Linux Kernel Module Cheat

38.15.2. buildroot_packages directory

Every directory inside it is a Buildroot package.

Those packages get automatically added to Buildroot’s BR2_EXTERNAL, so all you need to do is to turn them on during build, e.g.:

./build-buildroot --config 'BR2_PACKAGE_SAMPLE_PACKAGE=y'

then test it out with:

./run --eval-after '/sample_package.out'

and you should see:

hello sample_package

Source: buildroot_packages/sample_package/sample_package.c

You can force a rebuild with:

./build-buildroot --config 'BR2_PACKAGE_SAMPLE_PACKAGE=y' -- sample_package-reconfigure

Buildroot packages are convenient, but in general, if a package if very important to you, but not really mergeable back to Buildroot, you might want to just use a custom build script for it, and point it to the Buildroot toolchain, and then use BR2_ROOTFS_OVERLAY, much like we do for Userland setup.

A custom build script can give you more flexibility: e.g. the package can be made work with other root filesystems more easily, have better 9P support, and rebuild faster as it evades some Buildroot boilerplate.

kernel_modules buildroot package