--- /dev/null
+From ffe387740bbe88dd88bbe04d6375902708003d6e Mon Sep 17 00:00:00 2001
+From: Felix Fietkau <nbd@nbd.name>
+Date: Fri, 7 Jul 2017 17:25:00 +0200
+Subject: net: add packet mangeling
+
+ar8216 switches have a hardware bug, which renders normal 802.1q support
+unusable. Packet mangling is required to fix up the vlan for incoming
+packets.
+
+Signed-off-by: Felix Fietkau <nbd@nbd.name>
+---
+ include/linux/netdevice.h | 11 +++++++++++
+ include/linux/skbuff.h | 14 ++++----------
+ net/Kconfig | 6 ++++++
+ net/core/dev.c | 20 +++++++++++++++-----
+ net/core/skbuff.c | 17 +++++++++++++++++
+ net/ethernet/eth.c | 6 ++++++
+ 6 files changed, 59 insertions(+), 15 deletions(-)
+
+--- a/include/linux/netdevice.h
++++ b/include/linux/netdevice.h
+@@ -1618,6 +1618,7 @@ enum netdev_priv_flags {
+ IFF_FAILOVER_SLAVE = 1<<28,
+ IFF_L3MDEV_RX_HANDLER = 1<<29,
+ IFF_LIVE_RENAME_OK = 1<<30,
++ IFF_NO_IP_ALIGN = 1<<31,
+ };
+
+ #define IFF_802_1Q_VLAN IFF_802_1Q_VLAN
+@@ -1650,6 +1651,7 @@ enum netdev_priv_flags {
+ #define IFF_FAILOVER_SLAVE IFF_FAILOVER_SLAVE
+ #define IFF_L3MDEV_RX_HANDLER IFF_L3MDEV_RX_HANDLER
+ #define IFF_LIVE_RENAME_OK IFF_LIVE_RENAME_OK
++#define IFF_NO_IP_ALIGN IFF_NO_IP_ALIGN
+
+ /* Specifies the type of the struct net_device::ml_priv pointer */
+ enum netdev_ml_priv_type {
+@@ -1990,6 +1992,11 @@ struct net_device {
+ const struct tlsdev_ops *tlsdev_ops;
+ #endif
+
++#ifdef CONFIG_ETHERNET_PACKET_MANGLE
++ void (*eth_mangle_rx)(struct net_device *dev, struct sk_buff *skb);
++ struct sk_buff *(*eth_mangle_tx)(struct net_device *dev, struct sk_buff *skb);
++#endif
++
+ const struct header_ops *header_ops;
+
+ unsigned int flags;
+@@ -2080,6 +2087,10 @@ struct net_device {
+ struct mpls_dev __rcu *mpls_ptr;
+ #endif
+
++#ifdef CONFIG_ETHERNET_PACKET_MANGLE
++ void *phy_ptr; /* PHY device specific data */
++#endif
++
+ /*
+ * Cache lines mostly used on receive path (including eth_type_trans())
+ */
+--- a/include/linux/skbuff.h
++++ b/include/linux/skbuff.h
+@@ -2710,6 +2710,10 @@ static inline int pskb_trim(struct sk_bu
+ return (len < skb->len) ? __pskb_trim(skb, len) : 0;
+ }
+
++extern struct sk_buff *__netdev_alloc_skb_ip_align(struct net_device *dev,
++ unsigned int length, gfp_t gfp);
++
++
+ /**
+ * pskb_trim_unique - remove end from a paged unique (not cloned) buffer
+ * @skb: buffer to alter
+@@ -2841,16 +2845,6 @@ static inline struct sk_buff *dev_alloc_
+ }
+
+
+-static inline struct sk_buff *__netdev_alloc_skb_ip_align(struct net_device *dev,
+- unsigned int length, gfp_t gfp)
+-{
+- struct sk_buff *skb = __netdev_alloc_skb(dev, length + NET_IP_ALIGN, gfp);
+-
+- if (NET_IP_ALIGN && skb)
+- skb_reserve(skb, NET_IP_ALIGN);
+- return skb;
+-}
+-
+ static inline struct sk_buff *netdev_alloc_skb_ip_align(struct net_device *dev,
+ unsigned int length)
+ {
+--- a/net/Kconfig
++++ b/net/Kconfig
+@@ -26,6 +26,12 @@ menuconfig NET
+
+ if NET
+
++config ETHERNET_PACKET_MANGLE
++ bool
++ help
++ This option can be selected by phy drivers that need to mangle
++ packets going in or out of an ethernet device.
