kernel: mtk_eth_soc: fix tx vlan tag for llc packets

When sending llc packets with vlan tx offload, the hardware fails to
actually add the tag. Deal with this by fixing it up in software.

Fixes: https://github.com/openwrt/openwrt/issues/19916
Reported-by: Thibaut VARENE <[email protected]>
Signed-off-by: Felix Fietkau <[email protected]>

diff --git a/target/linux/generic/hack-6.12/730-net-ethernet-mtk_eth_soc-add-hw-dump-for-forced-rese.patch b/target/linux/generic/hack-6.12/730-net-ethernet-mtk_eth_soc-add-hw-dump-for-forced-rese.patch
index c4bf08b594b9e9fa6b9a468bf341e82b43bc3985..ffc21ee2ff7345b9c3d2a521429a0ca6eb14b0c7 100644 (file)
--- a/target/linux/generic/hack-6.12/730-net-ethernet-mtk_eth_soc-add-hw-dump-for-forced-rese.patch
+++ b/target/linux/generic/hack-6.12/730-net-ethernet-mtk_eth_soc-add-hw-dump-for-forced-rese.patch
@@ -37,7 +37,7 @@ Signed-off-by: Bo-Cun Chen <[email protected]>
                .glo_cfg        = 0x4604,
                .rst_idx        = 0x4608,
                .delay_irq      = 0x460c,
-@@ -3901,6 +3904,56 @@ static void mtk_set_mcr_max_rx(struct mt
+@@ -3909,6 +3912,56 @@ static void mtk_set_mcr_max_rx(struct mt
                mtk_w32(mac->hw, mcr_new, MTK_MAC_MCR(mac->id));
  }
  
@@ -94,7 +94,7 @@ Signed-off-by: Bo-Cun Chen <[email protected]>
  static void mtk_hw_reset(struct mtk_eth *eth)
  {
        u32 val;
-@@ -4380,6 +4433,8 @@ static void mtk_pending_work(struct work
+@@ -4388,6 +4441,8 @@ static void mtk_pending_work(struct work
        rtnl_lock();
        set_bit(MTK_RESETTING, &eth->state);
  

diff --git a/target/linux/generic/hack-6.6/730-net-ethernet-mtk_eth_soc-add-hw-dump-for-forced-rese.patch b/target/linux/generic/hack-6.6/730-net-ethernet-mtk_eth_soc-add-hw-dump-for-forced-rese.patch
index 95a6aa8cb82b41680a488b96bc2a495fef187b80..25d824bce67f811298af28623479abc46cc9f2db 100644 (file)
--- a/target/linux/generic/hack-6.6/730-net-ethernet-mtk_eth_soc-add-hw-dump-for-forced-rese.patch
+++ b/target/linux/generic/hack-6.6/730-net-ethernet-mtk_eth_soc-add-hw-dump-for-forced-rese.patch
@@ -37,7 +37,7 @@ Signed-off-by: Bo-Cun Chen <[email protected]>
                .glo_cfg        = 0x4604,
                .rst_idx        = 0x4608,
                .delay_irq      = 0x460c,
-@@ -3899,6 +3902,56 @@ static void mtk_set_mcr_max_rx(struct mt
+@@ -3907,6 +3910,56 @@ static void mtk_set_mcr_max_rx(struct mt
                mtk_w32(mac->hw, mcr_new, MTK_MAC_MCR(mac->id));
  }
  
@@ -94,7 +94,7 @@ Signed-off-by: Bo-Cun Chen <[email protected]>
  static void mtk_hw_reset(struct mtk_eth *eth)
  {
        u32 val;
-@@ -4374,6 +4427,8 @@ static void mtk_pending_work(struct work
+@@ -4382,6 +4435,8 @@ static void mtk_pending_work(struct work
        rtnl_lock();
        set_bit(MTK_RESETTING, &eth->state);
  

