Commit a4c2b8be authored Mar 04, 2026 by Eric Dumazet Committed by Jakub Kicinski Mar 04, 2026

net_sched: sch_fq: clear q->band_pkt_count[] in fq_reset()



When/if a NIC resets, queues are deactivated by dev_deactivate_many(),
then reactivated when the reset operation completes.

fq_reset() removes all the skbs from various queues.

If we do not clear q->band_pkt_count[], these counters keep growing
and can eventually reach sch->limit, preventing new packets to be queued.

Many thanks to Praveen for discovering the root cause.

Fixes: 29f834aa ("net_sched: sch_fq: add 3 bands and WRR scheduling")
Diagnosed-by: Praveen Kaligineedi <pkaligineedi@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Neal Cardwell <ncardwell@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260304015640.961780-1-edumazet@google.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>

parent f7d92f11

net/sched/sch_fq.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -827,6 +827,7 @@ static void fq_reset(struct Qdisc *sch)
		for (idx = 0; idx < FQ_BANDS; idx++) {
		q->band_flows[idx].new_flows.first = NULL;
		q->band_flows[idx].old_flows.first = NULL;
		q->band_pkt_count[idx] = 0;
		}
		q->delayed = RB_ROOT;
		q->flows = 0;