From mboxrd@z Thu Jan  1 00:00:00 1970
From: "David S. Miller" <davem@davemloft.net>
Subject: Re: skb_checksum_help
Date: Tue, 25 Jan 2005 15:30:20 -0800
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To: Thomas Graf <tgraf@suug.ch>
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On Tue, 25 Jan 2005 22:15:24 +0100
Thomas Graf <tgraf@suug.ch> wrote:

> I thought about this too and actually implemented it but it means to
> change all relevant drivers and the only feature that might be
> driver specific is checksumming, given I didn't make any mistakes
> while checking the drivers for pskb compatibility.

It is not only checksumming, but also TSO.  TSO, like checksumming,
is a feature where the chip must parse the packet to figure out where
to do it's work.  In fact, TSO is a prime suspect for VLAN problems
as the card must duplicate the VLAN headers properly as it chops
up the TSO frame into MSS sized pieces.