Subject: Re: [PATCH net] selftests: netfilter: nft_queue.sh: increase udp_gro_ct subtest timeout

From: Jakub Kicinski <[email-masked]>
Date: Tue, 24 Feb 2026 06:59:21 -0800

On Mon, 23 Feb 2026 20:00:58 +0100 Florian Westphal wrote:
> Jakub reports test flakes on debug kernels:
>  FAIL: test_udp_gro_ct: Expected software segmentation to occur, had 23 and 17
> 
> The nf_queue listener exits when it doesn't receive a new packet after
> 2s, seems this is too low. Use a 5 second timeout instead, same as the
> duration of the packet generation side.
> 
> Fixes: 59ecffa3995e ("selftests: netfilter: nft_queue.sh: add udp fraglist gro test case")
> Reported-by: Jakub Kicinski <[email-masked]>
> Closes: https://lore.kernel.org/netdev/[email-masked]/
> Signed-off-by: Florian Westphal <[email-masked]>
> ---
>  Hello, unfortunately I can't repro the flakes here, but 2s is rather
>  short and a nf_queue listener that exits while packets are still queued
>  does explain the error message (more packets counted as incoming than
>  outgoing).

Thanks for looking into it! Unfortunately we saw the problem again with
this patch applied:
https://netdev-ctrl.bots.linux.dev/logs/vmksft/nf-dbg/results/531881/3-nft-queue-sh/stdout

Looks like it repros once every 25 runs for us:
https://netdev.bots.linux.dev/contest.html?executor=vmksft-nf-dbg&test=nft-queue-sh