12.3. modprobe
Implemented as a BusyBox applet by default: https://git.busybox.net/busybox/tree/modutils/modprobe.c?h=1_29_stable
modprobe searches for modules installed under:
ls /lib/modules/<kernel_version>
and specified in the modules.order file.
This is the default install path for CONFIG_SOME_MOD=m modules built with make modules_install in the Linux kernel tree, with root path given by INSTALL_MOD_PATH, and therefore canonical in that sense.
Currently, there are only two kinds of kernel modules that you can try out with modprobe:
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modules built with Buildroot, see: Section 38.15.2.1, “kernel_modules buildroot package”
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modules built from the kernel tree itself, see: Section 17.11.2, “dummy-irq”
We are not installing out custom ./build-modules modules there, because:
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we don’t know the right way. Why is there no
installorinstall_modulestarget for kernel modules?This can of course be solved by running Buildroot in verbose mode, and copying whatever it is doing, initial exploration at: https://stackoverflow.com/questions/22783793/how-to-install-kernel-modules-from-source-code-error-while-make-process/53169078#53169078
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we would have to think how to not have to include the kernel modules twice in the root filesystem, but still have 9P working for fast development as described at: Section 2.2.2.2, “Your first kernel module hack”