Re: [net PATCH] i40e/i40evf: Limit TSO to 7 descriptors for payload instead of 8 per packet

On Wed, Mar 30, 2016 at 10:20 AM, Sowmini Varadhan
[off-list ref] wrote:

On (03/30/16 10:12), Alexander Duyck wrote:

quoted

Yeah.  The patch was sort of a knee-jerk reaction to being told that
the patch referenced caused a regression.  From what I can tell that
is not the case as I am also seeing the Tx hangs when I run the test
with the frames being linearized.

I'm not sure how important of a subtlety this is, but the actual
console log after the patch is the following:

 i40e 0000:82:00.0: TX driver issue detected, PF reset issued
 i40e 0000:82:00.0 eth2: adding 68:05:ca:30:dd:18 vid=0
 i40e 0000:82:00.0: TX driver issue detected, PF reset issued
 i40e 0000:82:00.0 eth2: adding 68:05:ca:30:dd:18 vid=0
 i40e 0000:82:00.0: TX driver issue detected, PF reset issued

Comparing with what I'd pasted in the sourceforge thread earlier,
I see that it does not say "Hung Tx queue etc."  any more, though
it still resets.

Not sure if that changed info is significant?

It might be.  Right now I am chasing down the Tx driver issue as that
I what I am reproducing in my environment as well.

From what I can tell by enabling msglvl tx_err it is reporting MDD

event 0x2.  Unfortunately the documentation doesn't say what that is
so I am checking a few different possibilities.

- Alex