[Qemu-devel] linux-test image for user-net?

[Qemu-devel] linux-test image for user-net?

[Stealth Dave]

Is it possible to build a linux-test image that enables network access 
via user-net instead of tun/tap?  I'm trying to build a special-purpose 
and very minimal linux distro for use with QEMU, and the linux-test 
image looks like a very good place to start.  Is there any 
documentation on how the image was built, what packages/software is 
included, etc?  Is enabling user-net support as simple as compiling a 
new kernel with the proper modules?  While I've been using Linux for 
about 6 years now and consider myself a skilled user, this is my first 
attempt at building any kind of linux system.  Any help would be 
appreciated.

Thanks,
- Dave

Re: [Qemu-devel] linux-test image for user-net?

[Paul Brook]

On Tuesday 15 November 2005 20:36, Stealth Dave wrote:
> Is it possible to build a linux-test image that enables network access
> via user-net instead of tun/tap?

The guest OS doesn't care whether qemu is using user-net or tun-tap.
The linux-test image downloadable from the qemu website doesn't work properly 
because it only contains the ISA ne2k driver, and qemu now emulates a
PCI ne2k card.

Paul

Re: [Qemu-devel] linux-test image for user-net?

[Jamie Lokier]

Paul Brook wrote:
> On Tuesday 15 November 2005 20:36, Stealth Dave wrote:
> > Is it possible to build a linux-test image that enables network access
> > via user-net instead of tun/tap?
> 
> The guest OS doesn't care whether qemu is using user-net or tun-tap.
> The linux-test image downloadable from the qemu website doesn't work
> properly because it only contains the ISA ne2k driver, and qemu now
> emulates a PCI ne2k card.

Perhaps qemu's PCI ne2k emulation could be changed to accept accesses
to the I/O addresses of the classic ISA card too - and disabling the
PCI addresses if an OS touches the ISA ones?  Old OSes which only know
about ISA ne2k would work, and newer ones which enumerate it through
PCI would also work.

-- Jamie

Re: [Qemu-devel] linux-test image for user-net?

[Paul Brook]

On Tuesday 15 November 2005 20:49, Jamie Lokier wrote:
> Paul Brook wrote:
> > On Tuesday 15 November 2005 20:36, Stealth Dave wrote:
> > > Is it possible to build a linux-test image that enables network access
> > > via user-net instead of tun/tap?
> >
> > The guest OS doesn't care whether qemu is using user-net or tun-tap.
> > The linux-test image downloadable from the qemu website doesn't work
> > properly because it only contains the ISA ne2k driver, and qemu now
> > emulates a PCI ne2k card.
>
> Perhaps qemu's PCI ne2k emulation could be changed to accept accesses
> to the I/O addresses of the classic ISA card too - and disabling the
> PCI addresses if an OS touches the ISA ones?  Old OSes which only know
> about ISA ne2k would work, and newer ones which enumerate it through
> PCI would also work.

You can tell qemu to emulate an isa only system. 
Having the same [virtual] hardware respond to both ISA and PCI is a bad idea. 
It'll break horribly as soon as an OS loads both drivers.

Paul

Re: [Qemu-devel] linux-test image for user-net?

[Ben Taylor]

Stealth Dave <dave@triplecatproductions.com>


> Is it possible to build a linux-test image that enables network access 
> via user-net instead of tun/tap?  I'm trying to build a special-purpose 
> and very minimal linux distro for use with QEMU, and the linux-test 
> image looks like a very good place to start.  Is there any 
> documentation on how the image was built, what packages/software is 
> included, etc?  Is enabling user-net support as simple as compiling a 
> new kernel with the proper modules?  While I've been using Linux for 
> about 6 years now and consider myself a skilled user, this is my first 
> attempt at building any kind of linux system.  Any help would be 
> appreciated.

The only difference should be in the configuration of
the networking, right?  Instead of a fixed address with
tun/tap, just turn on dhcp and the qemu client will 
pickup 10.0.2.15, assuming you start qemu with -user-net.

Ben