yamt@mwd.biglobe.ne.jp writes:
> 	softupdate calls reassignbuf(), which modifies v_flag,
> 	via bdirty() from interrupt context.

This is not just a soft update problem.  It also happens on
io error.  This is an instance of some of the problems I mentioned
on tech-kern last March:

  http://mail-index.netbsd.org/tech-kern/2004/03/03/0003.html

I haven't done anything towards a fix since I sent that mail,
although I thought it might be useful to reference it in the pr.

Darrin