Subject: Re: random signals kill my processes with -current
To: Jason Thorpe <email@example.com>
From: Perry E. Metzger <firstname.lastname@example.org>
Date: 01/27/1997 17:15:42
Jason Thorpe writes:
> On Mon, 27 Jan 1997 16:49:21 -0500
> "Perry E. Metzger" <email@example.com> wrote:
> > 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.
> So, the hp300 port had this long ago... it was a bit easier to do
> in 4.4BSD because of the double-mapping of the kernel stack. I.e.
> the "guard page" address never changed, because the kernel stack
> for all processes was mapped to the same address (kstack) upon
> context switch.
> When kstack went away, the stack checking stuff was garbage-collected.
This sounds, though, like its something that might be worth bringing
back if it can be done. For all we know, lots of weird bugs would
suddenly be found.