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Subject: Re: PROBLEM: Silent data corruption when using sendfile()
From: Eric Dumazet <eric.dumazet@gmail.com>
To: Hillf Danton <dhillf@gmail.com>
Cc: Johannes Truschnigg <johannes@truschnigg.info>,
        linux-kernel@vger.kernel.org, Willy Tarreau <w@1wt.eu>,
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Date: Sat, 14 Jul 2012 16:19:00 +0200
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On Sat, 2012-07-14 at 22:08 +0800, Hillf Danton wrote:
> On Sat, Jul 14, 2012 at 4:20 PM, Eric Dumazet <eric.dumazet@gmail.com> wrote:
> >
> > Might be, or not (could be a NIC bug)
> >
> Dunno why sendfile sits in the layer of NIC and
> how they interact.

sendfile() relies heavily on TSO capabilities, a buggy NIC could
corrupt frame content on some obscure occasions.

We had some known cases on IPv6 for example.