Re: [PATCH net-next v2 3/3] netdevsim: add selftest for forwarding skb between connected ports

[Jakub Kicinski <kuba@kernel.org>]

On Sat,  9 Dec 2023 17:04:48 -0800 David Wei wrote:
> From: David Wei <davidhwei@meta.com>
> 
> Connect two netdevsim ports in different namespaces together, then send
> packets between them using socat.
> 
> Signed-off-by: David Wei <dw@davidwei.uk>
> ---
>  .../selftests/drivers/net/netdevsim/peer.sh   | 111 ++++++++++++++++++
>  1 file changed, 111 insertions(+)
>  create mode 100755 tools/testing/selftests/drivers/net/netdevsim/peer.sh

You need to include this script in the Makefile so it gets run

> diff --git a/tools/testing/selftests/drivers/net/netdevsim/peer.sh b/tools/testing/selftests/drivers/net/netdevsim/peer.sh
> new file mode 100755
> index 000000000000..d1d59a932174
> --- /dev/null
> +++ b/tools/testing/selftests/drivers/net/netdevsim/peer.sh
> @@ -0,0 +1,111 @@
> +#!/bin/bash
> +# SPDX-License-Identifier: GPL-2.0-only
> +
> +NSIM_DEV_SYS=/sys/bus/netdevsim
> +NSIM_DEV_DFS=/sys/kernel/debug/netdevsim/netdevsim
> +
> +socat_check()
> +{
> +	if [ ! -x "$(command -v socat)" ]; then
> +		echo "socat command not found. Skipping test"
> +		return 1
> +	fi
> +
> +	return 0
> +}
> +
> +setup_ns()
> +{
> +	set -e
> +	ip netns add nssv
> +	ip netns add nscl
> +
> +	ip link set eni1np1 netns nssv
> +	ip link set eni2np1 netns nscl

This assumes you have systemd renaming interfaces.
I can find out what the netdev is called from sysfs.
After you create the nsim device in its sysfs dir
there will be a dir "net" and in it you'll have
a subdir with the same name as the netdev.

> +	ip netns exec nssv ip addr add '192.168.1.1/24' dev eni1np1
> +	ip netns exec nscl ip addr add '192.168.1.2/24' dev eni2np1
> +
> +	ip netns exec nssv ip link set dev eni1np1 up
> +	ip netns exec nscl ip link set dev eni2np1 up
> +	set +e
> +}
> +
> +cleanup_ns()
> +{
> +	ip netns del nscl
> +	ip netns del nssv
> +}
> +
> +###
> +### Code start
> +###
> +
> +modprobe netdevsim
> +
> +# linking
> +
> +echo 1 > ${NSIM_DEV_SYS}/new_device

Use $RANDOM to generate a random device ID.

> +echo "2 0" > ${NSIM_DEV_DFS}1/ports/0/peer 2>/dev/null
> +if [ $? -eq 0 ]; then
> +	echo "linking with non-existent netdevsim should fail"
> +	exit 1
> +fi
> +
> +echo 2 > /sys/bus/netdevsim/new_device
> +
> +echo "2 0" > ${NSIM_DEV_DFS}1/ports/0/peer
> +if [ $? -ne 0 ]; then
> +	echo "linking netdevsim1 port0 with netdevsim2 port0 should succeed"
> +	exit 1
> +fi
> +
> +# argument error checking
> +
> +echo "2 1" > ${NSIM_DEV_DFS}1/ports/0/peer 2>/dev/null
> +if [ $? -eq 0 ]; then
> +	echo "linking with non-existent port in a netdevsim should fail"
> +	exit 1
> +fi
> +
> +echo "1 0" > ${NSIM_DEV_DFS}1/ports/0/peer 2>/dev/null
> +if [ $? -eq 0 ]; then
> +	echo "linking with self should fail"
> +	exit 1
> +fi
> +
> +echo "2 a" > ${NSIM_DEV_DFS}1/ports/0/peer 2>/dev/null
> +if [ $? -eq 0 ]; then
> +	echo "invalid arg should fail"
> +	exit 1
> +fi
> +
> +# send/recv packets
> +
> +socat_check || exit 1

There's a magic return value for skipping kselftests, 1 means fail.
-- 
pw-bot: cr