This program causes an instant panic for me:

        #include <sys/mman.h>
        
        int main(int argc, char **argv)
        {
        	munmap((char *)(((unsigned long)&argc) & ~4095), 4096*2);
        
        	return 0;
        }

I'm not sure if setting the signal handler is necessary or not.  My
environment is largeish, so the stack is 2 pages; you might need to
adjust it.

There's a message on the console saying something like "panic: bad pgd:
0x00000e13".  It was a bit too quick to see.

Plain 2.6.10 segfaults as expected; I haven't tried -mm1 to see what it
does.

Config attached.

	J