Root Cause:

    There are two i40evf drivers, one is in dpdk the other is kernel built-in, 

    the crash occurs when built-in i40evf driver unbind NIC.
Solution:

    Using a workaround solution, as we only need the DPDK i40evf driver, 

    add the kernel's built-in driver to blacklist to prevent kernel panic.

Before:

[root@AN test]# lsmod | grep i40evf

i40evf                53833  0
After:

[root@AN test]# lsmod | grep i40evf