From: Jiri Pirko <jiri@xxxxxxxxxx> 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. 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