Linux Module Initialization Order
====== For static linked to Kernel case ======
Below is the initialization order from first to last. For details, refer to linux/init.h
  - core_initcall()
  - postcore_initcall()
  - arch_initcall()
  - subsys_initcall()
  - fs_initcall()
  - device_initcall()
  - late_initcall()

====== For dynamic loadable module ======
module_init(xxxx_init);
module_exit(xxxx_exit);