[PATCH net-next v3 2/4] net: Add a netdev software feature set that defaults to off.

[Steffen Klassert <steffen.klassert@secunet.com>]

The previous patch added the NETIF_F_GRO_FRAGLIST feature.
This is a software feature that should default to off.
Current software features default to on, so add a new
feature set that defaults to off.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
---
 include/linux/netdev_features.h | 3 +++
 net/core/dev.c                  | 2 +-
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/include/linux/netdev_features.h b/include/linux/netdev_features.h
index b239507da2a0..34d050bb1ae6 100644
--- a/include/linux/netdev_features.h
+++ b/include/linux/netdev_features.h
@@ -230,6 +230,9 @@ static inline int find_next_netdev_feature(u64 feature, unsigned long start)
 /* changeable features with no special hardware requirements */
 #define NETIF_F_SOFT_FEATURES	(NETIF_F_GSO | NETIF_F_GRO)
 
+/* Changeable features with no special hardware requirements that defaults to off. */
+#define NETIF_F_SOFT_FEATURES_OFF	NETIF_F_GRO_FRAGLIST
+
 #define NETIF_F_VLAN_FEATURES	(NETIF_F_HW_VLAN_CTAG_FILTER | \
 				 NETIF_F_HW_VLAN_CTAG_RX | \
 				 NETIF_F_HW_VLAN_CTAG_TX | \
diff --git a/net/core/dev.c b/net/core/dev.c
index 6368c94c9e0a..0dcabd3753d9 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -9272,7 +9272,7 @@ int register_netdevice(struct net_device *dev)
 	/* Transfer changeable features to wanted_features and enable
 	 * software offloads (GSO and GRO).
 	 */
-	dev->hw_features |= NETIF_F_SOFT_FEATURES;
+	dev->hw_features |= (NETIF_F_SOFT_FEATURES | NETIF_F_SOFT_FEATURES_OFF);
 	dev->features |= NETIF_F_SOFT_FEATURES;
 
 	if (dev->netdev_ops->ndo_udp_tunnel_add) {
-- 
2.17.1