Re: [PATCH net-next,v2] selftests: bonding: create directly devices in the target namespaces

[Hangbin Liu <liuhangbin@gmail.com>]

On Thu, Aug 24, 2023 at 09:57:15PM +0800, Zhengchao Shao wrote:
> If failed to set link1_1 to netns client, we should delete link1_1 in the
> cleanup path. But if set link1_1 to netns client successfully, delete
> link1_1 will report warning. So it will be safer creating directly the
> devices in the target namespaces.
> 
> Reported-by: Hangbin Liu <liuhangbin@gmail.com>
> Closes: https://lore.kernel.org/all/ZNyJx1HtXaUzOkNA@Laptop-X1/
> Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
> ---
> v2: create directly devices in the target namespaces
> ---
>  .../drivers/net/bonding/bond-arp-interval-causes-panic.sh | 8 +++-----
>  1 file changed, 3 insertions(+), 5 deletions(-)
> 
> diff --git a/tools/testing/selftests/drivers/net/bonding/bond-arp-interval-causes-panic.sh b/tools/testing/selftests/drivers/net/bonding/bond-arp-interval-causes-panic.sh
> index 7b2d421f09cf..fe7c34f89fc7 100755
> --- a/tools/testing/selftests/drivers/net/bonding/bond-arp-interval-causes-panic.sh
> +++ b/tools/testing/selftests/drivers/net/bonding/bond-arp-interval-causes-panic.sh
> @@ -22,14 +22,12 @@ server_ip4=192.168.1.254
>  echo 180 >/proc/sys/kernel/panic
>  
>  # build namespaces
> -ip link add dev link1_1 type veth peer name link1_2
> -
>  ip netns add "server"
> -ip link set dev link1_2 netns server up name eth0
> +ip netns add "client"
> +ip link add dev eth0 netns client type veth peer name eth0 netns server

When we already have an eth0 interface on init net, this cmd will failed

# ip link add dev eth0 netns client type veth peer name eth0 netns server
RTNETLINK answers: File exists

You should create the eth0 in the namespace, e.g.

# ip -n client link add eth0 type veth peer name eth0 netns server

Thanks
Hangbin