> > If you want to get rid of this hack in a proper way, it would be
> > to store an "mpsafe" attribute in the handler structure, always
> > call a stub function, and have that take the lock depending
> > on the flag.
> >
> > Of course, for that, all intr_establish functions need an extra
> > flag passed in, and all device drivers must be changed to use it..
> 
> i agree that it's cleaner.

however, i'm not sure about usefulness of an extra flag for
intr_establish.
"ipl < somevalue" check in intr_establish is needed anyway because,
if an interrupt handler is not mpsafe, all interrupt handers having
lower ipl than it need to acquire kernel lock regardless of
their own mpsafeness.

YAMAMOTO Takashi