[Verse 1] Deep beneath the applications that we see each day Lives a kernel space so different from the user's way No malloc here, no printf calls to help you debug Just kernel memory and printk when your code gets stuck [Chorus] Init and exit, that's the way Module load and cleanup, every day Register your driver, claim your space Kernel module dancing in the system's embrace From user land to kernel land Understanding where you stand [Verse 2] Start with hashtag include, bring the headers that you need Linux slash module dot h, that's the kernel's creed Module underscore init marks your entry function clear Module underscore exit when it's time to disappear [Chorus] Init and exit, that's the way Module load and cleanup, every day Register your driver, claim your space Kernel module dancing in the system's embrace From user land to kernel land Understanding where you stand [Verse 3] No floating point allowed, interrupts can steal your time GFP underscore KERNEL when you need memory sublime Return zero for success, negative for error state Static functions keep it clean, don't pollute the kernel's gate [Bridge] Makefile magic, obj dash m Point to kernel build and then Make will compile your C code Insert mod to load your node [Chorus] Init and exit, that's the way Module load and cleanup, every day Register your driver, claim your space Kernel module dancing in the system's embrace From user land to kernel land Understanding where you stand [Verse 4] Register your device node, claim your major number slot Character or block device, choose the type that fits your plot File operations structure holds your read and write and more Open, close, and ioctl knocking at your driver's door [Outro] Hello kernel, goodbye user space Welcome to the driver's place Module loaded, system knows That's how kernel programming goes
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