Well, thre's nothing more to add than the contents in the subject. I tried booting up with -smp 2, and /proc/cpuinfo on the linux guest only return one CPU, while booting with "-smp 2 -enable-kvm" shows 2 CPUs.
Lluis -- "And it's much the same thing with knowledge, for whenever you learn something new, the whole world becomes that much richer." -- The Princess of Pure Reason, as told by Norton Juster in The Phantom Tollbooth
