X720 and jumbo frame

[hirokazutakahashi]

Issue Type

• Bug report
• Feature proposal

Summary

Jumbo frames can't be handled by x720(i40e).

Bug report

I configured Lagopus with "--enable-jumbo-frame" and put "-mtu 2048" to the configuration file.
Then the console log says
i40e_dev_interrupt_handler(): ICR0: malicious programming detected.
Then the Lagopus does not forward any packets and does not count up tx counters.

With x520(ixgbe), It works fine.

Expected behavior

Lagopus can handle jumbo frames correctly.

Actual behavior

As the "Bug report" above.

Environment

master branch.
Ubuntu 16.04LTS.
x86 server.

Steps to reproduce

As the "Bug report" above.

Relevant logs

As the "Bug report" above.

Component

Dataplane.

Possible fixes

I will try to inspect and report it.

[iMasaruOki]

Do you use which version of lagopus (DPDK)?

[hirokazutakahashi]

Acrually, I'm using forked version of lagopus.
https://github.com/hirokazutakahashi/lagopus/commits/shownet

The branch is the current master branch of lagopus and some fixes.
I think the fixes don't affect the jumbo frame handling.

I'll try with the current master.

[slankdev]

I know a similar problem when sending 9K JumboFrame with dpdk v17.11
(I tried connectx-5, x710, x540).

One of the answers to send JumboFrame is configuring with enable_scatter bit.
This bit enables sending the scattered packets (such as multi-segmented mbuf).
Probably, The enable_scatter bit is needed to send scattered packet is not discussed in dpdk official documentation (dpdk.org).

• http://dpdk.org/doc/api/structrte__eth__rxmode.html#a1cb4dbcf9775db5b6ec710ba849572fa

But, the same problem was occurred. :(
So currently, I am dealing with the Larger-Data-Room mbuf. (call rte_pktmbuf_pool_create() with data_room_size=9K)

• rte_pktmbuf_pool_create
  http://dpdk.org/doc/api/rte__mbuf_8h.html#a593921f13307803b94bbb4e0932db962

[iMasaruOki]

Thank you. Your 'shownet' branch uses DPDK 18.02.
I read i40e_dev_mtu_set() in DPDK 18.02.

MTU setting on running i40e NIC causes EBUSY.
Correct sequence I think:

1. link down
2. set MTU
3. link up

Sure, is ist correct?