> You are correct, of course.  If "isolcpus" is used, the isolated
> cpu(s) (in <cpu_isolated_map>) are not init like the remaining
> cpus are.
>
> I don't know what's intended here... but it's not the divide by 0.

A patch is attached which fixes problems with isolated
domains for me. I hope it is correct :-) I will try on
real SMP when I will be in work (now it boots on Boochs).

enjoy,

    Martin Devera aka devik
Linux kernel QoS/HTB maintainer
  http://luxik.cdi.cz/~devik/