hang on revivesa with dual core CPU

[David Brownlee <abs%absd.org@localhost>]

        I've been testing a current revivesa kernel (built from
        sources updated today) on several NetBSD 4.0_STABLE installs,
        and everything seems to be happy on the single core boxes
        (firefox3, gnash, pidgin, ktorrent3, apache, etc), but I've
        seen several hard lockups when running on an MP box (Thinkpad
        T60p Intel Core 2 T7400).

        I've been able to fire up ktorrent3 and CTRL+ALT+F1 back
        to the console before the hang so I've been able to verify
        it doesn't panic or drop into DDB - to the extent that
        CTL+ALT+ESC has no effect.

        A kernel with 'no cpu* at mainbus?', 'cpu0 at mainbus?' to
        disable the second core seems to be happy (so far).

        Has anyone else seen similar?