Re: Fwd: [Introspector-developers] status report

[Marcus Brinkmann]

On Sat, Oct 18, 2003 at 03:13:59AM -0700, James Michael DuPont wrote:
> > Yes, it is very consistent and abstract.  But, it is also incredible
> > slow
> > and resource heavy, and enforces a lot of policy on the user.  This
> > slows
> > down the fast path, and introduces some interesting DoS attacks.
> 
> OK, do you think that we can add in specific transformations and rules
> into the compiler that will allow us to optimize some of this out? I
> do.

No, it's not possible.  The problems are not in the implementation or
whatever local optimizations are possible, but in the interface design.

[...]

> What about a port registration utility that allows users to define
> ports to be bypassed via simple function calls and to define the
> semantics better? In a network environment you will want to have a
> client certificate to be attached to the port to know who is attaching.

Adding more features to the kernel will only make the matter worse.
Any particular addition can fix the one or other security problem, but by
adding even more costs.

> So what do you plan on doing?

We are working on a redesigned port to the L4 microkernel (www.l4ka.org).

> > 
> > And the Hurd is not difficult to compile either :)
> 
> No, it was quite easy once I cleaned out the mach code, I dont see why
> the entry costs for compiling should be so high?

The entry cost for compiling is installing the Hurd, or installing a vanilla
cross compiler.  You did some odd, I have no clear idea what, but it was
only complicated because you ignored the standard paths.

> Cannot mach/hurd run
> in user mode and be implemented as a set of linux constructs?

For Mach, probably.  Can BSD be compiled and run on Linux?  Can Windows be
compiled and run on OS/2?  Maybe.  It's not part of our project.

And it has nothing to do with the Hurd.  The Hurd needs the Mach headers,
point.  If you build a user space Mach for Linux, you still have to install
a cross compiler and the Mach header files.

The Hurd can _not_ run directly on Linux, and with high certainity never will.

> at least
> for the libstore and libstream/channel it should be possible to test it
> under linux.

I think you have still no clear idea what you are talking about.  Only parts
of that just need simple device access, others need the ports functionality.
The same can be said of every software.  Parts of ext2fs translator can run
on Linux, but the whole can not.  It's just a broken idea from the start.

Thanks,
Marcus

-- 
`Rhubarb is no Egyptian god.' GNU      http://www.gnu.org    marcus@gnu.org
Marcus Brinkmann              The Hurd http://www.gnu.org/software/hurd/
Marcus.Brinkmann@ruhr-uni-bochum.de
http://www.marcus-brinkmann.de/