned long j = jiffies;
+	unsigned long now = jiffies;
-	unsigned long cur_roc_end = cur_roc->hw_start_time +
+	unsigned long remaining = cur_roc->hw_start_time +
-				    msecs_to_jiffies(cur_roc->duration);
+				  msecs_to_jiffies(cur_roc->duration) -
-	struct ieee80211_roc_work *next_roc;
+				  now;
-	int new_dur;
 
 	if (WARN_ON(!cur_roc->started || !cur_roc->hw_begun))
 		return false;
 
-	if (time_after(j + IEEE80211_ROC_MIN_LEFT, cur_roc_end))
+	/* if it doesn't fit entirely, schedule a new one */
+	if (new_roc->duration > jiffies_to_msecs(remaining))
 		return false;
 
 	ieee80211_handle_roc_started(new_roc);
 
-	new_dur = new_roc->duration - jiffies_to_msecs(cur_roc_end - j);
+	/* add to dependents so we send the expired event properly */
-
+	list_add_tail(&new_roc->list, &cur_roc->dependents);
-	/* cur_roc is long enough - add new_roc to the dependents list. */
-	if (new_dur <= 0) {
-		list_add_tail(&new_roc->list, &cur_roc->dependents);
-		return true;
-	}
-
-	new_roc->duration = new_dur;
-
-	/*
-	 * if cur_roc was already coalesced before, we might
-	 * want to extend the next roc instead of adding
-	 * a new one.
-	 */
-	next_roc = list_entry(cur_roc->list.next,
-			      struct ieee80211_roc_work, list);
-	if (&next_roc->list != &local->roc_list &&
-	    next_roc->chan == new_roc->chan &&
-	    next_roc->sdata == new_roc->sdata &&
-	    !WARN_ON(next_roc->started)) {
-		list_add_tail(&new_roc->list, &next_roc->dependents);
-		next_roc->duration = max(next_roc->duration,
-					 new_roc->duration);
-		next_roc->type = max(next_roc->type, new_roc->type);
-		return true;
-	}
-
-	/* add right after cur_roc */
-	list_add(&new_roc->list, &cur_roc->list);
-
 	return true;
 }
 
@@ -2652,17 +2623,9 @@ static int ieee80211_start_roc_work(struct ieee80211_local *local,
 			 * In the offloaded ROC case, if it hasn't begun, add
 			 * this new one to the dependent list to be handled
 			 * when the master one begins. If it has begun,
-			 * check that there's still a minimum time left and
+			 * check if it fits entirely within the existing one,
-			 * if so, start this one, transmitting the frame, but
+			 * in which case it will just be dependent as well.
-			 * add it to the list directly after this one with
+			 * Otherwise, schedule it by itself.
-			 * a reduced time so we'll ask the driver to execute
-			 * it right after finishing the previous one, in the
-			 * hope that it'll also be executed right afterwards,
-			 * effectively extending the old one.
-			 * If there's no minimum time left, just add it to the
-			 * normal list.
-			 * TODO: the ROC type is ignored here, assuming that it
-			 * is better to immediately use the current ROC.
 			 */
 			if (!tmp->hw_begun) {
 				list_add_tail(&roc->list, &tmp->dependents);

net/mac80211/ieee80211_i.h

@@ -205,6 +205,8 @@ enum ieee80211_packet_rx_flags {
  * @IEEE80211_RX_CMNTR: received on cooked monitor already
  * @IEEE80211_RX_BEACON_REPORTED: This frame was already reported
  *	to cfg80211_report_obss_beacon().
+ * @IEEE80211_RX_REORDER_TIMER: this frame is released by the
+ *	reorder buffer timeout timer, not the normal RX path
  *
  * These flags are used across handling multiple interfaces
  * for a single frame.
@@ -212,6 +214,7 @@ enum ieee80211_packet_rx_flags {
 enum ieee80211_rx_flags {
 	IEEE80211_RX_CMNTR		= BIT(0),
 	IEEE80211_RX_BEACON_REPORTED	= BIT(1),
+	IEEE80211_RX_REORDER_TIMER	= BIT(2),
 };
 
 struct ieee80211_rx_data {
@@ -325,12 +328,6 @@ struct mesh_preq_queue {
 	u8 flags;
 };
 
