On Tue, Sep 15, 2026 at 10:05 AM Xavier Simonart <[email protected]>
wrote:
> Hi Ales
>
> Thanks for the patch.
> Patch looks good to me.
> I am just wondering whether the "Fixes" tag is the most appropriate. It
> looks to me that the first part fixes 47203af82aba ("mac-cache: Send
> broadcast re-ARP probes after a while.")
> And the second part fixes 47203af82aba ("mac-cache: Send broadcast re-ARP
> probes after a while.").
>
> Other than that:
> Acked-by: Xavier Simonart <[email protected]>
>
> Thanks
> Xavier
>
>
> On Mon, Sep 14, 2026 at 3:34 PM Ales Musil via dev <
> [email protected]> wrote:
>
>> The probing tests used fixed delays and absolute probe counts around the
>> MAC binding aging deadline. Under load, controller statistics could
>> cross the deadline before a reply was processed, causing an active
>> binding to be removed.
>>
>> Synchronize with stale, used MAC cache flows while the binding still
>> exists, and compare probe counts relative to their observed values.
>> Reply to each neighbor as soon as its probe arrives so that serial
>> waits cannot consume the aging window.
>>
>> Fixes: 1e4fa9f174f1 ("mac-cache: Do not send probes for inactive MAC
>> Bindings.")
>> Assisted-by: GPT-5.6-sol, OpenCode
>> Signed-off-by: Ales Musil <[email protected]>
>> ---
>> tests/ovn.at | 47 ++++++++++++++++++++++++++++++-----------------
>> 1 file changed, 30 insertions(+), 17 deletions(-)
>>
>> diff --git a/tests/ovn.at b/tests/ovn.at
>> index 8acfecb7b..448e0818b 100644
>> --- a/tests/ovn.at
>> +++ b/tests/ovn.at
>> @@ -37738,14 +37738,12 @@ dump_arp 1 00:00:00:00:10:00 00:00:00:00:10:1b
>> 10.10.10.1 10.10.10.101 00:00:00:
>> dump_ns 00:00:00:00:10:1b 00:00:00:00:10:00 fd11::65 fd11::1 fd11::65 >
>> ucast_v6_65.pkt
>> OVS_WAIT_UNTIL([test $($PYTHON "$ovs_srcdir/utilities/ovs-pcap.in"
>> hv1/vif1-tx.pcap | \
>> grep -Fc "$(cat ucast_v4_101.pkt)") -ge 2])
>> +v4_ts=$(fetch_column Mac_Binding timestamp ip=10.10.10.101)
>> +send_garp hv1 vif1 2 00:00:00:00:10:1b 00:00:00:00:10:00 10.10.10.101
>> 10.10.10.1
>> +
>> OVS_WAIT_UNTIL([test $($PYTHON "$ovs_srcdir/utilities/ovs-pcap.in"
>> hv1/vif1-tx.pcap | \
>> grep -Fc "$(cat ucast_v6_65.pkt)") -ge 2])
>> -
>> -# The neighbours answer, refreshing the rows in place (resetting
>> -# arp_attempts). Confirm the timestamps advanced.
>> -v4_ts=$(fetch_column Mac_Binding timestamp ip=10.10.10.101)
>> v6_ts=$(fetch_column Mac_Binding timestamp ip=\"fd11::65\")
>> -send_garp hv1 vif1 2 00:00:00:00:10:1b 00:00:00:00:10:00 10.10.10.101
>> 10.10.10.1
>> send_na hv1 vif1 00:00:00:00:10:1b 00:00:00:00:10:00 fd11::65 fd11::1
>> OVS_WAIT_UNTIL([test $(fetch_column Mac_Binding timestamp
>> ip=10.10.10.101) -gt $v4_ts])
>> OVS_WAIT_UNTIL([test $(fetch_column Mac_Binding timestamp
>> ip=\"fd11::65\") -gt $v6_ts])
>> @@ -37869,6 +37867,25 @@ dump_icmp() {
>> echo $packet
>> }
>>
>> +mac_cache_flow_is_stale() {
>> + local flow=$1
>> + local stats field n_packets idle_age
>> +
>> + stats=$(as hv1 ovs-ofctl dump-flows br-int \
>> + "table=OFTABLE_MAC_CACHE_USE,$flow" | grep 'n_packets=')
>> + n_packets=
>> + idle_age=
>> + for field in $stats; do
>> + field=${field%,}
>> + case $field in
>> + n_packets=*) n_packets=${field#n_packets=} ;;
>> + idle_age=*) idle_age=${field#idle_age=} ;;
>> + esac
>> + done
>> +
>> + test "$n_packets" -gt 0 && test "$idle_age" -ge "$aging_th"
>> +}
>> +
>> aging_th=5
>> net_add n1
>> sim_add hv1
>> @@ -37928,17 +37945,15 @@ OVS_WAIT_UNTIL([$(ovs-ofctl dump-flows br-int
>> table=OFTABLE_MAC_BINDING | \
>>
>> send_icmp_echo_req hv1 public 00:00:00:00:10:00 00:00:00:00:10:1a
>> 192.168.20.2 192.168.10.100
>>
>> -# Wait until ovn-controller sends the ARP request.
