A Kernel Seedling

count is a file in /proc and any time we cat into count, proc_count is called

To count the number of processes, I used for_each_process to iterate through all the process in task_struct object and printed the result using seq_printf

Building

To build the module, I ran make If I made changes, I would first run make clean the make

Running

Loaded the module into the kernel using sudo insmod proc_count.ko Then ran the file through cat /proc/count, which called proc_count For me it produced the output of 139 follwed by a newline

Cleaning Up

To remove build artifcats, I called make clean Removed the module from kernel using sudo rmmod proc_count.ko

Testing

Before testing, I have to make Running python -m unittest produced ...

Ran tests in 16.658s

okay

Report which kernel release version you tested your module on (hint: use uname, check for options with man uname). It should match release numbers as seen on https://www.kernel.org/.

-r : kernel release -s: kernel name -v: kernel version

Running uname -r -s -v produced Linux 5.14.8-arch1-1 #1 SMP PREEMPT Sun, 26 Sep 2021 19:36:15 +0000