> I've just built a 1.6.1_RC1 kernel with strongarm optimizations enabled, 
> but with bcopyinout.S pulled up to revision 1.6 and the kernel seems fine 
> (sufficient to completely bootstrap and regtest gcc without any untoward 
> problems).
> 

It appears I may have spoken too soon on this.  Building X last night lead 
to a number of core dumps which I wasn't seeing while bootstrapping gcc.  
None of the core files seems to indicate that the application was at 
fault, and rerunning one of the failed compiles did not core a second time 
(only had time to try one).

Looking at the pmap.c log file I see that several patches related to 
cacheing page-table entries have been pulled up.  I'll try backing out 
some of those tonight unless someone can identify what is missing between 
the branch and current, which doesn't seem to have this instability.

Jason, any ideas?

R.