[Intel-wired-lan] [next PATCH S51-V2 1/8] i40e: Be much more verbose about what we can and cannot offload

[Bowers, AndrewX]

> -----Original Message-----
> From: Intel-wired-lan [mailto:intel-wired-lan-bounces at lists.osuosl.org] On
> Behalf Of Bimmy Pujari
> Sent: Tuesday, October 25, 2016 4:09 PM
> To: intel-wired-lan at lists.osuosl.org
> Subject: [Intel-wired-lan] [next PATCH S51-V2 1/8] i40e: Be much more
> verbose about what we can and cannot offload
> 
> From: Alexander Duyck <alexander.h.duyck at intel.com>
> 
> This change makes it so that we are much more robust about defining what
> we can and cannot offload.  Previously we were just checking for the L4
> tunnel header length, however there are other fields we should be verifying
> as there are multiple scenarios in which we cannot perform hardware
> offloads.
> 
> In addition the device only supports GSO as long as the MSS is 64 or greater.
> We were not checking this so an MSS less than that was resulting in Tx hangs.
> 
> Signed-off-by: Alexander Duyck <alexander.h.duyck at intel.com>
> Change-ID: I5e2fd5f3075c73601b4b36327b771c64fcb6c31b
> ---
> Testing Hints:
>         This is half of the fix needed to address MSS less than 64.  This
>         is the fix for upstream and kernels after 3.18.4, but we will need
>         to come up with a separate fix for out-of-tree that can be stripped
>         on kernels prior to 3.18.4.
> 
>         An easy test for this patch is to just set the MTU for an interface
>         to a value 102.  Without this patch we should see Tx hangs with
>         netperf and with we should be able to pass traffic without
>         triggering Tx hangs.
> 
>  drivers/net/ethernet/intel/i40e/i40e_main.c | 52
> ++++++++++++++++++++++++-----
>  1 file changed, 44 insertions(+), 8 deletions(-)

Tested-by: Andrew Bowers <andrewx.bowers at intel.com>
No TX Hangs with MTU 102