Hello,

I try to use af_xdp of DPDK 19.11, but start failed with testpmd. Here is the log prints, could you please give suggestion for this error ? Thanks in advance!

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[root@gc bin]$ ./testpmd -l 1,2,3 -n 4 --log-level=pmd.net.af_xdp:info --no-pci --vdev net_af_xdp,iface=ens12,start_queue=0,queue_count=3 -- -i --rxq=3 --txq=3
EAL: Detected 16 lcore(s)
EAL: Detected 1 NUMA nodes
EAL: Multi-process socket /var/run/dpdk/rte/mp_socket
EAL: Selected IOVA mode 'PA'
EAL: No available hugepages reported in hugepages-1048576kB
EAL: Probing VFIO support...
rte_pmd_af_xdp_probe(): Initializing pmd_af_xdp for net_af_xdp
init_internals(): Zero copy between umem and mbuf enabled.
Interactive-mode selected
testpmd: create a new mbuf pool <mbuf_pool_socket_0>: n=163456, size=2176, socket=0
testpmd: preferred mempool ops selected: ring_mp_mc

Warning! port-topology=paired and odd forward ports number, the last port will pair with itself.

Configuring Port 0 (socket 0)
eth_rx_queue_setup(): Set up rx queue, rx queue id: 0, xsk queue id: 0
libbpf: can't get next link: Invalid argument
eth_rx_queue_setup(): Set up rx queue, rx queue id: 1, xsk queue id: 1
libbpf: can't get next link: Invalid argument
eth_rx_queue_setup(): Set up rx queue, rx queue id: 2, xsk queue id: 2
libbpf: can't get next link: Invalid argument
Port 0: FA:0C:B1:0F:DF:01
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My test env:
DPDK: stable 19.11.6
libbpf: git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git
OS£ºCentos 7.9 + kernel 5.4.155-1.el7.elrepo.x86_64


Br,
Christian