-#if HZ/100 == 0
-#define IEEE80211_ROC_MIN_LEFT	1
-#else
-#define IEEE80211_ROC_MIN_LEFT	(HZ/100)
-#endif
-
 struct ieee80211_roc_work {
 	struct list_head list;
 	struct list_head dependents;

net/mac80211/iface.c

@@ -522,6 +522,12 @@ int ieee80211_do_open(struct wireless_dev *wdev, bool coming_up)
 		memcpy(sdata->vif.hw_queue, master->vif.hw_queue,
 		       sizeof(sdata->vif.hw_queue));
 		sdata->vif.bss_conf.chandef = master->vif.bss_conf.chandef;
+
+		mutex_lock(&local->key_mtx);
+		sdata->crypto_tx_tailroom_needed_cnt +=
+			master->crypto_tx_tailroom_needed_cnt;
+		mutex_unlock(&local->key_mtx);
+
 		break;
 		}
 	case NL80211_IFTYPE_AP:

net/mac80211/key.c

@@ -58,6 +58,22 @@ static void assert_key_lock(struct ieee80211_local *local)
 	lockdep_assert_held(&local->key_mtx);
 }
 
+static void
+update_vlan_tailroom_need_count(struct ieee80211_sub_if_data *sdata, int delta)
+{
+	struct ieee80211_sub_if_data *vlan;
+
+	if (sdata->vif.type != NL80211_IFTYPE_AP)
+		return;
+
+	mutex_lock(&sdata->local->mtx);
+
+	list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
+		vlan->crypto_tx_tailroom_needed_cnt += delta;
+
+	mutex_unlock(&sdata->local->mtx);
+}
+
 static void increment_tailroom_need_count(struct ieee80211_sub_if_data *sdata)
 {
 	/*
@@ -79,6 +95,8 @@ static void increment_tailroom_need_count(struct ieee80211_sub_if_data *sdata)
 	 * http://mid.gmane.org/1308590980.4322.19.camel@jlt3.sipsolutions.net
 	 */
 
+	update_vlan_tailroom_need_count(sdata, 1);
+
 	if (!sdata->crypto_tx_tailroom_needed_cnt++) {
 		/*
 		 * Flush all XMIT packets currently using HW encryption or no
@@ -88,6 +106,15 @@ static void increment_tailroom_need_count(struct ieee80211_sub_if_data *sdata)
 	}
 }
 
+static void decrease_tailroom_need_count(struct ieee80211_sub_if_data *sdata,
+					 int delta)
+{
+	WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt < delta);
+
+	update_vlan_tailroom_need_count(sdata, -delta);
+	sdata->crypto_tx_tailroom_needed_cnt -= delta;
+}
+
 static int ieee80211_key_enable_hw_accel(struct ieee80211_key *key)
 {
 	struct ieee80211_sub_if_data *sdata;
@@ -144,7 +171,7 @@ static int ieee80211_key_enable_hw_accel(struct ieee80211_key *key)
 
 		if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
 		      (key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
-			sdata->crypto_tx_tailroom_needed_cnt--;
+			decrease_tailroom_need_count(sdata, 1);
 
 		WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
 			(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV));
@@ -541,7 +568,7 @@ static void __ieee80211_key_destroy(struct ieee80211_key *key,
 			schedule_delayed_work(&sdata->dec_tailroom_needed_wk,
 					      HZ/2);
 		} else {
-			sdata->crypto_tx_tailroom_needed_cnt--;
+			decrease_tailroom_need_count(sdata, 1);
 		}
 	}
 
@@ -631,6 +658,7 @@ void ieee80211_key_free(struct ieee80211_key *key, bool delay_tailroom)
 void ieee80211_enable_keys(struct ieee80211_sub_if_data *sdata)
 {
 	struct ieee80211_key *key;
+	struct ieee80211_sub_if_data *vlan;
 
 	ASSERT_RTNL();
 
@@ -639,7 +667,14 @@ void ieee80211_enable_keys(struct ieee80211_sub_if_data *sdata)
 
 	mutex_lock(&sdata->local->key_mtx);
 
-	sdata->crypto_tx_tailroom_needed_cnt = 0;
+	WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
+		     sdata->crypto_tx_tailroom_pending_dec);
+
+	if (sdata->vif.type == NL80211_IFTYPE_AP) {
+		list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
+			WARN_ON_ONCE(vlan->crypto_tx_tailroom_needed_cnt ||
+				     vlan->crypto_tx_tailroom_pending_dec);
+	}
 
 	list_for_each_entry(key, &sdata->key_list, list) {
 		increment_tailroom_need_count(sdata);
@@ -649,6 +684,22 @@ void ieee80211_enable_keys(struct ieee80211_sub_if_data *sdata)
 	mutex_unlock(&sdata->local->key_mtx);
 }
 
