The Linux kernel is modular — composed of modules that work together but are largely independent of each other. New functionality can be added when a kernel module is loaded, but there are times when you might need to block functionality because modules interfere with each other or leave a system vulnerable. When that is the case, you can restrict what modules the kernel is able to use by blacklisting the troublemakers. This blocks them from being loaded.
Listing Kernel modules
You can list kernel modules with the lsmod command. For a taste of what you’re likely to see, the lsmod command below shows us the top of the lsmod command output on a sample system.
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