[PATCH bpf] selftests: xsk: Disable IPv6 on VETH1

[PATCH bpf] selftests: xsk: Disable IPv6 on VETH1

[Kal Conley]

This change fixes flakiness in the BIDIRECTIONAL test:

    # [is_pkt_valid] expected length [60], got length [90]
    not ok 1 FAIL: SKB BUSY-POLL BIDIRECTIONAL

When IPv6 is enabled, the interface will periodically send MLDv1 and
MLDv2 packets. These packets can cause the BIDIRECTIONAL test to fail
since it uses VETH0 for RX.

For other tests, this was not a problem since they only receive on VETH1
and IPv6 was already disabled on VETH0.

Fixes: a89052572ebb ("selftests/bpf: Xsk selftests framework")
Signed-off-by: Kal Conley <kal.conley@dectris.com>
---
 tools/testing/selftests/bpf/test_xsk.sh | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tools/testing/selftests/bpf/test_xsk.sh b/tools/testing/selftests/bpf/test_xsk.sh
index b077cf58f825..377fb157a57c 100755
--- a/tools/testing/selftests/bpf/test_xsk.sh
+++ b/tools/testing/selftests/bpf/test_xsk.sh
@@ -116,6 +116,7 @@ setup_vethPairs() {
 	ip link add ${VETH0} numtxqueues 4 numrxqueues 4 type veth peer name ${VETH1} numtxqueues 4 numrxqueues 4
 	if [ -f /proc/net/if_inet6 ]; then
 		echo 1 > /proc/sys/net/ipv6/conf/${VETH0}/disable_ipv6
+		echo 1 > /proc/sys/net/ipv6/conf/${VETH1}/disable_ipv6
 	fi
 	if [[ $verbose -eq 1 ]]; then
 	        echo "setting up ${VETH1}"
-- 
2.39.2

Re: [PATCH bpf] selftests: xsk: Disable IPv6 on VETH1

[Andrii Nakryiko]

On Mon, Apr 3, 2023 at 5:05 AM Kal Conley <kal.conley@dectris.com> wrote:
>
> This change fixes flakiness in the BIDIRECTIONAL test:
>
>     # [is_pkt_valid] expected length [60], got length [90]
>     not ok 1 FAIL: SKB BUSY-POLL BIDIRECTIONAL
>
> When IPv6 is enabled, the interface will periodically send MLDv1 and
> MLDv2 packets. These packets can cause the BIDIRECTIONAL test to fail
> since it uses VETH0 for RX.
>
> For other tests, this was not a problem since they only receive on VETH1
> and IPv6 was already disabled on VETH0.
>
> Fixes: a89052572ebb ("selftests/bpf: Xsk selftests framework")
> Signed-off-by: Kal Conley <kal.conley@dectris.com>
> ---

Can you please resubmit with [PATCH bpf-next] tag, so BPF CI can test
it against the bpf-next tree. Thanks.

>  tools/testing/selftests/bpf/test_xsk.sh | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/tools/testing/selftests/bpf/test_xsk.sh b/tools/testing/selftests/bpf/test_xsk.sh
> index b077cf58f825..377fb157a57c 100755
> --- a/tools/testing/selftests/bpf/test_xsk.sh
> +++ b/tools/testing/selftests/bpf/test_xsk.sh
> @@ -116,6 +116,7 @@ setup_vethPairs() {
>         ip link add ${VETH0} numtxqueues 4 numrxqueues 4 type veth peer name ${VETH1} numtxqueues 4 numrxqueues 4
>         if [ -f /proc/net/if_inet6 ]; then
>                 echo 1 > /proc/sys/net/ipv6/conf/${VETH0}/disable_ipv6
> +               echo 1 > /proc/sys/net/ipv6/conf/${VETH1}/disable_ipv6
>         fi
>         if [[ $verbose -eq 1 ]]; then
>                 echo "setting up ${VETH1}"
> --
> 2.39.2
>