Sorry I replied privately. I am replying here again.
WIth the KNI, I have a listener listener as follows:
static void *kni_monitor_system_networking(void *data)
{
    struct mnl_socket *nl;
    char buf[MNL_SOCKET_BUFFER_SIZE];
    int ret;

    nl = mnl_socket_open(NETLINK_ROUTE);
    if (nl == NULL)
    {
        perror("mnl_socket_open");
        exit(EXIT_FAILURE);
    }

    if (mnl_socket_bind(nl, RTMGRP_LINK | RTMGRP_IPV4_IFADDR, MNL_SOCKET_AUTOPID) < 0)
    {
        perror("mnl_socket_bind");
        exit(EXIT_FAILURE);
    }

    ret = mnl_socket_recvfrom(nl, buf, sizeof(buf));
    while (ret > 0)
    {
        ret = mnl_cb_run(buf, ret, 0, 0, data_cb, NULL);
        if (ret <= 0)
            break;
        ret = mnl_socket_recvfrom(nl, buf, sizeof(buf));
    }
    if (ret == -1)
    {
        perror("error");
        exit(EXIT_FAILURE);
    }

    mnl_socket_close(nl);

    return 0;
}

But also I have a thread looping over rte_kni_handle_request:
while (1)
    {
        for (t = kni_tracker; t; t = t->next)
        {
            struct rte_kni *kni = (  struct rte_kni *  )t->kni;

            if (ppo->kni)
            {
                rte_kni_handle_request(kni);
        }

        usleep(10000);
    }

The rte_kni_handle_request calls the kni_config_promiscusity.
So from what you are saying, I can replace this call with another monitor on the netlink ports (the work will be on finding the correct flags and to implement the callback I guess)?
I from what I see,  mnl_socket_bind(nl, RTMGRP_LINK | RTMGRP_IPV4_IFADDR, MNL_SOCKET_AUTOPID) < 0) this linke should get also requests that are link related, but it doesn't seem to get any packets when I use tcpdump on the interface.