Hello Ansen An,
This feature is not available on the i.MX BSP. However, you should be able to look for information about the Linux livepatch feature that I think satisfies your requirement. This feature allows to update the kernel without the need for reboot. You can find more information here:
https://www.kernel.org/doc/Documentation/livepatch/livepatch.txt
I hope this helps!
Regards,