Re: [v2 Patch 2/2] mlx4: add dynamic LRO disable support

[Stanislaw Gruszka <sgruszka@redhat.com>]

On Tue, 15 Jun 2010 16:35:35 +0800
Cong Wang <amwang@redhat.com> wrote:
> > BTW: seems default ethtool_op_set_flags introduce a bug on many
> > devices regarding ETH_FLAG_RXHASH. I think default should
> > be EOPNOTSUPP, and these few devices that actually support RXHASH
> > should have custom ethtool_ops->set_flags
> 
> Hmm, you mean this?
> 
>   if (data & ETH_FLAG_RXHASH)
> +    if (!ops->set_flags)
> +        return -EOPNOTSUPP;
> ....

Not really, but I do not have good idea how patch with fix should
looks.

I dislike fact that we setup ->feature that are not in real supported by
particular device instead of returning EOPNOTSUPP. This actually include
both flags NETIF_F_LRO and NETIF_F_RXHASH. 

Perhaps ethtool_op_set_flags should be removed and drivers should use
only custom version. In particular seems e1000e and sfc use this
function improperly and should have NULL as .set_flags.

I will think more about that and maybe cook some patches.

Stanislaw