Physical address

[Die Gestalt]

What I did is start a VMWare running FreeBSD, boot and freeze at
logon, open the vmem file in a Hex editor and see that there is stuff
between 0x1000 - 0x4000. The memory is clear (as expected) after
0x4000 till the kernel (after the first megabyte).

I have no idea what it is and where it comes from, especially since I
think pages are cleared when mapped, right? That would mean that it
cannot be a residue from the boot sequence (unless I'm wrong).

Any idea?

-- 

Die Gestalt

On 9/5/07, Die Gestalt <die.gestalt at gmail.com> wrote:
> Hi all,
>
> I would like to know if there are drivers in a vanilla FreeBSD kernel
> that write to *physical* memory addresses between 0x1000 and 0x4000.
>
> From what I inderstand the region between 0x1000 and the first
> megabyte is mapped read only, but that doesn't prevent you from
> accessing the region if you really want to.
>
> Hope my question makes sense.
>
> --
>
> Die Gestalt
>