mac80211: Fix the wrong WARN_ON message appearing on enabling power save.

This issue happens only when we are associated with a 11n AP and power save
is enabled. In the function 'ieee80211_master_start_xmit', ps_disable_work
is queued where wake_queues is called. But before this work is executed,
we check if the queues are stopped in _ieee80211_tx and return TX_AGAIN to
ieee8011_tx which leads to the warning message.
This patch fixes this erroneous case.

Signed-off-by: Vivek Natarajan <vnatarajan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index f1c726d..bf73f6d 100644 (file)
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -35,6 +35,7 @@
 #define IEEE80211_TX_OK                0
 #define IEEE80211_TX_AGAIN     1
 #define IEEE80211_TX_FRAG_AGAIN        2
+#define IEEE80211_TX_PENDING   3
 
 /* misc utils */
 
@@ -1085,7 +1086,7 @@ static int __ieee80211_tx(struct ieee80211_local *local, struct sk_buff *skb,
 
        if (skb) {
                if (netif_subqueue_stopped(local->mdev, skb))
-                       return IEEE80211_TX_AGAIN;
+                       return IEEE80211_TX_PENDING;
 
                ret = local->ops->tx(local_to_hw(local), skb);
                if (ret)
@@ -1211,8 +1212,9 @@ retry:
                 * queues, there's no reason for a driver to reject
                 * a frame there, warn and drop it.
                 */
-               if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU))
-                       goto drop;
+               if (ret != IEEE80211_TX_PENDING)
+                       if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU))
+                               goto drop;
 
                store = &local->pending_packet[queue];