4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx> [ Upstream commit 325d5dc3f7e7c2840b65e4a2988c082c2c0025c5 ] When sfq_enqueue() drops head packet or packet from another queue it have to update backlog at upper qdiscs too. Fixes: 2ccccf5fb43f ("net_sched: update hierarchical backlog too") Signed-off-by: Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx> Acked-by: Eric Dumazet <edumazet@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/sched/sch_sfq.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) --- a/net/sched/sch_sfq.c +++ b/net/sched/sch_sfq.c @@ -434,6 +434,7 @@ congestion_drop: qdisc_drop(head, sch, to_free); slot_queue_add(slot, skb); + qdisc_tree_reduce_backlog(sch, 0, delta); return NET_XMIT_CN; } @@ -465,8 +466,10 @@ enqueue: /* Return Congestion Notification only if we dropped a packet * from this flow. */ - if (qlen != slot->qlen) + if (qlen != slot->qlen) { + qdisc_tree_reduce_backlog(sch, 0, dropped - qdisc_pkt_len(skb)); return NET_XMIT_CN; + } /* As we dropped a packet, better let upper stack know this */ qdisc_tree_reduce_backlog(sch, 1, dropped);