You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
61 lines
1.9 KiB
Diff
61 lines
1.9 KiB
Diff
From: Sujith Manoharan <c_manoha@qca.qualcomm.com>
|
|
Date: Fri, 17 Oct 2014 07:40:30 +0530
|
|
Subject: [PATCH] ath9k: Do not start BA when scanning
|
|
|
|
mac80211 currently has a race which can be hit
|
|
with this sequence:
|
|
|
|
* Start a scan operation.
|
|
* TX BA is initiated by ieee80211_start_tx_ba_session().
|
|
* Driver sets up internal state and calls
|
|
ieee80211_start_tx_ba_cb_irqsafe().
|
|
* mac80211 adds a packet to sdata->skb_queue with
|
|
type IEEE80211_SDATA_QUEUE_AGG_START.
|
|
* ieee80211_iface_work() doesn't process the
|
|
packet because scan is in progress.
|
|
* ADDBA response timer expires and the sta/tid is
|
|
torn down.
|
|
* Driver receives BA stop notification and calls
|
|
ieee80211_stop_tx_ba_cb_irqsafe().
|
|
* This is also added to the queue by mac80211.
|
|
* Now, scan finishes.
|
|
|
|
At this point, the queued up packets might be processed
|
|
if some other operation schedules the sdata work. Since
|
|
the tids have been cleaned up already, warnings are hit.
|
|
|
|
If this doesn't happen, the packets are left in the queue
|
|
until the interface is torn down.
|
|
|
|
Since initiating a BA session when scan is in progress
|
|
leads to flaky connections, especially in MCC mode, we
|
|
can drop the TX BA request. This improves connectivity
|
|
with legacy clients in MCC mode.
|
|
|
|
Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
|
|
---
|
|
|
|
--- a/drivers/net/wireless/ath/ath9k/main.c
|
|
+++ b/drivers/net/wireless/ath/ath9k/main.c
|
|
@@ -1885,6 +1885,7 @@ static int ath9k_ampdu_action(struct iee
|
|
u16 tid, u16 *ssn, u8 buf_size)
|
|
{
|
|
struct ath_softc *sc = hw->priv;
|
|
+ struct ath_common *common = ath9k_hw_common(sc->sc_ah);
|
|
bool flush = false;
|
|
int ret = 0;
|
|
|
|
@@ -1896,6 +1897,12 @@ static int ath9k_ampdu_action(struct iee
|
|
case IEEE80211_AMPDU_RX_STOP:
|
|
break;
|
|
case IEEE80211_AMPDU_TX_START:
|
|
+ if (ath9k_is_chanctx_enabled()) {
|
|
+ if (test_bit(ATH_OP_SCANNING, &common->op_flags)) {
|
|
+ ret = -EBUSY;
|
|
+ break;
|
|
+ }
|
|
+ }
|
|
ath9k_ps_wakeup(sc);
|
|
ret = ath_tx_aggr_start(sc, sta, tid, ssn);
|
|
if (!ret)
|