[PATCH 1/2] mac80211: Dont allow to wake up netif tx queues while on off channel

[Vasanthakumar Thiagarajan <vasanth@atheros.com>]

Drivers are not supposed to call ieee80211_wake_queue() while operating
on off channel during sw scanning, but there is no clear way for
the driver to know that it is operating on off channel during scanning.
There are cases (unavailablity/availability of tx buffers in ath9k, for
example) where driver needs to stop/restart tx queues during background
scanning state, this might result in waking up the corresponding netif
tx queue when the device is on off channel which is not desired. This
patches fixes this by checking SCAN_OFF_CHANNEL bit in scanning before
restarting the tx queue.

Signed-off-by: Vasanthakumar Thiagarajan <vasanth@atheros.com>
---
 net/mac80211/util.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index a54cf14..1938a67 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -277,7 +277,8 @@ static void __ieee80211_wake_queue(struct ieee80211_hw *hw, int queue,
 
 	__clear_bit(reason, &local->queue_stop_reasons[queue]);
 
-	if (local->queue_stop_reasons[queue] != 0)
+	if ((local->queue_stop_reasons[queue] != 0) ||
+	    test_bit(SCAN_OFF_CHANNEL, &local->scanning))
 		/* someone still has this queue stopped */
 		return;
 
-- 
1.7.0.4