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Date: Mon, 19 Sep 2011 12:32:14 -0400
From: "Dieter BSD" <dieterbsd@engineer.com>
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Subject: Re: checksum offload
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>>> The data sheet for intel 82576 advertises IP TX/RX checksum offload
>>> but the driver does not set CSUM_IP in ifp->if_hwassist. Does this mean
>>> that driver (and chip) do not support IP TX checksum offload or the
>>> support for TX is not yet included in the driver?
>>
>> The first question is "is checksum offload a good idea?"
>> There is less protection against errors.
>
> This assumes firmware flaws, right? Albeit, it also does confuse some
> software like tcpdump.

"Unfortunately lots of high performance people use checksum offload
which removes much of the end to end protection"

      Alan Cox

http://kerneltrap.org/Linux/Data_Errors_During_Drive_Communication

Bugs in the hardware/firmware/software are not required to have a
problem, but if present would make things even worse.