names memory overlap error

Adam Lackorzynski adam at
Mon Sep 26 13:28:46 CEST 2005

On Mon Sep 26, 2005 at 00:41:01 -0700, Shakthi Kannan wrote:
> --- Adam Lackorzynski <adam at> wrote:
> > You can take the demo floppy image as a basis
> > ( Using
> > qemu is much more
> > comfortable.
> I tested the demo floppy on an old PIII desktop, and
> it booted fine. I also mounted it on my laptop and
> changed the images to the one I compiled (names, log,
> sigma0, rmgr, hello,...), and tested it on the
> desktop, and it worked fine.

Ok. When playing with OSes one either have a networked test box or
some virtual system. For the beginning and to explore the system qemu is
really good. Fiasco-UX will also work. You cannot have traditional
drivers with it (obviously) but it's a nice to get one going.

> > Another way to test things is Fiasco-UX, that's a
> > Fiasco running on
> > Linux.
> > When you say Linux drivers, do you mean DDE or
> > L4Linux? 
> I don't want to go through any
> virtualization/emulation/simulation. 

That's not really any of those. DDE is more about giving a Linux driver
the environment it expects (kmalloc, jiffies, interupts, etc.). Besides
that it's directly running on the kernel.
> Is it possible to write an application and device
> drivers (user-space) that interact directly with
> fiasco?

Sure this is possible.

> Are there any simple hello-world kind of
> examples or documentation for this?

There's the serial package which implements a lib to access the serial
port. It's only doing port-I/O though. To see how to attach to an IRQ
one could look at the input package or even L4Linux. To map device
memory we use a service called l4io.

> I have been looking for a microkernel to work/test
> directly with hardware. I don't need any fancy GUIs.
> Even a console with VGA output is fine.

If you do not want to have a GUI you do not get one :)

The VGA and serial output is what you're getting by default.

Adam                 adam at

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