How to produce: same step as bug(https://dpdk.org/tracker/show_bug.cgi?id=14) kernel log: Feb 06 19:01:40 yf-mos-test-net20 kernel: Detected Tx Unit Hang Tx Queue <0> TDH, TDT <0>, <6> next_to_use <6> next_to_clean <0> tx_buffer_info[next_to_clean] next_to_watch <ffff8801a070c010> eop_desc->wb.status <128280> time_stamp <13079e940> jiffies <13079ee06> Feb 06 19:01:40 yf-mos-test-net20 ovs-vswitchdm[13237]: PMD: VF 0: disabling multicast promiscuous