vlan: Warn the user if lowerdev has bad vlan features.
Some drivers incorrectly assign vlan acceleration features to
vlan_features thus causing issues for Q-in-Q vlan configurations.
Warn the user of such cases.
Signed-off-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/netdev_features.h b/include/linux/netdev_features.h
index 1005ebf..5a09a48 100644
--- a/include/linux/netdev_features.h
+++ b/include/linux/netdev_features.h
@@ -163,4 +163,11 @@
/* changeable features with no special hardware requirements */
#define NETIF_F_SOFT_FEATURES (NETIF_F_GSO | NETIF_F_GRO)
+#define NETIF_F_VLAN_FEATURES (NETIF_F_HW_VLAN_CTAG_FILTER | \
+ NETIF_F_HW_VLAN_CTAG_RX | \
+ NETIF_F_HW_VLAN_CTAG_TX | \
+ NETIF_F_HW_VLAN_STAG_FILTER | \
+ NETIF_F_HW_VLAN_STAG_RX | \
+ NETIF_F_HW_VLAN_STAG_TX)
+
#endif /* _LINUX_NETDEV_FEATURES_H */
diff --git a/net/8021q/vlan_dev.c b/net/8021q/vlan_dev.c
index a9591ff..27bfe2f 100644
--- a/net/8021q/vlan_dev.c
+++ b/net/8021q/vlan_dev.c
@@ -578,6 +578,9 @@
dev->features |= real_dev->vlan_features | NETIF_F_LLTX;
dev->gso_max_size = real_dev->gso_max_size;
+ if (dev->features & NETIF_F_VLAN_FEATURES)
+ netdev_warn(real_dev, "VLAN features are set incorrectly. Q-in-Q configurations may not work correctly.\n");
+
/* ipv6 shared card related stuff */
dev->dev_id = real_dev->dev_id;