From: Jack Min
> Currently PMD needs previous layer information in order to set
> corresponding match field for MPLSoGRE or MPLSoUDP.
>
> GRE_KEY item is missing as supported previous layer when translate item
> MPLS, which causes flow[1] cannot match MPLS over GRE traffic.
>
> According to RFC4023, MPLS over GRE tunnel with optional key field needs to
> be supported too.
>
> By adding missing GRE_KEY as supported previous layer fix problem.
>
> [1]:
> flow create 0 ingress pattern eth / ipv6 / gre k_bit is 1 / gre_key / mpls
> label is
> 966138 / end actions queue index 1 / mark id 0xa / end
>
> Fixes: a7a0365565a4 ("net/mlx5: match GRE key and present bits")
> Cc: sta...@dpdk.org
>
> Signed-off-by: Xiaoyu Min <jack...@nvidia.com>
Acked-by: Matan Azrad <ma...@nvidia.com>
