3.14-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Felix Fietkau <redacted>

commit c01fac1c77a00227f706a1654317023e3f4ac7f0 upstream.

If an aggregation session fails, frames still end up in the driver queue
with IEEE80211_TX_CTL_AMPDU set.
This causes tx for the affected station/tid to stall, since
ath_tx_get_tid_subframe returning packets to send.

Fix this by clearing IEEE80211_TX_CTL_AMPDU as long as no aggregation
session is running.

Reported-by: Antonio Quartulli <redacted>
Signed-off-by: Felix Fietkau <redacted>
Signed-off-by: John W. Linville <redacted>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/net/wireless/ath/ath9k/xmit.c |    9 +++++++++
 1 file changed, 9 insertions(+)

--- a/drivers/net/wireless/ath/ath9k/xmit.c
+++ b/drivers/net/wireless/ath/ath9k/xmit.c

@@ -890,6 +890,15 @@ ath_tx_get_tid_subframe(struct ath_softc
 
 		tx_info = IEEE80211_SKB_CB(skb);
 		tx_info->flags &= ~IEEE80211_TX_CTL_CLEAR_PS_FILT;
+
+		/*
+		 * No aggregation session is running, but there may be frames
+		 * from a previous session or a failed attempt in the queue.
+		 * Send them out as normal data frames
+		 */
+		if (!tid->active)
+			tx_info->flags &= ~IEEE80211_TX_CTL_AMPDU;
+
 		if (!(tx_info->flags & IEEE80211_TX_CTL_AMPDU)) {
 			bf->bf_state.bf_type = 0;
 			return bf;