+void ieee80211_reset_crypto_tx_tailroom(struct ieee80211_sub_if_data *sdata)
+{
+	struct ieee80211_sub_if_data *vlan;
+
+	mutex_lock(&sdata->local->key_mtx);
+
+	sdata->crypto_tx_tailroom_needed_cnt = 0;
+
+	if (sdata->vif.type == NL80211_IFTYPE_AP) {
+		list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
+			vlan->crypto_tx_tailroom_needed_cnt = 0;
+	}
+
+	mutex_unlock(&sdata->local->key_mtx);
+}
+
 void ieee80211_iter_keys(struct ieee80211_hw *hw,
 			 struct ieee80211_vif *vif,
 			 void (*iter)(struct ieee80211_hw *hw,
@@ -688,8 +739,8 @@ static void ieee80211_free_keys_iface(struct ieee80211_sub_if_data *sdata,
 {
 	struct ieee80211_key *key, *tmp;
 
-	sdata->crypto_tx_tailroom_needed_cnt -=
+	decrease_tailroom_need_count(sdata,
-		sdata->crypto_tx_tailroom_pending_dec;
+				     sdata->crypto_tx_tailroom_pending_dec);
 	sdata->crypto_tx_tailroom_pending_dec = 0;
 
 	ieee80211_debugfs_key_remove_mgmt_default(sdata);
@@ -709,6 +760,7 @@ void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata,
 {
 	struct ieee80211_local *local = sdata->local;
 	struct ieee80211_sub_if_data *vlan;
+	struct ieee80211_sub_if_data *master;
 	struct ieee80211_key *key, *tmp;
 	LIST_HEAD(keys);
 
@@ -728,8 +780,20 @@ void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata,
 	list_for_each_entry_safe(key, tmp, &keys, list)
 		__ieee80211_key_destroy(key, false);
 
-	WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
+	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
-		     sdata->crypto_tx_tailroom_pending_dec);
+		if (sdata->bss) {
+			master = container_of(sdata->bss,
+					      struct ieee80211_sub_if_data,
+					      u.ap);
+
+			WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt !=
+				     master->crypto_tx_tailroom_needed_cnt);
+		}
+	} else {
+		WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt ||
+			     sdata->crypto_tx_tailroom_pending_dec);
+	}
+
 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
 		list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
 			WARN_ON_ONCE(vlan->crypto_tx_tailroom_needed_cnt ||
@@ -793,8 +857,8 @@ void ieee80211_delayed_tailroom_dec(struct work_struct *wk)
 	 */
 
 	mutex_lock(&sdata->local->key_mtx);
-	sdata->crypto_tx_tailroom_needed_cnt -=
+	decrease_tailroom_need_count(sdata,
-		sdata->crypto_tx_tailroom_pending_dec;
+				     sdata->crypto_tx_tailroom_pending_dec);
 	sdata->crypto_tx_tailroom_pending_dec = 0;
 	mutex_unlock(&sdata->local->key_mtx);
 }

net/mac80211/key.h

@@ -161,6 +161,7 @@ void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata,
 void ieee80211_free_sta_keys(struct ieee80211_local *local,
 			     struct sta_info *sta);
 void ieee80211_enable_keys(struct ieee80211_sub_if_data *sdata);
+void ieee80211_reset_crypto_tx_tailroom(struct ieee80211_sub_if_data *sdata);
 
 #define key_mtx_dereference(local, ref) \
 	rcu_dereference_protected(ref, lockdep_is_held(&((local)->key_mtx)))

net/mac80211/rx.c

@@ -2121,7 +2121,8 @@ ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
 		/* deliver to local stack */
 		skb->protocol = eth_type_trans(skb, dev);
 		memset(skb->cb, 0, sizeof(skb->cb));
-		if (rx->local->napi)
+		if (!(rx->flags & IEEE80211_RX_REORDER_TIMER) &&
+		    rx->local->napi)
 			napi_gro_receive(rx->local->napi, skb);
 		else
 			netif_receive_skb(skb);
@@ -3231,7 +3232,7 @@ void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
 		/* This is OK -- must be QoS data frame */
 		.security_idx = tid,
 		.seqno_idx = tid,
-		.flags = 0,
+		.flags = IEEE80211_RX_REORDER_TIMER,
 	};
 	struct tid_ampdu_rx *tid_agg_rx;
 

net/mac80211/util.c

@@ -2022,6 +2022,9 @@ int ieee80211_reconfig(struct ieee80211_local *local)
 	mutex_unlock(&local->sta_mtx);
 
 	/* add back keys */
+	list_for_each_entry(sdata, &local->interfaces, list)
+		ieee80211_reset_crypto_tx_tailroom(sdata);
+
 	list_for_each_entry(sdata, &local->interfaces, list)
 		if (ieee80211_sdata_running(sdata))
 			ieee80211_enable_keys(sdata);