Subject: Re: random signals kill my processes with -current
To: Chris G. Demetriou <>
From: Perry E. Metzger <>
List: current-users
Date: 01/27/1997 17:19:13
"Chris G. Demetriou" writes:
> > The 4.4 book claimed that most 4.4. ports already had a guard page at
> > the end of the kernel stack -- I was unaware that this was not the
> > case any longer.
> Quite honestly, I don't believe this.

Hey, I'm only reporting what I read. By coincidence, I was looking
over the section on the u. area two nights ago, and I remember this
being mentioned.

> > I would feel much more comfortable if we had them -- this silent
> > overflow thing may be leading to all sorts of inexplicable problems
> > (and not just during autoconfig).
> I don't disagree with this.  It's just not quite as simple to
> implement as one might like.  8-)

That I understand.

> > At least, though, we might learn that we need to expand the stack by a
> > page, or that we have a kernel bug wasting kernel stack. I prefer to
> > know than not knowing.
> Actually, what we'd end up seeing is spontaneous reboots.
> figuring out what's causing an apparently- spontaneous reboot can
> be ... difficult.  8-)

No way at all to gracefully deal with the fault when we hit the
unmapped page?