Comment 3 for bug 2067889

After that one knows which sub-log to check, for ease of consumption
I've attached the subsection here that talks about the actually failing tests.

Fail #1
/tmpdir/_debian/tests/system-dpdk-testsuite.dir/004/cleanup: line 1: kill: (275003) - No such process
4. system-dpdk.at:102: 4. OVS-DPDK - ping vhost-user ports (system-dpdk.at:102): FAILED (system-dpdk.at:148)

Fail #2
> 2024-05-31T10:08:11.896Z|00087|dpdk|INFO|VHOST_CONFIG: (/tmpdir/_debian/tests/system-dpdk-testsuite.dir/005/dpdkvhostclient0) free connfd 52
> 2024-05-31T10:08:11.896Z|00088|netdev_dpdk|INFO|vHost Device '/tmpdir/_debian/tests/system-dpdk-testsuite.dir/005/dpdkvhostclient0' not found
tests/system-dpdk-testsuite: line 1754: 275274 Killed dpdk-testpmd $eal_options -- $testpmd_options > testpmd.log 2>&1
5. system-dpdk.at:158: 5. OVS-DPDK - ping vhost-user-client ports (system-dpdk.at:158): FAILED (system-dpdk.at:224)

Fail #3
> 2024-05-31T10:08:17.179Z|00120|dpdk|INFO|VHOST_CONFIG: (/tmpdir/_debian/tests/system-dpdk-testsuite.dir/016/dpdkvhostclient0) free connfd 52
> 2024-05-31T10:08:17.179Z|00121|netdev_dpdk|INFO|vHost Device '/tmpdir/_debian/tests/system-dpdk-testsuite.dir/016/dpdkvhostclient0' not found
tests/system-dpdk-testsuite: line 1754: 275495 Killed dpdk-testpmd $eal_options -- $testpmd_options > testpmd.log 2>&1
16. system-dpdk.at:577: 16. OVS-DPDK - MTU increase vport port (system-dpdk.at:577): FAILED (system-dpdk.at:609)

Fail #4
> 2024-05-31T10:08:22.436Z|00079|dpdk|INFO|VHOST_CONFIG: (/tmpdir/_debian/tests/system-dpdk-testsuite.dir/017/dpdkvhostclient0) free connfd 52
> 2024-05-31T10:08:22.436Z|00080|netdev_dpdk|INFO|vHost Device '/tmpdir/_debian/tests/system-dpdk-testsuite.dir/017/dpdkvhostclient0' not found
tests/system-dpdk-testsuite: line 1767: 275658 Killed dpdk-testpmd $eal_options -- $testpmd_options > testpmd.log 2>&1
17. system-dpdk.at:618: 17. OVS-DPDK - MTU decrease vport port (system-dpdk.at:618): FAILED (system-dpdk.at:651)

Fail #5
> 2024-05-31T10:08:28.375Z|00121|dpdk|INFO|VHOST_CONFIG: (/tmpdir/_debian/tests/system-dpdk-testsuite.dir/020/dpdkvhostclient0) free connfd 52
> 2024-05-31T10:08:28.375Z|00122|netdev_dpdk|INFO|vHost Device '/tmpdir/_debian/tests/system-dpdk-testsuite.dir/020/dpdkvhostclient0' not found
tests/system-dpdk-testsuite: line 1754: 275858 Killed dpdk-testpmd $eal_options -- $testpmd_options > testpmd.log 2>&1
20. system-dpdk.at:736: 20. OVS-DPDK - MTU upper bound vport port (system-dpdk.at:736): FAILED (system-dpdk.at:767)

Fail #6
> 2024-05-31T10:08:32.113Z|00079|dpdk|INFO|VHOST_CONFIG: (/tmpdir/_debian/tests/system-dpdk-testsuite.dir/021/dpdkvhostclient0) free connfd 52
> 2024-05-31T10:08:32.113Z|00080|netdev_dpdk|INFO|vHost Device '/tmpdir/_debian/tests/system-dpdk-testsuite.dir/021/dpdkvhostclient0' not found
tests/system-dpdk-testsuite: line 1767: 276061 Killed dpdk-testpmd $eal_options -- $testpmd_options > testpmd.log 2>&1
21. system-dpdk.at:778: 21. OVS-DPDK - MTU lower bound vport port (system-dpdk.at:778): FAILED (system-dpdk.at:809)

They seem to all stumble over some cleanup.
The question now is if that is a symptom (something before goes wrong, and then
we see the cleanup path go nuts). Or if it is the root cause (it always cleaned
up, but now it no more works).

It seems the sequence here is always to the end of the actual tests.
There it deletes interfaces, but then breaks on the associated file not existing.
But is that really the issue that changed?