From eae0dbf68cb973d7b629d65c3a2645ccaef7410a Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Tue, 15 Feb 2022 15:16:31 +0100 Subject: [PATCH] mac80211: fix traffic stalls on forwarded mesh packets due to wrong AC selection Signed-off-by: Felix Fietkau --- ...warded-mesh-frames-AC-queue-selectio.patch | 50 +++++++++++++++++++ 1 file changed, 50 insertions(+) create mode 100644 package/kernel/mac80211/patches/subsys/322-mac80211-fix-forwarded-mesh-frames-AC-queue-selectio.patch diff --git a/package/kernel/mac80211/patches/subsys/322-mac80211-fix-forwarded-mesh-frames-AC-queue-selectio.patch b/package/kernel/mac80211/patches/subsys/322-mac80211-fix-forwarded-mesh-frames-AC-queue-selectio.patch new file mode 100644 index 0000000000..50693f7232 --- /dev/null +++ b/package/kernel/mac80211/patches/subsys/322-mac80211-fix-forwarded-mesh-frames-AC-queue-selectio.patch @@ -0,0 +1,50 @@ +From: Nicolas Escande +Date: Mon, 14 Feb 2022 18:32:14 +0100 +Subject: [PATCH] mac80211: fix forwarded mesh frames AC & queue selection + +There are two problems with the current code that have been highlighted +with the AQL feature that is now enbaled by default. + +First problem is in ieee80211_rx_h_mesh_fwding(), +ieee80211_select_queue_80211() is used on received packets to choose +the sending AC queue of the forwarding packet although this function +should only be called on TX packet (it uses ieee80211_tx_info). +This ends with forwarded mesh packets been sent on unrelated random AC +queue. To fix that, AC queue can directly be infered from skb->priority +which has been extracted from QOS info (see ieee80211_parse_qos()). + +Second problem is the value of queue_mapping set on forwarded mesh +frames via skb_set_queue_mapping() is not the AC of the packet but a +hardware queue index. This may or may not work depending on AC to HW +queue mapping which is driver specific. + +Both of these issues lead to improper AC selection while forwarding +mesh packets but more importantly due to improper airtime accounting +(which is done on a per STA, per AC basis) caused traffic stall with +the introduction of AQL. + +Fixes: cf44012810cc ("mac80211: fix unnecessary frame drops in mesh fwding") +Fixes: d3c1597b8d1b ("mac80211: fix forwarded mesh frame queue mapping") +Co-developed-by: Remi Pommarel +Signed-off-by: Remi Pommarel +Signed-off-by: Nicolas Escande +--- + +--- a/net/mac80211/rx.c ++++ b/net/mac80211/rx.c +@@ -2921,13 +2921,13 @@ ieee80211_rx_h_mesh_fwding(struct ieee80 + ether_addr_equal(sdata->vif.addr, hdr->addr3)) + return RX_CONTINUE; + +- ac = ieee80211_select_queue_80211(sdata, skb, hdr); ++ ac = ieee802_1d_to_ac[skb->priority]; + q = sdata->vif.hw_queue[ac]; + if (ieee80211_queue_stopped(&local->hw, q)) { + IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_congestion); + return RX_DROP_MONITOR; + } +- skb_set_queue_mapping(skb, q); ++ skb_set_queue_mapping(skb, ac); + + if (!--mesh_hdr->ttl) { + if (!is_multicast_ether_addr(hdr->addr1)) -- 2.30.2