(In the Linux 2.4 kernel, the compilation of modules only requires the kernel source dock file, and the MODULES is defined before the Linux/modules. h header file is included, and the suffix of the kernel modules generated after the compilation and connection is. o. In the 2.6 kernel, the compilation requirements of modules depend on the configured kernel source code. The compilation process will first go to the kernel source code object to read the top-level Makefile file, and the suffix of the kernel module generated after compilation and connection is. ko)