++
+ config WANT_COMPAT_NETLINK_MESSAGES
+ bool
+ help
+--- a/net/core/dev.c
++++ b/net/core/dev.c
+@@ -3638,11 +3638,21 @@ static int xmit_one(struct sk_buff *skb,
+ if (dev_nit_active(dev))
+ dev_queue_xmit_nit(skb, dev);
+
+- len = skb->len;
+- PRANDOM_ADD_NOISE(skb, dev, txq, len + jiffies);
+- trace_net_dev_start_xmit(skb, dev);
+- rc = netdev_start_xmit(skb, dev, txq, more);
+- trace_net_dev_xmit(skb, rc, dev, len);
++#ifdef CONFIG_ETHERNET_PACKET_MANGLE
++ if (!dev->eth_mangle_tx ||
++ (skb = dev->eth_mangle_tx(dev, skb)) != NULL)
++#else
++ if (1)
++#endif
++ {
++ len = skb->len;
++ PRANDOM_ADD_NOISE(skb, dev, txq, len + jiffies);
++ trace_net_dev_start_xmit(skb, dev);
++ rc = netdev_start_xmit(skb, dev, txq, more);
++ trace_net_dev_xmit(skb, rc, dev, len);
++ } else {
++ rc = NETDEV_TX_OK;
++ }
+
+ return rc;
+ }
+--- a/net/core/skbuff.c
++++ b/net/core/skbuff.c
+@@ -60,6 +60,7 @@
+ #include <linux/prefetch.h>
+ #include <linux/if_vlan.h>
+ #include <linux/mpls.h>
++#include <linux/if.h>
+
+ #include <net/protocol.h>
+ #include <net/dst.h>
+@@ -553,6 +554,22 @@ skb_fail:
+ }
+ EXPORT_SYMBOL(__napi_alloc_skb);
+
++struct sk_buff *__netdev_alloc_skb_ip_align(struct net_device *dev,
++ unsigned int length, gfp_t gfp)
++{
++ struct sk_buff *skb = __netdev_alloc_skb(dev, length + NET_IP_ALIGN, gfp);
++
++#ifdef CONFIG_ETHERNET_PACKET_MANGLE
++ if (dev && (dev->priv_flags & IFF_NO_IP_ALIGN))
++ return skb;
++#endif
++
++ if (NET_IP_ALIGN && skb)
++ skb_reserve(skb, NET_IP_ALIGN);
++ return skb;
++}
++EXPORT_SYMBOL(__netdev_alloc_skb_ip_align);
++
+ void skb_add_rx_frag(struct sk_buff *skb, int i, struct page *page, int off,
+ int size, unsigned int truesize)
+ {
+--- a/net/ethernet/eth.c
++++ b/net/ethernet/eth.c
+@@ -171,6 +171,12 @@ __be16 eth_type_trans(struct sk_buff *sk
+ const struct ethhdr *eth;
+
+ skb->dev = dev;
++
++#ifdef CONFIG_ETHERNET_PACKET_MANGLE
++ if (dev->eth_mangle_rx)
++ dev->eth_mangle_rx(dev, skb);
++#endif
++
+ skb_reset_mac_header(skb);
+
+ eth = (struct ethhdr *)skb->data;