From ab277d2084ba59956b177a7d417791a27361e283 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Tue, 11 Apr 2023 21:01:52 +0300 Subject: net/sched: mqprio: add an extack message to mqprio_parse_opt() Ferenc reports that a combination of poor iproute2 defaults and obscure cases where the kernel returns -EINVAL make it difficult to understand what is wrong with this command: $ ip link add veth0 numtxqueues 8 numrxqueues 8 type veth peer name veth1 $ tc qdisc add dev veth0 root mqprio num_tc 8 map 0 1 2 3 4 5 6 7 \ queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 RTNETLINK answers: Invalid argument Hopefully with this patch, the cause is clearer: Error: Device does not support hardware offload. The kernel was (and still is) rejecting this because iproute2 defaults to "hw 1" if this command line option is not specified. Link: https://lore.kernel.org/netdev/ede5e9a2f27bf83bfb86d3e8c4ca7b34093b99e2.camel@inf.elte.hu/ Signed-off-by: Vladimir Oltean Reviewed-by: Ferenc Fejes Reviewed-by: Simon Horman Acked-by: Jamal Hadi Salim Signed-off-by: Jakub Kicinski --- net/sched/sch_mqprio.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/net/sched/sch_mqprio.c b/net/sched/sch_mqprio.c index 8e8151ca8307..aae4d64dbf3f 100644 --- a/net/sched/sch_mqprio.c +++ b/net/sched/sch_mqprio.c @@ -133,8 +133,11 @@ static int mqprio_parse_opt(struct net_device *dev, struct tc_mqprio_qopt *qopt, /* If ndo_setup_tc is not present then hardware doesn't support offload * and we should return an error. */ - if (qopt->hw && !dev->netdev_ops->ndo_setup_tc) + if (qopt->hw && !dev->netdev_ops->ndo_setup_tc) { + NL_SET_ERR_MSG(extack, + "Device does not support hardware offload"); return -EINVAL; + } return 0; } -- cgit