I am trying to create an RTE flow rule to match head and non-head fragments to
compute NIC RSS based on 5tuple/3tuple respectively on connectX-6 DX NIC and
mlx5 driver. 

As part of it when trying to install RTE flow rule using testpmd on dpdk
21.11/23.07 version, the following errors are thrown.

Flow rule to match head fragment
=================================
testpmd>  flow create 0 ingress pattern eth / ipv4 fragment_offset spec 0x2000
fragment_offset mask 0x3fff / end actions drop / count / end
port_flow_complain(): Caught PMD error type 13 (specific pattern item): cause:
0x7ffd1954c548, match on first fragment not supported: Operation not supported

Flow rule to match non-head fragments
======================================
testpmd> flow validate 0 ingress pattern eth / ipv4 fragment_offset is 0x2001
fragment_offset last 0x1fff / end actions drop / end
port_flow_complain(): Caught PMD error type 11 (item specification range):
cause: 0x7ffc6f629534, specified range not supported: Operation not supported

When I browsed mlx5_flow_dv.c driver file, there are set of conditions
implemented to block this configurations.

Could you kindly help is there a way to compute different RSS hash for
fragments and non-fragments using RTE flow rules on mellanox?

Thanks! in advance.

       /*
         * Match on fragment_offset 0x2000 means MF is 1 and frag-offset is 0,
         * indicating this is 1st fragment of fragmented packet.
         * This is not yet supported in MLX5, return appropriate error message.
         */
        if (fragment_offset_spec == RTE_BE16(RTE_IPV4_HDR_MF_FLAG))
                return rte_flow_error_set(error, ENOTSUP,
                                          RTE_FLOW_ERROR_TYPE_ITEM, item,
                                          "match on first fragment not "
                                          "supported");
        if (fragment_offset_spec && !last)
                return rte_flow_error_set(error, ENOTSUP,
                                          RTE_FLOW_ERROR_TYPE_ITEM, item,
                                          "specified value not supported");
        /*
         * Match on fragment_offset spec 0x2001 and last 0x3fff
         * means MF is 1 and frag-offset is > 0.
         * This packet is fragment 2nd and onward, excluding last.
         * This is not yet supported in MLX5, return appropriate
         * error message.
         */
        if (fragment_offset_spec == RTE_BE16(RTE_IPV4_HDR_MF_FLAG + 1) &&
            fragment_offset_last == RTE_BE16(MLX5_IPV4_FRAG_OFFSET_MASK))
                return rte_flow_error_set(error, ENOTSUP,
                                          RTE_FLOW_ERROR_TYPE_ITEM_LAST,
                                          last, "match on following "
                                          "fragments not supported");
        /*
         * Match on fragment_offset spec 0x0001 and last 0x1fff
         * means MF is 0 and frag-offset is > 0.
         * This packet is last fragment of fragmented packet.
         * This is not yet supported in MLX5, return appropriate
         * error message.
         */
        if (fragment_offset_spec == RTE_BE16(1) &&
            fragment_offset_last == RTE_BE16(RTE_IPV4_HDR_OFFSET_MASK))
                return rte_flow_error_set(error, ENOTSUP,
                                          RTE_FLOW_ERROR_TYPE_ITEM_LAST,
                                          last, "match on last "
                                          "fragment not supported");