[ovs-git] [openvswitch/ovs] 696add: tc: handle packet mark of zero

[jahurley]

  Branch: refs/heads/branch-2.9
  Home:   https://github.com/openvswitch/ovs
  Commit: 696adde746596c3db9e1b0e09353762a1cf01b60
      https://github.com/openvswitch/ovs/commit/696adde746596c3db9e1b0e09353762a1cf01b60
  Author: John Hurley <john.hurley at netronome.com>
  Date:   2020-01-28 (Tue, 28 Jan 2020)

  Changed paths:
    M lib/netdev-tc-offloads.c

  Log Message:
  -----------
  tc: handle packet mark of zero

Openstack may set an skb mark of 0 in tunnel rules. This is considered to
be an unused/unset value. However, it prevents the rule from being
offloaded.

Check if the key value of the skb mark is 0 when it is in use (mask is
set to all ones). If it is then ignore the field and continue with TC offload.

Only the exact-match case is covered by this patch as it addresses the
Openstack use-case and seems most robust against feature evolution: f.e. in
future there may exist hardware offload scenarios where an operation, such
as a BPF offload, sets the SKB mark before proceeding tho the in-HW OVS.
datapath.

Signed-off-by: John Hurley <john.hurley at netronome.com>
Co-Authored-by: Simon Horman <simon.horman at netronome.com>
Signed-off-by: Simon Horman <simon.horman at netronome.com>
Acked-by: Aaron Conole <aconole at redhat.com>