[dpdk-dev] nic loopback

[Liang, Cunming]

It’s a pain VF can’t set the register directly.
As kernel ixgbe don’t support to set the value, I’m afraid you have to modify kernel ixgbe.
If your purpose is mainly for testing purpose.
One option is you can just set the register bit value to full 1 during device initialization.
Another option is you can choose to use DPDK as host PF.
Running testpmd in host, and set such register by interactive command line.

Ideally it’s better to add a kind of VF to PF mailbox message.
Host PF delegate VF to enable the local pool loopback.
So during runtime, VF can proactive to enable/disable the ability.


From: Alex Markuze [mailto:alex at weka.io]
Sent: Tuesday, October 21, 2014 11:16 PM
To: Liang, Cunming
Cc: dev at dpdk.org
Subject: Re: [dpdk-dev] nic loopback

How can I set/query this bit (LLE(PFVMTXSW[n]), intel 82599 ) on ESX, or any other friendlier environment like Linux?

On Tue, Oct 21, 2014 at 4:18 AM, Liang, Cunming <cunming.liang at intel.com<mailto:cunming.liang at intel.com>> wrote:


> -----Original Message-----
> From: dev [mailto:dev-bounces at dpdk.org<mailto:dev-bounces at dpdk.org>] On Behalf Of Alex Markuze
> Sent: Tuesday, October 21, 2014 12:24 AM
> To: dev at dpdk.org<mailto:dev at dpdk.org>
> Subject: [dpdk-dev] nic loopback
>
> Hi,
> I'm trying to send packets from an application to it self, meaning smac  ==
> dmac.
> I'm working with intel 82599 virtual function. But it seems that these
> packets are lost.
>
> Is there a software/hw limitation I'm missing here (some additional
> anti-spoofing)? AFAIK modern NICs with sriov are mini switches so the hw
> loopback should work, at least thats the theory.
>
[Liang, Cunming] You could have a check on register LLE(PFVMTXSW[n]).
Which allow an individual pool to be able to send traffic and have it loopback to itself.
>
> Thanks.