Bug 2187733

Summary: vhost interface packet size reporting
Product: Red Hat Enterprise Linux Fast Datapath Reporter: Kevin Traynor <ktraynor>
Component: openvswitch3.1Assignee: Maxime Coquelin <maxime.coquelin>
Status: ASSIGNED --- QA Contact: Jiying Qiu <jiqiu>
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Version: FDP 23.BCC: ctrautma, dmarchan, jhsiao, mhou, ralongi
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Description Kevin Traynor 2023-04-18 14:46:06 UTC 
Description of problem:
As per https://www.rfc-editor.org/rfc/rfc2819.html stats for packet size are reported "including FCS".

However in DPDK vhost the packet size is being reported without an FCS which leads to a 4 byte offset in stat value. This means that packets near a boundary may be counted in the wrong packet size bucket.

It also means that for a PVP test using 64 byte packets from the traffic gen, the packets are being reported from vhost as 60 byte packets which increments the undersize pkts counters that is then reported in OVS stats.

This issue reported in https://bugzilla.redhat.com/show_bug.cgi?id=2175079#c10

Version-Release number of selected component (if applicable):
DPDK 22.11 (OVS 3.1)

Steps to Reproduce:
1. Setup PVP test with 64 byte packets
2. Check OVS vhost stats for undersize packets