We observe unexpected connection drops with some APs due to non-acked mac80211 generated null data frames (keep-alive). After debugging and capture, we noticed that null frames are submitted at standard data bitrate and that the given APs are in trouble with that.
After setting the null frame bitrate to control bitrate, all null frames are acked as expected and connection is maintained.
Not sure if it's a requirement of the specification, but it seems the right thing to do anyway, null frames are mostly used for control purpose (power-saving, keep-alive...), and submitting them with a slower/simpler bitrate/modulation is more robust.
Cc: stable@vger.kernel.org Fixes: 512b191d9652 ("wcn36xx: Fix TX data path") Signed-off-by: Loic Poulain loic.poulain@linaro.org --- drivers/net/wireless/ath/wcn36xx/txrx.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/net/wireless/ath/wcn36xx/txrx.c b/drivers/net/wireless/ath/wcn36xx/txrx.c index ef1b133..ce4f631 100644 --- a/drivers/net/wireless/ath/wcn36xx/txrx.c +++ b/drivers/net/wireless/ath/wcn36xx/txrx.c @@ -535,6 +535,7 @@ static void wcn36xx_set_tx_data(struct wcn36xx_tx_bd *bd, if (ieee80211_is_any_nullfunc(hdr->frame_control)) { /* Don't use a regular queue for null packet (no ampdu) */ bd->queue_id = WCN36XX_TX_U_WQ_ID; + bd->bd_rate = WCN36XX_BD_RATE_CTRL; }
if (bcast) {