Re: [PATCH v2] selftests/net: enable lo.accept_local in psock_snd test

[Hangbin Liu <liuhangbin@gmail.com>]

On Wed, May 25, 2022 at 11:18:19AM +0800, Yun Lu wrote:
> From: luyun <luyun@kylinos.cn>
> 
> The psock_snd test sends and recieves packets over loopback, and
> the test results depend on parameter settings:
> Set rp_filter=0,
> or set rp_filter=1 and accept_local=1
> so that the test will pass. Otherwise, this test will fail with
> Resource temporarily unavailable:
> sudo ./psock_snd.sh
> dgram
> tx: 128
> rx: 142
> ./psock_snd: recv: Resource temporarily unavailable
> 
> For most distro kernel releases(like Ubuntu or Centos), the parameter
> rp_filter is enabled by default, so it's necessary to enable the
> parameter lo.accept_local in psock_snd test. And this test runs
> inside a netns, changing a sysctl is fine.
> 
> v2: add detailed description.
> 
> Suggested-by: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
> Signed-off-by: luyun <luyun@kylinos.cn>
> Reviewed-by: Jackie Liu <liuyun01@kylinos.cn>
> ---
>  tools/testing/selftests/net/psock_snd.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/tools/testing/selftests/net/psock_snd.c b/tools/testing/selftests/net/psock_snd.c
> index 7d15e10a9fb6..edf1e6f80d41 100644
> --- a/tools/testing/selftests/net/psock_snd.c
> +++ b/tools/testing/selftests/net/psock_snd.c
> @@ -389,6 +389,8 @@ int main(int argc, char **argv)
>  		error(1, errno, "ip link set mtu");
>  	if (system("ip addr add dev lo 172.17.0.1/24"))
>  		error(1, errno, "ip addr add");
> +	if (system("sysctl -w net.ipv4.conf.lo.accept_local=1"))
> +		error(1, errno, "sysctl lo.accept_local");
>  
>  	run_test();
>  
> -- 
> 2.25.1

Great, this also fixed my problem. Please feel free to add my

Tested-by: Hangbin Liu <liuhangbin@gmail.com>