unregister_netdevice: waiting for C to become free. Usage count = 2
ref_tracker: netdev@ffffaf80198ae5e8 has 1/1 users at
     ref_tracker_alloc+0x1c4/0x542 lib/ref_tracker.c:277
     __netdev_tracker_alloc include/linux/netdevice.h:4346 [inline]
     netdev_tracker_alloc include/linux/netdevice.h:4358 [inline]
     netdev_get_by_index+0x7c/0xae net/core/dev.c:1008
     fib6_nh_init+0x790/0x1db6 net/ipv6/route.c:3592
     nh_create_ipv6 net/ipv4/nexthop.c:2862 [inline]
     nexthop_create net/ipv4/nexthop.c:2913 [inline]
     nexthop_add net/ipv4/nexthop.c:2950 [inline]
     rtm_new_nexthop+0x2298/0x8088 net/ipv4/nexthop.c:3264
     rtnetlink_rcv_msg+0x9e2/0xdbe net/core/rtnetlink.c:6946
     netlink_rcv_skb+0x206/0x3be net/netlink/af_netlink.c:2552
     rtnetlink_rcv+0x26/0x30 net/core/rtnetlink.c:6973
     netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
     netlink_unicast+0x544/0x88a net/netlink/af_netlink.c:1346
     netlink_sendmsg+0x860/0xdd8 net/netlink/af_netlink.c:1896
     sock_sendmsg_nosec net/socket.c:714 [inline]
     __sock_sendmsg+0xcc/0x160 net/socket.c:729
     ____sys_sendmsg+0x63e/0x79c net/socket.c:2614
     ___sys_sendmsg+0x144/0x1e6 net/socket.c:2668
     __sys_sendmsg+0x188/0x246 net/socket.c:2700
     __do_sys_sendmsg net/socket.c:2705 [inline]
     __se_sys_sendmsg net/socket.c:2703 [inline]
     __riscv_sys_sendmsg+0x70/0xa2 net/socket.c:2703
     syscall_handler+0x94/0x118 arch/riscv/include/asm/syscall.h:112
     do_trap_ecall_u+0x396/0x530 arch/riscv/kernel/traps.c:343