Subject: Re: tap/bridge: Dropping NETIF_F_GSO/NETIF_F_SG

From: "Michael S. Tsirkin" <[email-masked]>
Date: Mon, 16 May 2011 12:48:21 +0300

On Mon, May 16, 2011 at 07:38:22PM +1000, Herbert Xu wrote:
> On Mon, May 16, 2011 at 11:18:41AM +0300, Michael S. Tsirkin wrote:
> >
> > There's no interface for userspace to enable it: userspace
> > only has an ioctl to enable/disable checksum offloading.
> > SG is an implementation detail.
> 
> Yes there is: ethtool -K
> 
> Cheers,

Ok. You are right of course, I was confused.

So it's just an info message: in the end if userspace DTRT features
get enabled properly. Functionally, there is no regression.

Both bridge and tun trigger the messages ATM. I note that
dev.c takes pains to avoid these messages:
	Avoid warning from netdev_fix_features() for GSO without SG

Should all drivers do this: clear _SG if they clear checksum?  What about _GSO?
If we start doing this, this spills info about flag dependencies out to drivers.

-- 
MST