From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Hemminger <shemminger@vyatta.com>
Subject: Re: Netxen packet loss with VLANs and LRO (was: [PATCH] netxen: fix
 LRO disable warning)
Date: Tue, 5 Apr 2011 08:46:55 -0700
Message-ID: <20110405084655.10937250@nehalam>
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	<20110405151854.GA32759@torres.zugschlus.de>
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Cc: Amit Salecha <amit.salecha@qlogic.com>,
	"davem@davemloft.net" <davem@davemloft.net>,
	"netdev@vger.kernel.org" <netdev@vger.kernel.org>,
	Ameen Rahman <ameen.rahman@qlogic.com>,
	Rajesh Borundia <rajesh.borundia@qlogic.com>
To: Marc Haber <mh+netdev@zugschlus.de>
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On Tue, 5 Apr 2011 17:18:54 +0200
Marc Haber <mh+netdev@zugschlus.de> wrote:

> On Tue, Apr 05, 2011 at 08:15:16AM -0500, Amit Salecha wrote:
> > This will fix LRO configuration problem. Do you see packet loss with
> > LRO disable ?
> 
> No, with LRO disabled things seem to be fine. LRO gets enabled by
> default though.

LRO and routing are fundamentally incompatible, that is why
the kernel attempts to turn it off. When forwarding packets
should not be combined (end-to-end principle) and that is what
LRO does.

Therefore if doing anything like bridging or forwarding kernel
attempts to get driver to turn LRO off.