[dpdk-stable] [dpdk-dev] net/mlx5: mellanox cx5/cx6-dx increment "rx_phy_discard_packets" with DPDK rte_flow actions COUNT & DROP

[Arthas]

Hareware:  CX5/CX6 DX + Intel(R) Xeon(R) Platinum 9242 CPU @ 2.30GHz  DPDK version: 19.11.8/20.11/21.05-rc1&2


testpmd with case:
testpmd> flow create 0 ingress pattern eth / ipv4 / udp dst is 53 / end actions count / drop / end
testpmd> flow create 0 ingress pattern eth / ipv4 / udp src is 53 / end actions count / drop / end
testpmd> flow create 0 ingress pattern eth / ipv4 / tcp / end actions count /drop end

testpmd> flow list 0
ID	Group	Prio	Attr	Rule
0	0	0	i--	ETH IPV4 UDP => COUNT DROP
1	0	0	i--	ETH IPV4 UDP => COUNT DROP
2	0	0	i--	ETH IPV4 UDP => COUNT DROP

or
testpmd> flow create 0 ingress pattern eth / ipv4 / udp dst is 53 / end actions count / rss / end
testpmd> flow create 0 ingress pattern eth / ipv4 / udp src is 53 / end actions count / rss / end
testpmd> flow create 0 ingress pattern eth / ipv4 / udp / end actions count / rss / end
testpmd> flow list 0
ID	Group	Prio	Attr	Rule
0	0	0	i--	ETH IPV4 UDP => COUNT RSS
1	0	0	i--	ETH IPV4 UDP => COUNT RSS
2	0	0	i--	ETH IPV4 UDP => COUNT RSS
testpmd> 



as soon as NIC create more than 1 flow ,  CX5/CX6-dx NIC will increment 'rx_phy_discard_packets'.
only 1 flow no problem!


Is this a CX5/CX6-DX hardware issue? 
or Is it a DPDK mlx5 pmd bugs?


Best Regards!
KANG