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From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next 11/15]bnx2x: Add TPA, Broadcoms HW LRO
Date: Tue, 17 Jun 2008 16:16:40 -0700 (PDT)
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From: Ben Hutchings <bhutchings@solarflare.com>
Date: Tue, 17 Jun 2008 16:17:06 +0100

> Ben Hutchings wrote:
> > Eilon Greenstein wrote:
> > > The TPA stands for Transparent Packet Aggregation. When enabled, the FW
> > > aggregate in-order TCP packets according to the 4-tuple match and sends
> > > 1 big packet to the driver. This packet is stored on an SGL in which
> > > each SGE is 1 page. The FW also implements a timeout algorithm and it
> > > honors all TCP flag, including the push flag as a trigger to halt
> > > aggregation.
> > [...]
> > 
> > LRO is not compatible with forwarding and will currently trigger a BUG() or
> > WARN() if used on packets that are then forwarded.
> 
> Actually, since this implementation doesn't set gso_size in LRO'd skbs, it
> will confuse TCP in interesting ways instead.  You need to set gso_size to
> the largest segment size seen in the packets that were aggregated.

Eilon, please sort this out, thanks.