mlx5: become aware of when running as a bonding slave

I've been unable to get my hands on suitable supported hardware to date,
but I believe this ought to be all that is needed to enable the mlx5
driver to also work with bonding active-backup crypto offload passthru.

CC: Boris Pismenny <[email protected]>
CC: Saeed Mahameed <[email protected]>
CC: Leon Romanovsky <[email protected]>
CC: Jay Vosburgh <[email protected]>
CC: Veaceslav Falico <[email protected]>
CC: Andy Gospodarek <[email protected]>
CC: "David S. Miller" <[email protected]>
CC: Jeff Kirsher <[email protected]>
CC: Jakub Kicinski <[email protected]>
CC: Steffen Klassert <[email protected]>
CC: Herbert Xu <[email protected]>
CC: [email protected]
Signed-off-by: Jarod Wilson <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec.c

@@ -210,6 +210,9 @@ static inline int mlx5e_xfrm_validate_state(struct xfrm_state *x)
 	struct net_device *netdev = x->xso.dev;
 	struct mlx5e_priv *priv;
 
+	if (x->xso.slave_dev)
+		netdev = x->xso.slave_dev;
+
 	priv = netdev_priv(netdev);
 
 	if (x->props.aalgo != SADB_AALG_NONE) {
@@ -291,6 +294,9 @@ static int mlx5e_xfrm_add_state(struct xfrm_state *x)
 	unsigned int sa_handle;
 	int err;
 
+	if (x->xso.slave_dev)
+		netdev = x->xso.slave_dev;
+
 	priv = netdev_priv(netdev);
 
 	err = mlx5e_xfrm_validate_state(x);