Mork & Mindy

This afternoon after work, when I turned my computer on, I booted into a freshly compiled new version of Linux – 2.6.28 (with some patches provided by Gentoo). While in this particular instance, I had no need for a new kernel (2.6.26 was running fine), there is a satisfying feeling of knowing that you are completely up-to-date software wise.

What is a kernel you ask? Well, a kernel is the core of an operating system. It is the software the interfaces most directly with the hardware. One of the things that I love about Linux is the speed at which it is developed, its breadth of supported hardware/platforms (more than any other operating system, ever!) and the geeky feeling that you get deep down inside by knowing that you configured the kernel yourself – and it worked.

For those that aren’t familiar with the development process of Linux, it is run like many other open source projects. The source code (think of it as a software recipe) lives on a repository (think a library) on www.kernel.org and then thousands of developers from all over the world (yes really, you would be amazed by how many people develop this one piece of software, if you are interested, check out Greg K-H’s blog): edit, test, compile, break, bugfix, flame, discuss, commit. A new major release comes out about every 2-3 months, and always includes a plethora of new features (.28 has the ext4 filesystem marked as stable, the still-in-development .29 will have btrfs – a fancy next-gen filesystem).

The fun part comes once you have downloaded the kernel’s sources, extracted them to an appropriate place, and are ready to configure. The simple command make menuconfig will start up an interface that allows you to select the features you want. Knowing about the hardware in your computer is a must, but if you do, then assuming you aren’t running any ultra-new hardware, or rare exotic stuff, you should be able to correctly select the options that enable you to have a bootable kernel. Then a make && make modules_install to build the kernel, followed by copying it to the appropriate place and updating the bootloader, and all should be well in the state of Finland (why not Denmark? Well, Linus Torvalds, the creator of Linux and still the top-dog, is from Finland).

I have some strange desire to get into kernel programming one day, because I have seen some of the very cool things that some developers like Rusty Russell are capable of. But don’t worry, I don’t have a kernel fetish :P (in case you are wondering, I once came across a story of a developer who claimed to have printed out the source code of Linux, spread it on the floor and rolled around on it naked).