hsr: ratelimit only when errors are printed

Recently, when automatically merging -net and net-next in MPTCP devel
tree, our CI reported [1] a conflict in hsr, the same as the one
reported by Stephen in netdev [2].

When looking at the conflict, I noticed it is in fact the v1 [3] that
has been applied in -net and the v2 [4] in net-next. Maybe the v1 was
applied by accident.

As mentioned by Jakub Kicinski [5], the new condition makes more sense
before the net_ratelimit(), not to update net_ratelimit's state which is
unnecessary if we're not going to print either way.

Here, this modification applies the v2 but in -net.

Link: https://github.com/multipath-tcp/mptcp_net-next/actions/runs/4423171069 [1]
Link: https://lore.kernel.org/netdev/[email protected]/ [2]
Link: https://lore.kernel.org/netdev/[email protected]/ [3]
Link: https://lore.kernel.org/netdev/[email protected]/ [4]
Link: https://lore.kernel.org/netdev/[email protected]/ [5]
Fixes: 28e8cab ("net: hsr: Don't log netdev_err message on unknown prp dst node")
Signed-off-by: Matthieu Baerts <[email protected]>
Reviewed-by: Steen Hegelund <[email protected]>
Link: https://lore.kernel.org/r/20230315-net-20230315-hsr_framereg-ratelimit-v1-1-61d2ef176d11@tessares.net
Signed-off-by: Jakub Kicinski <[email protected]>

Author: matttbe

net/hsr/hsr_framereg.c

@@ -415,7 +415,7 @@ void hsr_addr_subst_dest(struct hsr_node *node_src, struct sk_buff *skb,
 	node_dst = find_node_by_addr_A(&port->hsr->node_db,
 				       eth_hdr(skb)->h_dest);
 	if (!node_dst) {
-		if (net_ratelimit() && port->hsr->prot_version != PRP_V1)
+		if (port->hsr->prot_version != PRP_V1 && net_ratelimit())
 			netdev_err(skb->dev, "%s: Unknown node\n", __func__);
 		return;
 	}