Re: [BUG] bnx2 + vlan + TSO : doesnt work

On Mon, Jan 17, 2011 at 4:09 PM, Ben Hutchings
[off-list ref] wrote:

On Tue, 2011-01-18 at 01:00 +0100, Eric Dumazet wrote:

quoted

Le lundi 17 janvier 2011 à 23:47 +0000, Ben Hutchings a écrit :

quoted

On Tue, 2011-01-18 at 00:41 +0100, Eric Dumazet wrote:

quoted

Oh well, my dev machine, with bnx2 and tg3 NICs, isnt working at all
with current linux-2.6 tree (I need vlans on my setup)

tg3 : vlan not working

bnx2 : vlan + TSO not working (or very slowly, since only non GSO frames
are OK)

I suspect recent commits from Jesse are the problem.
(bnx2_xmit() is feeded with zeroed vlan_tci skbs)

Maybe f01a5236bd4b1401 (net offloading: Generalize
netif_get_vlan_features().) ?

I dont see NETIF_F_HW_VLAN_TX being set in vlan_features in net drivers.
They only set this flag in dev->features

I dont think changing all drivers to also set vlan_features makes sense.

Is following patch the right path ? (It does solve my problem)

This isn't right.  NETIF_F_HW_VLAN_TX in vlan_features would mean that
the hardware can do two levels of VLAN tag insertion, which is generally
not true.

So should we revert part of Jesse patch ? I want my vlan back ;)

Yeah, that looks right.

I think it is better for netif_skb_features() to actually return the
correct features rather than bypass it here.  NETIF_F_HW_VLAN_TX
doesn't depend on any other offloads, so we can always include it if
it is in dev->features.

Separately, this means there is a problem with bnx2 because it allows
vlan insertion to be turned off, which would have the same effect.
Maybe it is looking directly at skb->protocol or similar for TSO.