Re: [Qemu-devel] Re: virtio-serial: An interface for host-guest communication

["Daniel P. Berrange" <berrange@redhat.com>]

On Thu, Aug 20, 2009 at 07:12:41PM +0530, Amit Shah wrote:
> 
> I've now seen some more code here and to me it looks like virtioconsole
> is not used on any of the guests that qemu supports. The virtio_console
> kernel module only works with lguest and s390 currently. There is one
> feature and some config values supported by the kernel module but not in
> qemu.
> 
> So it looks as if we have virtio-console merged but no one uses it. Is
> this right?

Nope. Grab a Fedora 11 live CD, and boot with

  # qemu-kvm -virtioconsole stdio -cdrom Fedora-11-i686-Live.iso  -m 500

Once it completes booting & logs into gnome, open a terminal and run
as root

   agetty /dev/hvc0 9600 vt100  

You'll get a login prompt on the host machine now.

What appears to not be working, is early kernel boot messages. eg, I
ought to be able todo

  # qemu-kvm -virtioconsole stdio -kernel vmlinuz -initrd initrd.img \
      -append "console=hvc0"  -m 500

and see the kernel boot messages, but this doesn't work with Fedora
kernels at least. Not tried upstream, or looked to see if this is just
an oversight in the Kconfig use for Fedora kernels.

Regards,
Daniel
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