On Sun, Oct 04, 2026 at 07:16:35PM +0200, Julius Bairaktaris wrote: > Packets forwarded by the flowtable skip the ruleset, so a priority set > by "meta priority set" before "flow add" only applies to the first > packets of a connection, and drivers never see it. > > Store skb->priority of the packet that creates the flow, apply it in > the software fast path and emit it as FLOW_ACTION_PRIORITY, the action > act_skbedit uses. Flows without a priority are unchanged. On IPv4, > ip_forward() derives a priority from the TOS by default, so a flow can > carry one without a rule. The priority applies to both directions. > > airoha uses it as the QoS queue of flows that leave through a GDM port, > as its software path does, mtk ignores it like FLOW_ACTION_CSUM, and > mlx5 ignores it on flowtable flows (previous patch). airoha and mtk > parse tc flower rules in the same function, so they now also accept > skbedit priority there.
I think we already mentioned this only works for hardware, this is a no-go. > Assisted-by: Claude:claude-opus-5 > Signed-off-by: Julius Bairaktaris <[email protected]> > --- > Documentation/networking/nf_flowtable.rst | 4 +++- > drivers/net/ethernet/airoha/airoha_ppe.c | 3 +++ > drivers/net/ethernet/mediatek/mtk_ppe_offload.c | 1 + > include/net/netfilter/nf_flow_table.h | 1 + > net/netfilter/nf_flow_table_ip.c | 6 ++++++ > net/netfilter/nf_flow_table_offload.c | 11 +++++++++++ > net/netfilter/nft_flow_offload.c | 2 ++ > 7 files changed, 27 insertions(+), 1 deletion(-) > > diff --git a/Documentation/networking/nf_flowtable.rst > b/Documentation/networking/nf_flowtable.rst > index d757c21c10f2..5844ab19aec6 100644 > --- a/Documentation/networking/nf_flowtable.rst > +++ b/Documentation/networking/nf_flowtable.rst > @@ -71,7 +71,9 @@ forwarding path including the Netfilter hooks and the > flowtable fastpath bypass. > > The flowtable entry also stores the NAT configuration, so all packets are > mangled according to the NAT policy that is specified from the classic IP > -forwarding path. The TTL is decremented before calling neigh_xmit(). > Fragmented > +forwarding path. The TTL is decremented before calling neigh_xmit(). The flow > +also stores the priority of the packet that created it, so a priority set > before > +``flow add`` applies to the packets that the flowtable forwards. Fragmented > traffic is passed up to follow the classic IP forwarding path given that the > transport header is missing, in this case, flowtable lookups are not > possible. > TCP RST and FIN packets are also passed up to the classic IP forwarding path > to > diff --git a/drivers/net/ethernet/airoha/airoha_ppe.c > b/drivers/net/ethernet/airoha/airoha_ppe.c > index 92611802801e..e790305ea955 100644 > --- a/drivers/net/ethernet/airoha/airoha_ppe.c > +++ b/drivers/net/ethernet/airoha/airoha_ppe.c > @@ -1161,6 +1161,9 @@ static int airoha_ppe_flow_offload_replace(struct > airoha_eth *eth, > case FLOW_ACTION_REDIRECT: > odev = act->dev; > break; > + case FLOW_ACTION_PRIORITY: > + priority = act->priority; > + break; > case FLOW_ACTION_CSUM: > break; > case FLOW_ACTION_VLAN_PUSH: > diff --git a/drivers/net/ethernet/mediatek/mtk_ppe_offload.c > b/drivers/net/ethernet/mediatek/mtk_ppe_offload.c > index 99b28aaa7cc4..4ee99e8e4a34 100644 > --- a/drivers/net/ethernet/mediatek/mtk_ppe_offload.c > +++ b/drivers/net/ethernet/mediatek/mtk_ppe_offload.c > @@ -378,6 +378,7 @@ mtk_flow_offload_replace(struct mtk_eth *eth, struct > flow_cls_offload *f, > case FLOW_ACTION_REDIRECT: > odev = act->dev; > break; > + case FLOW_ACTION_PRIORITY: > case FLOW_ACTION_CSUM: > break; > case FLOW_ACTION_VLAN_PUSH: > diff --git a/include/net/netfilter/nf_flow_table.h > b/include/net/netfilter/nf_flow_table.h > index f2e2771f188f..23218c8cbc3d 100644 > --- a/include/net/netfilter/nf_flow_table.h > +++ b/include/net/netfilter/nf_flow_table.h > @@ -202,6 +202,7 @@ struct flow_offload { > unsigned long flags; > u16 type; > u32 timeout; > + u32 priority; > struct rcu_head rcu_head; > }; > > diff --git a/net/netfilter/nf_flow_table_ip.c > b/net/netfilter/nf_flow_table_ip.c > index c8c29a9a1684..c85e2d608c32 100644 > --- a/net/netfilter/nf_flow_table_ip.c > +++ b/net/netfilter/nf_flow_table_ip.c > @@ -509,6 +509,9 @@ static int nf_flow_offload_forward(struct > nf_flowtable_ctx *ctx, > ip_decrease_ttl(iph); > skb_clear_tstamp(skb); > > + if (flow->priority) > + skb->priority = flow->priority; > + > if (flow_table->flags & NF_FLOWTABLE_COUNTER) > nf_ct_acct_update(flow->ct, tuplehash->tuple.dir, skb->len); > > @@ -1104,6 +1107,9 @@ static int nf_flow_offload_ipv6_forward(struct > nf_flowtable_ctx *ctx, > ip6h->hop_limit--; > skb_clear_tstamp(skb); > > + if (flow->priority) > + skb->priority = flow->priority; > + > if (flow_table->flags & NF_FLOWTABLE_COUNTER) > nf_ct_acct_update(flow->ct, tuplehash->tuple.dir, skb->len); > > diff --git a/net/netfilter/nf_flow_table_offload.c > b/net/netfilter/nf_flow_table_offload.c > index 801a3dd9ceea..caaadffc2563 100644 > --- a/net/netfilter/nf_flow_table_offload.c > +++ b/net/netfilter/nf_flow_table_offload.c > @@ -696,6 +696,17 @@ nf_flow_rule_route_common(struct net *net, const struct > flow_offload *flow, > flow_offload_eth_dst(net, flow, dir, flow_rule) < 0) > return -1; > > + if (flow->priority) { > + struct flow_action_entry *entry; > + > + entry = flow_action_entry_next(flow_rule); > + if (!entry) > + return -1; > + > + entry->id = FLOW_ACTION_PRIORITY; > + entry->priority = flow->priority; > + } > + > tuple = &flow->tuplehash[dir].tuple; > > for (i = 0; i < tuple->encap_num; i++) { > diff --git a/net/netfilter/nft_flow_offload.c > b/net/netfilter/nft_flow_offload.c > index 32b4281038dd..c8eaf7bc356d 100644 > --- a/net/netfilter/nft_flow_offload.c > +++ b/net/netfilter/nft_flow_offload.c > @@ -117,6 +117,8 @@ static void nft_flow_offload_eval(const struct nft_expr > *expr, > if (tcph) > flow_offload_ct_tcp(ct); > > + flow->priority = pkt->skb->priority; > + > __set_bit(NF_FLOW_HW_BIDIRECTIONAL, &flow->flags); > ret = flow_offload_add(flowtable, flow); > if (ret < 0) > -- > 2.53.0 > >
