Re: Lguest

[Rusty Russell <rusty@rustcorp.com.au>]

On Thu, 2007-06-28 at 19:03 +0200, Matias Zabaljauregui wrote:
> Hello Rusty, 
> 
> I'have just started to read the code (and I'm not an expert kernel
> programmer), but is this condition ok ?
> 
> 
> (function setup_pagetables(), on file Documentation/lguest.c )
> 
>     /* Ideally we map all physical memory starting at page_offset. 
>      * However, if page_offset is 0xC0000000 we can only map 1G of
> physical
>      * (0xC0000000 + 1G overflows). */
> 
>     if (mem > -page_offset)
>         mapped_pages = mem/getpagesize();
>     else
>         mapped_pages = -page_offset/getpagesize(); 

Hi Matias,

	I think so: these are unsigned values, so "-page_offset" is the address
space available for kernel memory (usually 1G).  It's a little
strange-looking, I admit.

Hope that helps,
Rusty.