Re: Misuse of LRO, how widespread

[Ben Hutchings <bhutchings@solarflare.com>]

On Mon, 2010-12-06 at 15:05 -0800, Dimitris Michailidis wrote:
> Stephen Hemminger wrote:
> > On Mon, 06 Dec 2010 13:15:42 -0800
> > Dimitris Michailidis <dm@chelsio.com> wrote:
> > 
> >> Stephen Hemminger wrote:
> >>> I inspected all drivers in net-next to see which drivers are using
> >>> LRO and which ones are broken. Most concerning is that Chelsio
> >>> and Solarflare drivers ignore ETH_FLAG_LRO.
> >>>
> >>> The ones that are using LRO but allow disabling it:
> >>>   qlcnic, netxen, mv643, s2io, myi10ge, bnx2x, ixgbe, vmxnet3
> >>>
> >>> One driver seems confused about LRO vs GRO:
> >>>   mlx4 - comments about LRO and depends on LRO but driver is using GRO
> >>>
> >>> Drivers with not using ethtool interface to disable LRO:
> >>>   pasemi_mac, sfc, ehea, cxgb3, cxgb4
> >> cxgb4 uses GRO, not LRO.
> > 
> > Ok. but cxgb3 still uses LRO (or it least calls it lro).
> > 
> 
> cxgb3 was the driver Herbert implemented GRO on I think, and he converted it 
> to GRO.  It possibly has leftover LRO references as it was using LRO before.

There's a fair amount of code setting LRO flags in various structures,
so either the driver still enables LRO in hardware/firmware or this is
dead code.

Ben.

-- 
Ben Hutchings, Senior Software Engineer, Solarflare Communications
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.