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Highlights from Linux Kernel Mentorship Program 2024 by Abdul Rahim
My journey with Linux Kernel Development
Introduction
Linux is the kernel that powers the modern computing world. It’s everywhere—from all the top 500 supercomputers running Linux, to over two-thirds of mobile phones using it, and more than 95% of servers relying on it. Impressive, right? But this blog isn’t about why Linux dominates the tech world; it’s about how I started contributing to the Linux Kernel—and how you can too.
How Kernel Development Works
Kernel development thrives on the Linux Kernel Mailing List (LKML), the
nerve center of Linux’s open-source ecosystem. The beauty of open
source? Anyone can contribute. Your task is to send patches (essentially
the output of git diff refurbushed into an email).
If your patch solves a real problem or adds value, experienced developers will jump in with questions about your intent and rationale. Here’s a pro tip: don’t explain the how of your code; let the code speak for itself. Instead, focus on explaining why your change is needed.
The LKML community is incredibly supportive – they’ll critique your code, point out mistakes, and suggest improvements. Sure, it might feel overwhelming initially, but resources like the LFD103 course can guide you through the basics: generating patches, submitting them to LKML, compiling, and booting the kernel.
For me, just setting up my mail client and understanding LKML discussions took about a month. But once you clear these initial hurdles, things get easier. If you’re struggling, feel free to check out my notes—they might save you some time.
My Background
For years, kernel developers seemed like magicians to me—doing impossibly cool things with computers. My fascination started after I stumbled upon a video of someone working on the kernel. It was mesmerizing!
In my second semester, I discovered the book The C Programming Language, and it sparked my love for C. The control C offers is unmatched, but it comes with its fair share of challenges—bugs galore!
Surprisingly, I wasn’t a Linux user until recently. When I finally switched from Windows to Linux, everything just clicked. Concepts that once felt abstract suddenly made sense. On Windows, troubleshooting often felt like solving a mystery even Microsoft couldn’t decode. On Linux, it felt like someone handed me the keys to the entire system.
While working on kernel contributions, I read Linux Device Drivers, a book authored by seasoned kernel developers. It gave me a deeper understanding of the kernel’s inner workings. If you’re serious about kernel development or writing drivers, this book is a must-read.
What to Contribute
The hardest part of contributing to the Linux Kernel is figuring out what to work on. The kernel is vast—there’s everything from GPU drivers to network stack development.
Since the kernel’s primary job is managing hardware, driver development is a hotspot of activity. New devices constantly hit the market, and they need drivers. If you have an electronics background and access to hardware, driver development is an excellent starting point.
If hardware isn’t your thing (like in my case), here are some alternatives:
- kselftest: A testing framework for kernel functionality.
- Core subsystems: The backbone of the kernel—a great way to learn the essentials.
- syzbot reports: A kernel fuzzer that uncovers bugs by feeding the kernel random data. These reports are a goldmine for learning about common mistakes.
Another beginner-friendly option is upgrading deprecated APIs. These updates are highly appreciated because they improve the kernel’s maintainability and security. It’s not always a simple find-and-replace—you’ll need to understand the code—but it’s a rewarding way to start.
And don’t underestimate fixing spelling and grammar errors in the
documentation or comments. While it might sound trivial, it’s a
fantastic way to learn the workflow: creating patches, submitting them,
and receiving feedback. Tools like codespell can help you automate
finding these errors.
My first-ever patch was a simple typo fix, but I made the classic rookie mistake of introducing two changes while documenting only one. Lesson learned!
Once you start contributing, you’ll notice issues everywhere. Even just following discussions on LKML can teach you a ton about how seasoned developers think and work.
Conclusion
Kernel development might seem intimidating at first, but trust me, it’s worth the effort. You’ll not only become a stronger developer but also gain a deep understanding of how computers work. You’ll build expertise in both kernel and userspace development, and your Git skills will level up immensely—a must-have for any programmer.
The learning opportunities in kernel development are unparalleled, often rivaling (or even exceeding) those at top tech companies. So if you’re considering it, don’t hesitate—dive in! You might be surprised by how much you’ll grow.
Good Luck!
