kern/171520: [alc] alc network driver + tso + vlan does not work.

[YongHyeon PYUN]

On Mon, Oct 22, 2012 at 10:15:28AM +0600, Nikolay Nevzorov wrote:
> 2012/10/22 Eugene Grosbein <egrosbein at rdtc.ru>
> 
> > 22.10.2012 10:55, Nikolay Nevzorov пишет:
> > > I can make clean test.
> > >
> > > What do you mean by clean:
> > > reboot with disable mpd (and so will be not enabled kernel NAT in
> > system) or remove LIBALIAS from kernel too?
> >
> > You need not reboot or disable mpd. Just make sure your testing traffic
> > does not pass through NAT.
> >
> >
> > Any traffic throuhg NAT does not cause problems. And any routed traffic so
> on.
> 
> Problem only with traffic that generated on host with alc0, because host
> generate packets much more bigger than MTU (about 2300 bytes per packet
> with MTU 1500), a see it with tcpdump on alc0.

It's completely normal to see bigger MTU sized packets on
TSO-capable controllers. bpf sees these packets *before* hardware
actually segments these packets.