From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Hemminger <shemminger@vyatta.com>
Subject: Re: [PATCH 0/7] via-velocity performance fixes
Date: Mon, 23 Nov 2009 08:27:08 -0800
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Cc: netdev@vger.kernel.org, davem@davemloft.net, davej@redhat.com,
	romieu@fr.zoreil.com
To: Simon Kagstrom <simon.kagstrom@netinsight.net>
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On Mon, 23 Nov 2009 14:39:22 +0100
Simon Kagstrom <simon.kagstrom@netinsight.net> wrote:

> while the VIA driver does
> 
> 	ip_summed = CHECKSUM_NONE;
> 	if (hardware sees that this is an IP packet):
> 		if (hw IP checksum is OK):
> 			if (hw sees that this is a TCP/UDP packet):
> 				if (hw TCP/UDP checksum is NOT OK):
> 					return  # Returning CHECKSUM_NONE
> 				ip_summed = CHECKSUM_UNNECESSARY
> 
> i.e., it will return CHECKSUM_NONE also for non-TCP/UDP IP packets.

That is correct assuming hardware can only checksum TCP/UDP.

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