diff options
| author | Johannes Berg <johannes@sipsolutions.net> | 2008-07-02 20:36:31 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2008-07-24 09:14:02 -0700 |
| commit | da1be4d48515fde4eab98c776726747f7694f59f (patch) | |
| tree | a803ad7b653ae905f1aaf8e143720a95adbb28f6 | |
| parent | 204b304df21a73cce2210eae236de6caaf3bc09b (diff) | |
| download | lwn-da1be4d48515fde4eab98c776726747f7694f59f.tar.gz lwn-da1be4d48515fde4eab98c776726747f7694f59f.zip | |
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.
This patch was added to mainline as
commit ef3a62d272f033989e83eb1f26505f93f93e3e69.
Thanks to Larry Finger <Larry.Finger@lwfinger.net> for doing the -stable
port.
Cc: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/mac80211/tx.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index 67b509edd431..9bdaed803b8f 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -1090,7 +1090,7 @@ static int ieee80211_tx(struct net_device *dev, struct sk_buff *skb, ieee80211_tx_handler *handler; struct ieee80211_txrx_data tx; ieee80211_txrx_result res = TXRX_DROP, res_prepare; - int ret, i; + int ret, i, retries = 0; WARN_ON(__ieee80211_queue_pending(local, control->queue)); @@ -1181,6 +1181,13 @@ retry: 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, |