[PATCH net-next] net: More vlan tests before registering netdevice

[Yuval Mintz <Yuval.Mintz@qlogic.com>]

When register_netdevice() is called, netdevice's vlan filtering feature
and supplied callbacks are checked to see the vlan implementation is
not buggy.
This adds an additional test - see that the vlan_features were filled
correctly, as the vlan devices inherits those as its own features;
Incorrect values set there would later prevent the vlan interface from being
registered itself [as it doesn't implement the filtering ndos].

Signed-off-by: Yuval Mintz <Yuval.Mintz@qlogic.com>
---
Hi Dave,

Not sure why take such a defensive approach regarding this feature.
Perhaps it would have been better to simply remove these checks altogether.

Cheers,
Yuval
---

 net/core/dev.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/net/core/dev.c b/net/core/dev.c
index 3f191da..8a663b2 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -6253,10 +6253,11 @@ int register_netdevice(struct net_device *dev)
 		}
 	}
 
-	if (((dev->hw_features | dev->features) &
-	     NETIF_F_HW_VLAN_CTAG_FILTER) &&
-	    (!dev->netdev_ops->ndo_vlan_rx_add_vid ||
-	     !dev->netdev_ops->ndo_vlan_rx_kill_vid)) {
+	if ((((dev->hw_features | dev->features) &
+	      NETIF_F_HW_VLAN_CTAG_FILTER) &&
+	     (!dev->netdev_ops->ndo_vlan_rx_add_vid ||
+	      !dev->netdev_ops->ndo_vlan_rx_kill_vid)) ||
+	    (dev->vlan_features & NETIF_F_HW_VLAN_CTAG_FILTER) {
 		netdev_WARN(dev, "Buggy VLAN acceleration in driver!\n");
 		ret = -EINVAL;
 		goto err_uninit;
-- 
1.9.3