From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@ftp.linux.org.uk>
Subject: Re: [PATCH] IPv6: optimize echo reply checksum calculation
Date: Fri, 10 Nov 2006 17:34:22 +0000
Message-ID: <20061110173422.GM29920@ftp.linux.org.uk>
References: <20061108221332.GI29920@ftp.linux.org.uk> <45536622.90708@hp.com> <20061109.151402.15590179.davem@davemloft.net> <4554A811.5060402@hp.com>
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Cc: David Miller <davem@davemloft.net>, netdev@vger.kernel.org
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To: Brian Haley <brian.haley@hp.com>
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On Fri, Nov 10, 2006 at 11:25:53AM -0500, Brian Haley wrote:
> Since the only difference between echo requests and echo replies is the 
> ICMPv6 type value (which is a difference of 1), just subtracting one 
> from the request checksum will result in the correct checksum for the reply.

Um, no.  That will *not* result in correct checksum.  Please, RTFRFC 1071.