TSO, SMP and the em driver.

[John Baldwin]

On Tuesday 12 September 2006 19:14, Andre Oppermann wrote:
> Mike Tancsa wrote:
> > At 12:43 PM 9/12/2006, Andre Oppermann wrote:
> > 
> >> TSO != (vlan && promisc)
> > 
> > Sorry, the commonality I was referring to was VLAN hardware tagging and 
> > how it must be enabled for TSO, but that breaks other things.  See a few 
> > messages ago
> > 
http://lists.freebsd.org/pipermail/freebsd-current/2006-September/065818.html 
> 
> I'm sure we can find a workaround for that.

Well, you could have the em(4) driver manually handle TSO in software, which 
is what it does to workaround the VLAN tag problem.  (It does VLAN 
encapsulation in the driver.)  While VLAN insertion may be trivial, 
re-implementing TCP segmentation in the driver might be a good bit less 
trivial to do.  There's not going to be a simple easy workaround for this 
hardware bug. :(

-- 
John Baldwin