mac80211: add comment for rx_path_lock

Add a comment explaining how the RX path lock is used.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index bdabf34..6accd61 100644 (file)
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -3123,6 +3123,12 @@ static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx,
                        goto rxh_next;  \
        } while (0);
 
+       /* Lock here to avoid hitting all of the data used in the RX
+        * path (e.g. key data, station data, ...) concurrently when
+        * a frame is released from the reorder buffer due to timeout
+        * from the timer, potentially concurrently with RX from the
+        * driver.
+        */
        spin_lock_bh(&rx->local->rx_path_lock);
 
        while ((skb = __skb_dequeue(frames))) {