Hi there,

I'm trying to distribute among the Rx queues flows of TCP packets based on their destination IPv4 address and source TCP port. I'm using the rte_flow DPDK API for this purpose. I'm using DPDK 20.11.0. The setup is successful when the application is started on a server with i40e driver but fails when the application is started on a server using igb driver.

In the failure case the validation function returns EINVAL and the error message is "only two tuple are supported by this filter".
I checked the source code of this DPDK driver in drivers/net/e1000/igb_flow.c and I saw the following related code there, starting at line 449:

        if (filter->src_ip_mask || filter->dst_ip_mask ||                      
            filter->src_port_mask) {                                            
            memset(filter, 0, sizeof(struct rte_eth_ntuple_filter));            
            rte_flow_error_set(error, EINVAL,                                  
                RTE_FLOW_ERROR_TYPE_ITEM,                                      
                NULL, "only two tuple are "                                    
                "supported by this filter");                                    
            return -rte_errno;                                                  
        }

The condition looks odd to me because it seems to ensure that only filtering by destination port is supported while the error message hints for something else. Why would filtering only by the destination port be allowed!?
I've provided dst_ip_mask = 0xFFFFFFFF and src_port_mask 0xFFFF because I just want to match exact ips and ports and in my understanding this should classify, in my understanding, as filtering by "two tuple" - destination ip and source port.

So, my questions are:

1. Am I missing something about this condition and thus it's the way it should be?

2. If the question is not appropriate for this user group where should I post it - dev@dpdk.org?