ubuntu_kernel_selftests:net:veth.sh: Failing with too many packets received

[Stefan Bader]

First observed while reviewing focal:linux-hwe-5.13 on entei(ppc64el) for sru-20211018. This seems to be a new test for 5.13 kernels. I cannot recall having seen it before.

19:39:22 DEBUG| [stdout] # selftests: net: veth.sh
19:39:22 DEBUG| [stdout] # default - gro flag ok
19:39:22 DEBUG| [stdout] # - peer gro flag ok
19:39:22 DEBUG| [stdout] # - tso flag ok
19:39:22 DEBUG| [stdout] # - peer tso flag ok
19:39:22 DEBUG| [stdout] # - aggregation ok
19:39:22 DEBUG| [stdout] # - aggregation with TSO off ok
19:39:22 DEBUG| [stdout] # with gro on - gro flag ok
19:39:22 DEBUG| [stdout] # - peer gro flag ok
19:39:22 DEBUG| [stdout] # - tso flag ok
19:39:22 DEBUG| [stdout] # - peer tso flag ok
19:39:22 DEBUG| [stdout] # - aggregation with TSO off fail - got 10 packets, expected 1
19:39:23 DEBUG| [stdout] # with gro enabled on link down - gro flag ok
19:39:23 DEBUG| [stdout] # - peer gro flag ok
19:39:23 DEBUG| [stdout] # - tso flag ok
19:39:23 DEBUG| [stdout] # - peer tso flag ok
19:39:23 DEBUG| [stdout] # - aggregation with TSO off fail - got 10 packets, expected 1
19:39:23 DEBUG| [stdout] # with xdp attached - gro flag ok
19:39:23 DEBUG| [stdout] # - peer gro flag ok
19:39:23 DEBUG| [stdout] # - tso flag ok
19:39:23 DEBUG| [stdout] # - peer tso flag ok
19:39:23 DEBUG| [stdout] # - aggregation fail - got 10 packets, expected 1
19:39:23 DEBUG| [stdout] # - after dev off, flag ok
19:39:23 DEBUG| [stdout] # - peer flag ok
19:39:23 DEBUG| [stdout] # - after gro on xdp off, gro flag ok
19:39:23 DEBUG| [stdout] # - peer gro flag ok
19:39:23 DEBUG| [stdout] # - tso flag ok
19:39:23 DEBUG| [stdout] # - peer tso flag ok
19:39:23 DEBUG| [stdout] # - aggregation ok
19:39:23 DEBUG| [stdout] # aggregation again with default and TSO off ok
19:39:23 DEBUG| [stdout] not ok 49 selftests: net: veth.sh # exit=1

[Stefan Bader (smb)]

This seems to have been reported against the kernel as bug #1943697. Stated there is that it cannot be reproduced when running isolated and that it is no regression.

[Ian May (ian-may)]

Found on impish/linux-aws: 5.13.0-1008.9 a1.metal