ath9k: fix aggregation session lockup

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 <antonio@open-mesh.com>
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/net/wireless/ath/ath9k/xmit.c b/drivers/net/wireless/ath/ath9k/xmit.c
index 0526ddf..0fe7674 100644 (file)
--- 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 *sc, struct ath_txq *txq,
 
                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;