Linux 1.0.9 running!

After getting Linux 0.98 to compile, I thought I’d take a stab at Linux 1.0.  I vaugely recall when it was released, and I just remember a much larger push to 1.1.  So I guess it really comes as no surprise that in the Linux kernel archives, there is simply the 1.0 tar, and 9 patch files.

I went ahead, and patched up the release, and then tried to build with GCC 2.3.3.  This however proved not to be up to the task, as 2.3.3 has issues with some of the assembly macros, so delving into the readme shows that you need to use GCC 2.4.5 or higher.  Since I wanted to keep at least the tools on par, I went ahead and build 2.4.5, and once more again used the gcc driver from 2.6.3.  I further ended up relying on headers, and checking tool versions from Debian 0.91, which also revealed that they were still using GAS 1.38 back then.

One interesting note while building piggback, which takes the compressed system object, and wraps it in an object file, is that it directly uses the magic “0x00640107”, which is for a later “Linux/i386 impure executable (OMAGIC)” filetype.  But because my binutils is so ancient, I needed to change it to “0x00000107” so that the linker would recognize it as a “386 executable not stripped” file.  As always when having no idea what I was doing, it was easier to have it make an empty object file, set the type for 12345678 and look for where it occurs in the data stream, and just match it with a known object file.  As you can see, it worked.

I don’t know if it is of any interest, but the kernel source, along with a binary is available to download linux-1.0.9.7z, and the same goes for GCC gcc-2.4.5.7z.

And of course, you’ll want the latest download, which includes the pre-built tools, qemu, and build environment to get you started.

As we quickly approach this amazing milestone, I think it’s always interesting to re-visit the roots of Linux, back to the really ancient versions.  Thanks to the hard work of oldlinux.org, the oldest intact Linux source code available is Linux 0.10 from November of 1991.  A popular writeup on 0.10 was up on kerneltrap.org which appears to have been vaporized, but thanks to archvie.org is preserved.

Since this version is complete I thought it would be fun to run it through the Linux 0.11 build process & toolchain to see if I could get a working kernel.  Well I had a few stumbling blocks, the bootblocks and the keyboard assembly driver were giving me issues, and for the sake of time, I went ahead and replaced them with the code from 0.11, and along with minor patching to the IDE disk driver.  I added in a simple line to let me know I was actually booting up my franken 0.10 kernel with Qemu.  Also I found later versions of Qemu work much better with 0.10 regarding the IDE disk.

Linux 0.10 on Qemu, cross compiled on Windows

I know it’s not much to look at but it really is building and running.  I’m using the disk for the 0.11 series, as the userland seems to somewhat work.  It’s very touchy, and prone to crashing as it ‘has a bug in the buffer cache’ that I didn’t feel like trying to track down.  Nobody should be using this for anything serious anyways.

Install the 0.11 a.out GCC 1.40 on Win32 cross environment (I guess you can build them on Linux too if you so desire), and if you have a working MSYS environment you can run ‘make’ and it should give you a kernel.  The command file ‘linux.cmd’ will boot it up, and attach the disk image that I used to test.  There are permission errors, and well.. errors.  0.10 was not able to selfhost, but it should be enough to boot, mount the root, and run stuff like the sample ‘hello world’ program.

For those who like to browse the source, I have a browsable tree here.

And for the 2-3 people who care, here is my updated linux-0.10 source tree hosted on sourceforge.