Hi! The purpose of this series is to add a software model of BPF offloads to make it easier for everyone to test them and make some of the more arcane rules and assumptions more clear.
The series starts with 3 patches aiming to make XDP handling in the drivers less error prone. Currently driver authors have to remember to free XDP programs if XDP is active during unregister. With this series the core will disable XDP on its own. It will take place after close, drivers are not expected to perform reconfiguration when disabling XDP on a downed device. Next two patches add the software netdev driver. Last but not least there is a python test which exercises all the corner cases which came to my mind. Test needs to be run as root. It will print basic information to stdout, but can also create a more detailed log of all commands when --log option is passed. Log is in Emacs Org-mode format. ./tools/testing/selftests/bpf/test_offload.py --log /tmp/log Something I'm still battling with, and would appreciate help of wiser people is that occasionally during the test something makes the refcount of init_net drop to 0 :S I tried to create a simple reproducer, but seems like just running the script in the loop is the easiest way to go... Could it have something to do with the recent TC work? The driver is pretty simple and never touches ref counts. The only slightly unusual thing is that the BPF code sleeps for a bit on remove in the netdev notifier. Jakub Kicinski (6): net: xdp: avoid output parameters when querying XDP prog net: xdp: report flags program was installed with on query net: xdp: make the stack take care of the tear down netdevsim: add software driver for testing offloads netdevsim: add bpf offload support selftests/bpf: add offload test based on netdevsim MAINTAINERS | 5 + drivers/net/Kconfig | 10 + drivers/net/Makefile | 1 + drivers/net/ethernet/broadcom/bnxt/bnxt.c | 2 - drivers/net/ethernet/mellanox/mlx5/core/en_main.c | 3 - drivers/net/ethernet/netronome/nfp/bpf/main.c | 7 - .../net/ethernet/netronome/nfp/nfp_net_common.c | 4 +- drivers/net/ethernet/qlogic/qede/qede_main.c | 4 - drivers/net/netdevsim/Makefile | 7 + drivers/net/netdevsim/bpf.c | 391 +++++++++++++ drivers/net/netdevsim/netdev.c | 241 ++++++++ drivers/net/netdevsim/netdevsim.h | 84 +++ drivers/net/tun.c | 4 - include/linux/netdevice.h | 5 +- net/core/dev.c | 42 +- net/core/rtnetlink.c | 6 +- tools/testing/selftests/bpf/Makefile | 5 +- tools/testing/selftests/bpf/sample_ret0.c | 8 + tools/testing/selftests/bpf/test_offload.py | 634 +++++++++++++++++++++ 19 files changed, 1426 insertions(+), 37 deletions(-) create mode 100644 drivers/net/netdevsim/Makefile create mode 100644 drivers/net/netdevsim/bpf.c create mode 100644 drivers/net/netdevsim/netdev.c create mode 100644 drivers/net/netdevsim/netdevsim.h create mode 100644 tools/testing/selftests/bpf/sample_ret0.c create mode 100755 tools/testing/selftests/bpf/test_offload.py -- 2.14.1
