Re: [net-next 02/16] i40e/i40evf: Rewrite logic for 8 descriptor per packet check

On Tue, 2016-03-29 at 22:19 -0700, Alexander Duyck wrote:

Minor correction here.  This is 72 hex, which is 114 in decimal.  The
interesting bit I believe is the fact that we have both header and
payload data in the same descriptor.

You should probably check with your hardware team on this but I have
a
working theory on the issue.  I'm thinking that because both header
and payload are coming out of the same descriptor this must count as
2
descriptors and not 1 when we compute the usage for the first
descriptor.  As such I do probably need to start testing at frag 0
because the first payload can actually come out of the header region
if the first descriptor includes both payload and data.

I'll try to submit a patch for it tonight.  If you can test it
tomorrow I would appreciate it.  Otherwise I will try setting up an
environment to try and reproduce the issue tomorrow.

If you get it submitted tonight, I can have it ready in my tree for
testing for Jesse and the team when they get into the office tomorrow.