From 574be53ab82c3525236c8a3dd70f3dcaebd9e9aa Mon Sep 17 00:00:00 2001 From: Bob Copeland Date: Wed, 5 Sep 2018 06:22:59 -0400 Subject: [PATCH] mac80211: fix pending queue hang due to TX_DROP MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit [ Upstream commit 6eae4a6c2be387fec41b0d2782c4fffb57159498 ] In our environment running lots of mesh nodes, we are seeing the pending queue hang periodically, with the debugfs queues file showing lines such as: 00: 0x00000000/348 i.e. there are a large number of frames but no stop reason set. One way this could happen is if queue processing from the pending tasklet exited early without processing all frames, and without having some future event (incoming frame, stop reason flag, ...) to reschedule it. Exactly this can occur today if ieee80211_tx() returns false due to packet drops or power-save buffering in the tx handlers. In the past, this function would return true in such cases, and the change to false doesn't seem to be intentional. Fix this case by reverting to the previous behavior. Fixes: bb42f2d13ffc ("mac80211: Move reorder-sensitive TX handlers to after TXQ dequeue") Signed-off-by: Bob Copeland Acked-by: Toke Høiland-Jørgensen Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin --- net/mac80211/tx.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index d8fddd88bf46..a17a56032a21 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -1837,7 +1837,7 @@ static bool ieee80211_tx(struct ieee80211_sub_if_data *sdata, sdata->vif.hw_queue[skb_get_queue_mapping(skb)]; if (invoke_tx_handlers_early(&tx)) - return false; + return true; if (ieee80211_queue_skb(local, sdata, tx.sta, tx.skb)) return true;