Re: [PATCH net-next v2] selftests: net: replace sleeps in fcnal-test with waits

[David Ahern <dsahern@kernel.org>]

On 9/9/25 6:03 PM, Jakub Kicinski wrote:
> On Tue, 9 Sep 2025 16:59:28 -0600 David Ahern wrote:
>>> This makes some ping tests fail.
>>>
>>> https://netdev-3.bots.linux.dev/vmksft-net/results/289602/129-fcnal-other-sh/stdout
>>> https://netdev-3.bots.linux.dev/vmksft-net/results/289602/128-fcnal-ipv6-sh/stdout
>>>
>>> I only tested with debug kernels, but the non-debug get upset.
>>> I'll resend just the wait_local_port_listen changes. If the change
>>> gets more complex it's probably good to separate them out in the first
>>> place.  
>>
>> That is surprising to me. I will take look tomorrow.
> 
> Thanks! FWIW I repro'd one with "pause on fail" enabled and trying 
> to ping manually also wasn't working. Something odd.

This fixes it:

diff --git a/tools/testing/selftests/net/fcnal-test.sh
b/tools/testing/selftests/net/fcnal-test.sh
index 69941520e8e5..a527e3556763 100755
--- a/tools/testing/selftests/net/fcnal-test.sh
+++ b/tools/testing/selftests/net/fcnal-test.sh
@@ -189,7 +189,7 @@ show_hint()
 kill_procs()
 {
        killall nettest ping ping6 >/dev/null 2>&1
-       sleep 1
+       slowwait 2 sh -c 'test -z "$(pgrep '"'^(nettest|ping|ping6)$'"')"'
 }

 set_ping_group()
@@ -424,6 +424,8 @@ create_ns()
        ip netns exec ${ns} sysctl -qw net.ipv6.conf.all.keep_addr_on_down=1
        ip netns exec ${ns} sysctl -qw net.ipv6.conf.all.forwarding=1
        ip netns exec ${ns} sysctl -qw net.ipv6.conf.default.forwarding=1
+       ip netns exec ${ns} sysctl -qw net.ipv6.conf.default.accept_dad=0
+       ip netns exec ${ns} sysctl -qw net.ipv6.conf.all.accept_dad=0
 }

 # create veth pair to connect namespaces and apply addresses.