>> -OVS_WAIT_UNTIL([test $(grep -c "Sending ARP/ND.*ip: 192.168.20.2"
>> hv1/ovn-controller.log) -eq 1])
>> -send_icmp_echo_req hv1 public 00:00:00:00:10:00 00:00:00:00:10:1a
>> 192.168.20.2 192.168.10.100
>> -
>> # Now drop ICMP echo reply in order to force OVN to arp the mac binding
>> entry
>> # for the distributed router lr.
>> check ovn-nbctl --wait=hv acl-add join from-lport 1000 'inport ==
>> "join-lr" && icmp' drop
>>
>> -sleep $((aging_th / 2))
>> +OVS_WAIT_UNTIL([mac_cache_flow_is_stale 'ip,nw_src=192.168.20.2'])
>> +
>> +probe_count=$(grep -c "Sending ARP/ND.*ip: 192.168.20.2"
>> hv1/ovn-controller.log)
>> send_icmp_echo_req hv1 public 00:00:00:00:10:00 00:00:00:00:10:1a
>> 192.168.20.2 192.168.10.100
>> -OVS_WAIT_UNTIL([test $(grep -c "Sending ARP/ND.*ip: 192.168.20.2"
>> hv1/ovn-controller.log) -eq 2])
>> +OVS_WAIT_UNTIL([test "$(grep -c "Sending ARP/ND.*ip: 192.168.20.2"
>> hv1/ovn-controller.log)" -gt "$probe_count"])
>>
>> check ovn-nbctl --wait=hv acl-del join
>> wait_row_count mac_binding 0 ip="192.168.10.100" logical_port="gw-public"
>> @@ -37949,17 +37964,15 @@ wait_row_count mac_binding 1
>> mac=\"00:00:00:00:30:00\" ip=\"fd12::2\"
>>
>> send_icmp6_echo_req hv1 public 00:00:00:00:10:00 00:00:00:00:50:01
>> fd12::2 fd11::64
>>
>> -# Wait until ovn-controller sends the NS request.
>> -OVS_WAIT_UNTIL([test $(grep -c "Sending ARP/ND.*ip: fd12::2"
>> hv1/ovn-controller.log) -eq 1])
>> -send_icmp6_echo_req hv1 public 00:00:00:00:10:00 00:00:00:00:50:01
>> fd12::2 fd11::64
>> -
>> # Now drop ICMPv6 echo reply in order to force OVN to send NS for the lr
>> mac binding entry.
>> check ovn-nbctl --wait=hv acl-add join from-lport 1010 'inport ==
>> "join-lr" && ip6 && icmp6.type == 0x87' allow
>> check ovn-nbctl --wait=hv acl-add join from-lport 1000 'inport ==
>> "join-lr" && icmp' drop
>>
>> -sleep $((aging_th / 2))
>> +OVS_WAIT_UNTIL([mac_cache_flow_is_stale 'ipv6,ipv6_src=fd12::2'])
>> +
>> +probe_count=$(grep -c "Sending ARP/ND.*ip: fd12::2"
>> hv1/ovn-controller.log)
>> send_icmp6_echo_req hv1 public 00:00:00:00:10:00 00:00:00:00:50:01
>> fd12::2 fd11::64
>> -OVS_WAIT_UNTIL([test $(grep -c "Sending ARP/ND.*ip: fd12::2"
>> hv1/ovn-controller.log) -eq 2])
>> +OVS_WAIT_UNTIL([test "$(grep -c "Sending ARP/ND.*ip: fd12::2"
>> hv1/ovn-controller.log)" -gt "$probe_count"])
>>
>> wait_row_count mac_binding 0 ip=\"fd12::2\" logical_port="gw-join"
>>
>> --
>> 2.55.0
>>
>> _______________________________________________
>> dev mailing list
>> [email protected]
>> https://mail.openvswitch.org/mailman/listinfo/ovs-dev
>>
>>
Thank you Xavier,
that's a fair point, I have also added the second Fixes tag. With that
applied to main and backported down to 25.09.
Regards,
Ales
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