Ingo, all

I, silly person that I am, configured an RT, SMP, PREEMPT_DEBUG system. 
  Someone put code in the NMI path to modify the preempt count which, 
often as not will generate a PREEMPT_DEBUG message as there is no tell 
what state the preempt count is in on an NMI interrupt.  I have sent the 
attached patch to Andrew on this, but meanwhile, if you want RT, SMP, 
PREEMPT_DEBUG you will be much better off with this.
-- 
George Anzinger   george@mvista.com
HRT (High-res-timers):  http://sourceforge.net/projects/high-res-timers/