Re: [PATCH net v2 6/6] selftests: drv-net: Add VLAN test

On Fri, Aug 21, 2026 at 05:09:59PM +0000, Ovidiu Panait wrote:

Add a test that validates ping traffic over VLAN interfaces. It aims
to catch drivers which mishandle hardware VLAN tag stripping, in
particular QinQ.

Three VLAN configurations are covered, each with hardware VLAN stripping
enabled and disabled:
- a single 802.1q VLAN interface
- a single 802.1ad VLAN interface
- an 802.1q VLAN stacked on top of an 802.1ad interface

NETIF=end1 LOCAL_V4=172.16.0.2 REMOTE_V4=172.16.0.3 \
REMOTE_TYPE=ssh REMOTE_ARGS=root@172.16.0.3 \
run_kselftest.sh -t drivers/net:vlan.py
  TAP version 13
  1..1
  # timeout set to 360
  # selftests: drivers/net: vlan.py
  # # Interface: end0, driver: st_gmac
  # TAP version 13
  # 1..6
  # ok 1 vlan.test.8021q_hw
  # ok 2 vlan.test.8021q_sw
  # ok 3 vlan.test.8021ad_hw
  # ok 4 vlan.test.8021ad_sw
  # ok 5 vlan.test.qinq_hw
  # ok 6 vlan.test.qinq_sw
  # # Totals: pass:6 fail:0 xfail:0 xpass:0 skip:0 error:0

+def _setup(cfg, outer_proto, inner_proto, hw_strip):
+    """Configure VLAN stripping and create the VLAN interfaces."""
+
+    feat = ethtool(f"-k {cfg.ifname}", json=True)[0]
+    set_ethtool_feat(cfg.ifname, feat, {"rx-vlan-offload": hw_strip})

+        if current[name]["active"] != state:
+            no_change = False
+            if current[name]["fixed"]:
+                raise KsftXfailEx(f"Device does not support {name}")

I'm not too familiar with the self test framework, so i could have
this wrong.

It looks to me like you fail the text if it is fixed. But does not
fixed just mean the hardware does not support it? So i think it should
actually skip the test?

Now, if it does not say fixed, but ethtool -K reports EOPNOTSUPP, that
would be an error.

Having said that, thanks for spending the time to add a test. We need
more tests like this.

     Andrew