Modules and kernel version

• To be compiled, a kernel module needs access to the kernel headers, containing the functions, types and constants definitions

• Two solutions

• Full kernel sources
• Only kernel headers (linux-headers-* packages in Debian/Ubuntu distributions)

• The sources or headers must be configured

• Many macros or functions depend on the configuration

• A kernel module compiled against version X of kernel headers will not load in kernel version Y

• modprobe/insmod will say « Invalid module format »