From: Felix Fietkau <nbd@nbd.name>
Date: Thu, 31 Aug 2023 21:48:38 +0200
Subject: [PATCH] netfilter: nf_tables: ignore -EOPNOTSUPP on flowtable device
 offload setup

On many embedded devices, it is common to configure flowtable offloading for
a mix of different devices, some of which have hardware offload support and
some of which don't.
The current code limits the ability of user space to properly set up such a
configuration by only allowing adding devices with hardware offload support to
a offload-enabled flowtable.
Given that offload-enabled flowtables also imply fallback to pure software
offloading, this limitation makes little sense.
Fix it by not bailing out when the offload setup returns -EOPNOTSUPP

Signed-off-by: Felix Fietkau <nbd@nbd.name>
---

--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -7752,7 +7752,7 @@ static int nft_register_flowtable_net_ho
 		err = flowtable->data.type->setup(&flowtable->data,
 						  hook->ops.dev,
 						  FLOW_BLOCK_BIND);
-		if (err < 0)
+		if (err < 0 && err != -EOPNOTSUPP)
 			goto err_unregister_net_hooks;
 
 		err = nf_register_net_hook(net, &hook->ops);
