Subject: Re: UVM bug
To: Jason Thorpe <>
From: Neil A. Carson <>
List: tech-kern
Date: 05/26/1999 15:32:48
Jason Thorpe wrote:
> On Wed, 26 May 1999 15:14:20 -0700
>  "Neil A. Carson" <> wrote:
>  > I added an && (pos + size) onto the end of the test to fix this one I
>  > think.
>  >
>  > If this is correct, can someone commit it please?
> Actually, for various reasons, the VM system cannot handle the last page
> of physical memory, due to the way to denotes the "end" just about everywhere.
> I.e. a 4K region is 0x0000 -> 0x1000, NOT 0x0000 -> 0x0fff.

Hmm. So what's the way to reprogram something sitting in the top address
of phys RAM? IBM wired an AMD 512KB flash part there in one of their
more recent boards. Would it be safest to just pmap_kenter the page and
do it within the kernel? I'd better look at the code and see if even
_this_ will work...