Why kernel modules are useful?

Loadable kernel modules in an operating system is an object file that contains code to extend the running kernel, which is also known as the base kernel. The loadable kernel modules are used to add support for file systems, hardware, system calls etc.

What is the advantage of using modprobe over insmod to load a module into the kernel?

The modprobe command offers more features than the more basic insmod and rmmod utilities. modprobe intelligently adds or removes a module from the Linux kernel. Note that for convenience, there is no difference between _ and – in module names (automatic underscore conversion is performed).

What is the primary benefit of using kernel loadable modules?

Loadable kernel modules have several advantages over monolithic “blobs” of code in the kernel: * Device drivers don’t have to be hard-coded into the kernel. For example, if a new chip-set comes out that powers many webcams, that kernel module can simply be loaded instead of recompiling the kernel with the new module.

What is the effect of kernel macro __ exit if used when it unload the module from kernel?

The __exit macro causes the omission of the function when the module is built into the kernel, and like __exit, has no effect for loadable modules. Again, if you consider when the cleanup function runs, this makes complete sense; built-in drivers don’t need a cleanup function, while loadable modules do.

Is driver a kernel?

Device Drivers. A device driver is a loadable kernel module that manages data transfers between a device and the OS. Loadable modules are loaded at boot time or by request and are unloaded by request.

Why do kernel modules generally perform better than user space device drivers?

Kernel modules have higher execution privilege. Code that runs in kernel space has greater privilege than code that runs in user space. Driver modules potentially have a much greater impact on the system than user programs.

Why is modprobe preferred over using the insmod and Rmmod commands?

Most users will want to use modprobe instead, which is more clever and can handle module dependencies. modprobe: Much same way as insmod, but also loads any other modules that are required by the module that you want to load.

What are the two important characteristics of Linux loadable modules?

The Linux loadable modules have two important characteristics: Dynamic linking: A kernel module can be loaded and linked into the kernel while the kernel is already in memory and executing. A module can also be un- linked and removed from memory at any time. Stackable modules: The modules are arranged in a hierarchy.

Which system allows modules to tell the rest of the kernel that a new driver has become available?

driver registration
The driver registration allows modules to tell the rest of the kernel that a new driver has become available.