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Date: Fri, 22 Aug 2008 22:43:39 +0100
From: "Bruce M. Simpson" <bms@FreeBSD.org>
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Cc: Luigi Rizzo <rizzo@iet.unipi.it>, net@FreeBSD.org
Subject: Re: Small patch to multicast code...
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gnn@FreeBSD.org wrote:
> Somehow the data that the device needs to do the proper checksum
> offload is getting trashed here.  Now, since it's clear we need a
> writable packet structure so that we don't trash the original, I'm
> wondering if the m_pullup() will be sufficient.
>   

If it's serious enough to break UDP checksumming on the wire, perhaps we 
should just swallow the mbuf allocator heap churn and do the m_dup() for 
now, but slap in a big comment about why it's there.

BMS