Re: [Geekos-devel] Virtual Memory and ISA_HOLE

[David H. <da...@cs...>]

The only memory within the ISA hole that geekos uses is the
text video memory, which is at physical address 0xB8000.
You should ensure that the physical page at that address is
mapped into the kernel region of every address space.
(1 page suffices because the text screen is 80x25, and 2 bytes
are used for each character).

-Dave

On Sun, Nov 18, 2001 at 02:14:50AM -0500, Patrick Sodre Carlos wrote:
> 
> Hi Dave,
>    
>    Its me bugging you again. I have this "stupid" doubt about the pages
> reserved for the HardWare and how they interact with the pagin scheme. I
> understand that the upper 256 pages that correspond to the area reserved 
> for the kernel must be "copied" to every other page directory. Now, my
> doubt is whether or not to copy/map the pages reserved for the ISA_HOLE. I
> believe that they must be mapped in the kernel master page directory, but
> I'm not sure if they must be mapped in the User Page Directory as well. I
> read one manual on the i386 but I could not find anything related to that.
> 
>    If you know any document which might contain this type of info, or if
> you know the answer please tell me :)
> 
> Regards,
> Patrick Sodre 
> 
> 
> _______________________________________________
> Geekos-devel mailing list
> Gee...@li...
> https://lists.sourceforge.net/lists/listinfo/geekos-devel