Does the bonding driver honour dev->features of slave devices

[Tomar, Nagendra (nagendra_tomar@adaptec.com)]

Hello All,
	  I am going throgh the "Link Aggregation" module in Linux 
(bonding.c). The code seems to suggest that the dev->features of slave 
devices is simply ignored while bundling into the master device. Suppose I 
have two Intel epro1000 cards that can support TCP Segmentation Offload. 
Now if I bond these two slave cards into a new master card, the new 
bonding device that is the master device will be used in the routing 
table. When a TCP connection is established sk->route_caps is assigned 
from the dev->features of the assigned outgoing device. If the outgoing 
device is the bonding device then the dev->features won't have NETIF_F_TSO 
as the feature and hence upper layers will believe that the outgoing 
device cannot do TSO.
I believe that at best we can take an OR of the dev->features of all the 
slave devices and assign it to the dev->features of the bonding device. 
This way we are sure that we are taking the Least Common Denominator while 
deciding the features for the master device.

Thanx,
tomar
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