Re: [patch net-next v4 0/6] selftests: virtio_net: introduce initial testing infrastructure

["Michael S. Tsirkin" <mst@redhat.com>]

On Thu, Apr 18, 2024 at 06:08:24PM +0200, Jiri Pirko wrote:
> From: Jiri Pirko <jiri@nvidia.com>
> 
> This patchset aims at introducing very basic initial infrastructure
> for virtio_net testing, namely it focuses on virtio feature testing.
> 
> The first patch adds support for debugfs for virtio devices, allowing
> user to filter features to pretend to be driver that is not capable
> of the filtered feature.


virtio things:

Acked-by: Michael S. Tsirkin <mst@redhat.com>

> Example:
> $ cat /sys/bus/virtio/devices/virtio0/features
> 1110010111111111111101010000110010000000100000000000000000000000
> $ echo "5" >/sys/kernel/debug/virtio/virtio0/filter_feature_add
> $ cat /sys/kernel/debug/virtio/virtio0/filter_features
> 5
> $ echo "virtio0" > /sys/bus/virtio/drivers/virtio_net/unbind
> $ echo "virtio0" > /sys/bus/virtio/drivers/virtio_net/bind
> $ cat /sys/bus/virtio/devices/virtio0/features
> 1110000111111111111101010000110010000000100000000000000000000000
> 
> Leverage that in the last patch that lays ground for virtio_net
> selftests testing, including very basic F_MAC feature test.
> 
> To run this, do:
> $ make -C tools/testing/selftests/ TARGETS=drivers/net/virtio_net/ run_tests
> 
> It is assumed, as with lot of other selftests in the net group,
> that there are netdevices connected back-to-back. In this case,
> two virtio_net devices connected back to back. If you use "tap" qemu
> netdevice type, to configure this loop on a hypervisor, one may use
> this script:
> #!/bin/bash
> 
> DEV1="$1"
> DEV2="$2"
> 
> sudo tc qdisc add dev $DEV1 clsact
> sudo tc qdisc add dev $DEV2 clsact
> sudo tc filter add dev $DEV1 ingress protocol all pref 1 matchall action mirred egress redirect dev $DEV2
> sudo tc filter add dev $DEV2 ingress protocol all pref 1 matchall action mirred egress redirect dev $DEV1
> sudo ip link set $DEV1 up
> sudo ip link set $DEV2 up
> 
> Another possibility is to use virtme-ng like this:
> $ vng --network=loop
> or directly:
> $ vng --network=loop -- make -C tools/testing/selftests/ TARGETS=drivers/net/virtio_net/ run_tests
> 
> "loop" network type will take care of creating two "hubport" qemu netdevs
> putting them into a single hub.
> 
> To do it manually with qemu, pass following command line options:
> -nic hubport,hubid=1,id=nd0,model=virtio-net-pci
> -nic hubport,hubid=1,id=nd1,model=virtio-net-pci
> 
> ---
> v3->v4:
> - addressed comments from Petr and Benjamin, more or less cosmetical
>   issues. See individual patches changelog for details.
> - extended cover letter by vng usage
> v2->v3:
> - added forgotten kdoc entry in patch #1.
> v1->v2:
> - addressed comments from Jakub and Benjamin, see individual
>   patches #3, #5 and #6 for details.
> 
> Jiri Pirko (6):
>   virtio: add debugfs infrastructure to allow to debug virtio features
>   selftests: forwarding: move initial root check to the beginning
>   selftests: forwarding: add ability to assemble NETIFS array by driver
>     name
>   selftests: forwarding: add check_driver() helper
>   selftests: forwarding: add wait_for_dev() helper
>   selftests: virtio_net: add initial tests
> 
>  MAINTAINERS                                   |   1 +
>  drivers/virtio/Kconfig                        |   9 ++
>  drivers/virtio/Makefile                       |   1 +
>  drivers/virtio/virtio.c                       |   8 ++
>  drivers/virtio/virtio_debug.c                 | 109 +++++++++++++++
>  include/linux/virtio.h                        |  35 +++++
>  tools/testing/selftests/Makefile              |   1 +
>  .../selftests/drivers/net/virtio_net/Makefile |  15 ++
>  .../drivers/net/virtio_net/basic_features.sh  | 131 ++++++++++++++++++
>  .../selftests/drivers/net/virtio_net/config   |   2 +
>  .../net/virtio_net/virtio_net_common.sh       |  99 +++++++++++++
>  tools/testing/selftests/net/forwarding/lib.sh |  70 +++++++++-
>  12 files changed, 477 insertions(+), 4 deletions(-)
>  create mode 100644 drivers/virtio/virtio_debug.c
>  create mode 100644 tools/testing/selftests/drivers/net/virtio_net/Makefile
>  create mode 100755 tools/testing/selftests/drivers/net/virtio_net/basic_features.sh
>  create mode 100644 tools/testing/selftests/drivers/net/virtio_net/config
>  create mode 100644 tools/testing/selftests/drivers/net/virtio_net/virtio_net_common.sh
> 
> -- 
> 2.44.0