Kernel panics

Today, I tried and finished the RTAI kernel. First, I got hold of a vanilla 2.6.23 kernel. It took quite a while to create a minimal, working configuration. Part of that was because of me not realizing the sheer amount of new options which nest deeply in the configurations.

When it finally ran, I got the latest RTAI-distribution, and tried to start. The RTAI-Wiki suggested some ADEOS-patch to apply, so I investigated that. But it turns out that RTAI is based on it's own fork of ADEOS, which I grasped after finding this fine RTAI-tutorial.

So I patched the kernel. Or tried to.For some reason some things called "ipipe" weren't working in the patch. Finally, I found that because of the misapplied original ADEOS-patch
my vanilla kernel sources first had to make a run for themselves, with the effect of creating the files necessary for the "ipipe"-stuff. After that, the patching went flawlessly, and I was able to build a kernel.

Rebooting into it, I started building RTAI itself. At this point, it puked on me for not having CONFIG_MODVERSIONS disabled. I'm sure that is told you somewhere, but I missed it. So it was recompiling the kernel again.

After than, the next hurdle was that I used GCC 4.1, but the RTAI-Lab didn't work with that. I removed it from the configuration, as for now I'm not really interested in it. A view I got to question sometime in the future.

Building went smooth afterwards. Naturally, that wasn't all there was to it. When trying to run the latency-tests, the loading of the kernel modules failed muttering about APIC being enabled but not available. I found this discussion about it, but didn't get the enlightenment I hoped for.

So I disabled the APIC in the kernel, and recompiled. I wish I had a Euro for each time I recompiled the kernel in the last few days...

In the end, it didn't help - but after reading this, adding lapic to my kernel boot parameters did the trick.

I finally have a working testsuite of RTAI. Whopee!

Now all I need to do is to make that kernel run on the Robots own board. And then add WIFI support for it.