Description of problem:

Call failure and packet drop occurred in OCP 4.8.

And after upgrading the cluster to 4.9:
  - Packet drop judged to be caused by upcall is not found
  - Call failure occurred under any conditions until 4/8, but did not occur after 4/11.
  - Unconfirmed any difference between 4/8 and 4/11

Result when applying OVN controller pause
  - 200ms delay does not occur
  - Upcall does not occur, but Out of Order still occurs

The above result was confirmed under the following circumstances
1) Pod etho <---> Out of order occurs when ovs receives a packet sent by pod between ovs interface
2) When an out of order occurs between genev interface <---> genev interface
In both cases, 200ms delay did not occur, and after requesting DUP_ACK 5 times or less, reordering was processed without retransmission.

Result when applying OVN controller turn on
  - '200ms delay' by Out-of-Order occurs again
  - Currently, call failure does not occur in both OVN controller turn on/pause, so it is not possible to determine whether it is related.

Version-Release number of selected component (if applicable):

- OCP 4.9.23(ovn-kubernetes)
- baremetal 
- IPv6

How reproducible:


Steps to Reproduce:
1.
2.
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Actual results:

When the reproducibility test is performed, '200ms delay' due to Out of Order occurs.


Expected results:

Find out why there are a lot of upcalls in 'OVN controller turn on' and there should be no '200ms delay'


Additional info: