Re: [PATCH 05/34]bnx2x: Setting the GSO_TYPE with LRO

[Ben Hutchings <bhutchings@solarflare.com>]

On Thu, 2009-01-15 at 07:18 +1100, Herbert Xu wrote:
> Eilon Greenstein <eilong@broadcom.com> wrote:
> >> 
> > This is far from bullet proof solution, but IMHO it is better set then
> > not  this way, you stand a chance (depending on the output device
> > capabilities)
> 
> The question is simple, does your hardware guarantee that on
> output GSO will turn the packet into exactly the same sequence
> of packets that was seen on input, with no changes (apart from
> what the stack would have done to them anyway, e.g., TTL update)
> whatsoever?
> 
> If not then you mustn't set this and also you must disable it
> if forwarding/bridging is used.

The driver just has to cooperate with dev_disable_lro() in order for the
forwarding/bridging code to disable it.  Then skb_warn_if_lro() should
catch the case where the user mistakenly turns it back on.  However,
setting gso_type on input subverts this check.

Ben.

-- 
Ben Hutchings, Senior Software Engineer, Solarflare Communications
Not speaking for my employer; that's the marketing department's job.
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