mac80211: detect driver tx bugs

When a driver rejects a frame in it's ->tx() callback, it must also
stop queues, otherwise mac80211 can go into a loop here. Detect this
situation and abort the loop after five retries, warning about the
driver bug.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Johannes Berg 2008-06-18 15:39:48 -07:00 committed by David S. Miller
parent 6d1a3fb567
commit ef3a62d272

View File

@ -1132,7 +1132,7 @@ static int ieee80211_tx(struct net_device *dev, struct sk_buff *skb,
ieee80211_tx_handler *handler;
struct ieee80211_tx_data tx;
ieee80211_tx_result res = TX_DROP, res_prepare;
int ret, i;
int ret, i, retries = 0;
WARN_ON(__ieee80211_queue_pending(local, control->queue));
@ -1216,6 +1216,13 @@ static int ieee80211_tx(struct net_device *dev, struct sk_buff *skb,
if (!__ieee80211_queue_stopped(local, control->queue)) {
clear_bit(IEEE80211_LINK_STATE_PENDING,
&local->state[control->queue]);
retries++;
/*
* Driver bug, it's rejecting packets but
* not stopping queues.
*/
if (WARN_ON_ONCE(retries > 5))
goto drop;
goto retry;
}
memcpy(&store->control, control,