x86,aarch64,arm

Ciro Santilli c4b4f029d4 cannot insmoe workqueue: module already loaded, even though lsmod says otherwise		8 years ago
buildroot @ 083c0735e9	338756a029 bak	8 years ago
host	8eb878c24e update	8 years ago
kernel_module	c4b4f029d4 cannot insmoe workqueue: module already loaded, even though lsmod says otherwise	8 years ago
rootfs_overlay	8d20f8ce30 llseek	8 years ago
.gitignore	d45ceace5d 0	8 years ago
.gitmodules	338756a029 bak	8 years ago
README.md	67f669487e Workqueue attempt, but fails to insmod, already loaded??	8 years ago
bibliography.md	bf3bb0cb18 fops read returns some data, busybox config frag for stat, bibliography start	8 years ago
build.md	8eb878c24e update	8 years ago
busybox_config_fragment	bf3bb0cb18 fops read returns some data, busybox config frag for stat, bibliography start	8 years ago
introduction.md	d45ceace5d 0	8 years ago
kernel_config_fragment	0279ae3bad Better name for config fragment	8 years ago
kmod.md	d45ceace5d 0	8 years ago
run	bf3bb0cb18 fops read returns some data, busybox config frag for stat, bibliography start	8 years ago

Linux Kernel Module Cheat

Run one command, get into QEMU Buildroot BusyBox with several minimal Linux kernel module example tutorials. Tested in Ubuntu 14.04.

Usage:

./run

First build will take a while (GCC, Linux kernel).

QEMU opens up, and you can run:

insmod /hello.ko
insmod /hello2.ko
rmmod hello
rmmod hello2

Each module comes from a C file under kernel_module/. head *.c for module usage.

The Linux kernel version can be found with:

grep BR2_LINUX_KERNEL_VERSION buildroot/.config

We use printk a lot, and it shows on the QEMU terminal by default. If that annoys you (e.g. you want to see stdout separately), do:

dmesg -n 1