ADQ VF Issues

• When ADQ is enabled on VFs, TC filters on the VF TC0 (default TC) are not supported and do not pass traffic. It is not expected to add TC filters to TC0 since it is reserved for non-filtered default traffic.
• When TC offload is disabled on a VF interface, the iavf driver allows ADQ configuration steps to add TCs and TC filters to the VF interface. Expected behavior is for the iavf driver to return an error message if hw-tc-offload is set to off.

  Mitigation: Enable the hw-tc-offload flag on the VF interface:

  ethtool -K $vf_iface hw-tc-offload on
• When ADQ is enabled on a VF interface, the tc qdisc add command causes the VF connection (ping) to drop when using ice-1.8.x and iavf-4.4.x

  Mitigation: Use previous versions of the ice and iavf drivers for ADQ VF (ice-1.7.16 with iavf-4.3.19).

  .
• Configuring ADQ traffic classes with an odd number of HW queues on a VF interface might result in system hang in the iavf driver.

  Mitigation: Configure even number of queues in the tc qdisc add dev command.

• TC VF filters do not correctly handle ADQ filter queues, causing ADQ SR-IOV application traffic to be directed to hardware queue(s) in the default traffic class (TC0).

  Mitigation: Use ice driver version 1.6.4 or later.