Re: UVM and the NULL page

[Paul Goyette <paul%whooppee.com@localhost>]

On Fri, 29 Jul 2016, Joerg Sonnenberger wrote:

> On Fri, Jul 29, 2016 at 10:08:48AM +0200, Maxime Villard wrote:
> > It is not possible to keep a sysctl, since VM_MIN_ADDRESS is a constant
> > used in assembly, so it won't be turned to a variable.
>
> So find a different solution to fix the bugs.
>
> > Now, it is a little hard to know how many emulators or whatever rely on
> > null to be available. But many (most?) systems don't allow null nowadays,
> > and null dereferences are a well-known issue. It is more or less becoming
> > a standard. If a software fails on NetBSD because of a null mmap, then it
> > is likely to fail on many other systems.
>
> Just because many newer ("hardened") systems break compatibility with
> existing programs doesn't justify the same to be done to NetBSD.
>
> > I will commit [3] soon.
>
> I strongly object that.

I also object.


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