Re: [uml-devel] cygnus-win32 port of User Mode Linux

[Erik P. <epa...@cs...>]

On Fri, Dec 08, 2000 at 05:50:40PM -0500, Michael Vines wrote:
> > > If that is the case, then what is stopping the
> > > application from peaking into UML?   
> > 
> > Nothing now, but I'm going to make it protect (or unmap) the kernel whenever 
> > it's in userspace.  That will make it impossible to fiddle kernel data from 
> > the process, and that will make it a fairly secure jail.
> 
> That sounds like a pretty severe performance hit.  
> 

It can't be much worse than ptracing, rewriting the system call, making a new
system call, and then returning.

-Erik