diff --git a/target/linux/generic/pending-6.12/742-net-ethernet-mtk_eth_soc-fix-tx-vlan-tag-for-llc-pac.patch b/target/linux/generic/pending-6.12/742-net-ethernet-mtk_eth_soc-fix-tx-vlan-tag-for-llc-pac.patch
new file mode 100644 (file)
index 0000000..20a6a29
--- /dev/null
+++ b/target/linux/generic/pending-6.12/742-net-ethernet-mtk_eth_soc-fix-tx-vlan-tag-for-llc-pac.patch
@@ -0,0 +1,39 @@
+From: Felix Fietkau <[email protected]>
+Date: Sun, 31 Aug 2025 20:05:13 +0200
+Subject: [PATCH] net: ethernet: mtk_eth_soc: fix tx vlan tag for llc packets
+
+When sending llc packets with vlan tx offload, the hardware fails to
+actually add the tag. Deal with this by fixing it up in software.
+
+Fixes: 656e705243fd ("net-next: mediatek: add support for MT7623 ethernet")
+Reported-by: Thibaut VARENE <[email protected]>
+Signed-off-by: Felix Fietkau <[email protected]>
+---
+
+--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
++++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+@@ -1778,6 +1778,13 @@ static netdev_tx_t mtk_start_xmit(struct
+       bool gso = false;
+       int tx_num;
+ 
++      if (skb_vlan_tag_present(skb) &&
++          !eth_proto_is_802_3(eth_hdr(skb)->h_proto)) {
++              skb = __vlan_hwaccel_push_inside(skb);
++              if (!skb)
++                      goto dropped;
++      }
++
+       /* normally we can rely on the stack not calling this more than once,
+        * however we have 2 queues running on the same ring so we need to lock
+        * the ring access
+@@ -1841,8 +1848,9 @@ static netdev_tx_t mtk_start_xmit(struct
+ 
+ drop:
+       spin_unlock(&eth->page_lock);
+-      stats->tx_dropped++;
+       dev_kfree_skb_any(skb);
++dropped:
++      stats->tx_dropped++;
+       return NETDEV_TX_OK;
+ }
+ 

diff --git a/target/linux/generic/pending-6.6/742-net-ethernet-mtk_eth_soc-fix-tx-vlan-tag-for-llc-pac.patch b/target/linux/generic/pending-6.6/742-net-ethernet-mtk_eth_soc-fix-tx-vlan-tag-for-llc-pac.patch
new file mode 100644 (file)
index 0000000..7e90a79
--- /dev/null
+++ b/target/linux/generic/pending-6.6/742-net-ethernet-mtk_eth_soc-fix-tx-vlan-tag-for-llc-pac.patch
@@ -0,0 +1,39 @@
+From: Felix Fietkau <[email protected]>
+Date: Sun, 31 Aug 2025 20:05:13 +0200
+Subject: [PATCH] net: ethernet: mtk_eth_soc: fix tx vlan tag for llc packets
+
+When sending llc packets with vlan tx offload, the hardware fails to
+actually add the tag. Deal with this by fixing it up in software.
+
+Fixes: 656e705243fd ("net-next: mediatek: add support for MT7623 ethernet")
+Reported-by: Thibaut VARENE <[email protected]>
+Signed-off-by: Felix Fietkau <[email protected]>
+---
+
+--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
++++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+@@ -1773,6 +1773,13 @@ static netdev_tx_t mtk_start_xmit(struct
+       bool gso = false;
+       int tx_num;
+ 
++      if (skb_vlan_tag_present(skb) &&
++          !eth_proto_is_802_3(eth_hdr(skb)->h_proto)) {
++              skb = __vlan_hwaccel_push_inside(skb);
++              if (!skb)
++                      goto dropped;
++      }
++
+       /* normally we can rely on the stack not calling this more than once,
+        * however we have 2 queues running on the same ring so we need to lock
+        * the ring access
+@@ -1836,8 +1843,9 @@ static netdev_tx_t mtk_start_xmit(struct
+ 
+ drop:
+       spin_unlock(&eth->page_lock);
+-      stats->tx_dropped++;
+       dev_kfree_skb_any(skb);
++dropped:
++      stats->tx_dropped++;
+       return NETDEV_TX_OK;
+ }
+