Re: [PATCH net] selftests: net: fix race condition in icmp.sh causing CKI sporadic failures

[Jakub Kicinski <kuba@kernel.org>]

On Mon, 12 Oct 2026 18:23:32 +0530 Prasenjit Mukherjee wrote:
> CKI reports sporadic failures in icmp.sh, Davide suggests this might be

Please expand local acronyms, no idea what CKI was, I had to google it.

> caused by a race condition where tcpdump starts capturing after the last of
> expected ICMP unreachable packets have been sent.
> Fix this replacing tcpdump with a tc flower filter that
> matches ICMP Destination Unreachable (type 3, code 0),
> and match on act_gact counters instead.
> This will remove any race condition to appear.

Would really be great if you could say something like "with this patch
applied I run the test in $my-ci and no failures happened"

> Fixes: 7e9838b7915e2 ("selftests/net: Add icmp.sh for testing ICMP dummy address responses")
> CC: Toke Høiland-Jørgensen <toke@redhat.com>
> Suggested-by: Davide Caratti <dcaratti@redhat.com>
> Reviewed-by: Davide Caratti <dcaratti@redhat.com>
> Reported-by: CKI Project <cki-project@redhat.com>
> Closes: https://datawarehouse.cki-project.org/issue/3658

Silly number of tags