Re: [PATCH net] selftests: net: bridge_vlan_mcast: wait for h1 before querier check

From: Sverdlin, Alexander

Date: Tue Apr 07 2026 - 05:03:43 EST


Hi Daniel,

On Sun, 2026-04-05 at 22:29 +0100, Daniel Golle wrote:
> The querier-interval test adds h1 (currently a slave of the VRF created
> by simple_if_init) to a temporary bridge br1 acting as an outside IGMP
> querier. The kernel VRF driver (drivers/net/vrf.c) calls cycle_netdev()
> on every slave add and remove, toggling the interface admin-down then up.
> Phylink takes the PHY down during the admin-down half of that cycle.
> Since h1 and swp1 are cable-connected, swp1 also loses its link may need
> several seconds to re-negotiate.
>
> Use setup_wait_dev $h1 0 which waits for h1 to return to UP state, so the
> test can rely on the link being back up at this point.
>
> Fixes: 4d8610ee8bd77 ("selftests: net: bridge: add vlan mcast_querier_interval tests")
> Signed-off-by: Daniel Golle <daniel@xxxxxxxxxxxxxx>

Reviewed-by: Alexander Sverdlin <alexander.sverdlin@xxxxxxxxxxx>

> ---
>  tools/testing/selftests/net/forwarding/bridge_vlan_mcast.sh | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/tools/testing/selftests/net/forwarding/bridge_vlan_mcast.sh b/tools/testing/selftests/net/forwarding/bridge_vlan_mcast.sh
> index 72dfbeaf56b92..e8031f68200ad 100755
> --- a/tools/testing/selftests/net/forwarding/bridge_vlan_mcast.sh
> +++ b/tools/testing/selftests/net/forwarding/bridge_vlan_mcast.sh
> @@ -414,6 +414,7 @@ vlmc_querier_intvl_test()
>   bridge vlan add vid 10 dev br1 self pvid untagged
>   ip link set dev $h1 master br1
>   ip link set dev br1 up
> + setup_wait_dev $h1 0
>   bridge vlan add vid 10 dev $h1 master
>   bridge vlan global set vid 10 dev br1 mcast_snooping 1 mcast_querier 1
>   sleep 2

--
Alexander Sverdlin
Siemens AG
www.siemens.com