Subject: Re: map user memory in kernel
To: None <tech-kern@netbsd.org>
From: Joerg Sonnenberger <joerg@britannica.bec.de>
List: tech-kern
Date: 11/05/2005 17:03:19
On Sat, Nov 05, 2005 at 03:32:00PM +0000, Emmanuel Dreyfus wrote:
> On Sat, Nov 05, 2005 at 12:22:45PM +0100, Wolfgang Solfrank wrote:
> > So no need to actually map the page into memory.  Just make a more or
> > less unique address out of the address given (like e.g. use the physical
> > address on machines where physical and virtual address sizes match) and be
> > done with it.
> 
> But what if the page where the address is gets paged out? I can't 
> rely on a physical address in that situation.

What about explicitly wiring the page and using the normal ulimits to
decide when this breaks?

Joerg