biodone panics

[Alex Lyashkov]

> 
> the call to wakeup may set in motion some events that cause the bio to
> be freed. By the time the mtx_unlock completes, "bp" could point to an
> invalid bio, and the "if (bp->bio_done != NULL)" is bogus. True?
> Shouldn't it be
> 
> > biodone(struct bio *bp)
> > {
> >         void (*done)(struct bio *);
> >
> >         mtx_lock(&bdonelock);
> >         bp->bio_flags |= BIO_DONE;
> >         done = bp->bio_done
> >         if (done == NULL)
> >                 wakeup(bp);
> >         mtx_unlock(&bdonelock);
> >         if (done != NULL)
> >                 bp->bio_done(bp);
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
posible 
if( done != NULL )
	done(bp);
?
> > }
> 
> Anyone agree?