[PATCH net 2/2] net: ethernet: mtk_eth_soc: fix L2 offloading with DSA untag offload enabled

[Felix Fietkau <nbd@nbd.name>]

Check for skb metadata in order to detect the case where the DSA header is not
present.

Fixes: 2d7605a72906 ("net: ethernet: mtk_eth_soc: enable hardware DSA untagging")
Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
 drivers/net/ethernet/mediatek/mtk_eth_soc.c | 6 +++---
 drivers/net/ethernet/mediatek/mtk_ppe.c     | 5 ++++-
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
index 3cb43623d3db..a94aa08515af 100644
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
@@ -2059,9 +2059,6 @@ static int mtk_poll_rx(struct napi_struct *napi, int budget,
 			skb_checksum_none_assert(skb);
 		skb->protocol = eth_type_trans(skb, netdev);
 
-		if (reason == MTK_PPE_CPU_REASON_HIT_UNBIND_RATE_REACHED)
-			mtk_ppe_check_skb(eth->ppe[0], skb, hash);
-
 		if (netdev->features & NETIF_F_HW_VLAN_CTAG_RX) {
 			if (MTK_HAS_CAPS(eth->soc->caps, MTK_NETSYS_V2)) {
 				if (trxd.rxd3 & RX_DMA_VTAG_V2) {
@@ -2089,6 +2086,9 @@ static int mtk_poll_rx(struct napi_struct *napi, int budget,
 			__vlan_hwaccel_put_tag(skb, htons(vlan_proto), vlan_tci);
 		}
 
+		if (reason == MTK_PPE_CPU_REASON_HIT_UNBIND_RATE_REACHED)
+			mtk_ppe_check_skb(eth->ppe[0], skb, hash);
+
 		skb_record_rx_queue(skb, 0);
 		napi_gro_receive(napi, skb);
 
diff --git a/drivers/net/ethernet/mediatek/mtk_ppe.c b/drivers/net/ethernet/mediatek/mtk_ppe.c
index 6883eb34cd8b..a038b99ecbda 100644
--- a/drivers/net/ethernet/mediatek/mtk_ppe.c
+++ b/drivers/net/ethernet/mediatek/mtk_ppe.c
@@ -8,6 +8,7 @@
 #include <linux/platform_device.h>
 #include <linux/if_ether.h>
 #include <linux/if_vlan.h>
+#include <net/dst_metadata.h>
 #include <net/dsa.h>
 #include "mtk_eth_soc.h"
 #include "mtk_ppe.h"
@@ -699,7 +700,9 @@ void __mtk_ppe_check_skb(struct mtk_ppe *ppe, struct sk_buff *skb, u16 hash)
 		    skb->dev->dsa_ptr->tag_ops->proto != DSA_TAG_PROTO_MTK)
 			goto out;
 
-		tag += 4;
+		if (!skb_metadata_dst(skb))
+			tag += 4;
+
 		if (get_unaligned_be16(tag) != ETH_P_8021Q)
 			break;
 
-- 
2.39.0