Intel 82550 Pro/100 Ethernet and TSO troubles

[YongHyeon PYUN]

On Sun, Dec 18, 2011 at 08:10:20PM +0100, Andrea Venturoli wrote:
> On 12/16/11, Eugene Grosbein wrote:
> 
> (Sorry Eugene, I didn't get your message until I searched the web).
> 
> > Do you use NAT? man ipfw clearly states:
> >
> >     ipfw nat is not compatible with
> >     the TCP segmentation offloading (TSO).  Thus, to reliably nat 
> your net-
> >     work traffic, please disable TSO on your NICs using ifconfig(8)
> 
> Yes, I'm using ipfw and NAT, so this is the problem.
> Thanks for solving me this.
> 
> I'm just wondering if it was a good idea to enable TSO by default 
> without at least a warning in the release notes or in UPDATING.
> This has caused me some headaches, which is ok, I'm just sorry I've also 
> wasted some of YongHyeon's time; what's worse, I believe I won't be the 

That's fine.  This made me re-read fxp(4) TSO path and I was able
to identify possible flaw in the implementation.
Will commit the fix.

> only one hit by this.
> 
>  bye & Thanks
> 	av.