Re: [Qemu-devel] [PATCH 6/6] docs: add multiseat.txt

[Gerd Hoffmann]

  Hi,

> > If there is anything to configure then it most likely will be ui
> > specific, i.e. we could possibly allow something like this ...
> >
> >    -display gtk,display=video.1 \
> >    -vnc :0,display=video.2
> >
> > ... to have one head show up on gtk and the other on vnc (needs '-vga
> > none -device VGA,id=video.1' instead of '-vga std').
> 
> How would you configure the case where one input goes to multiple heads 
> (e.g. 2 seats, 4 monitors)?

You need one keyboard per head (i.e. 2) and one tablet per display (i.e.
4).  The usb tablet has a additional head property, so you can specify
which tablet belongs to which monitor.  You also need a vga card which
supports multiple heads (non-upstream virtio-gpu will do).

Not figured yet how to do guest configuration (teach X server which
tablet belongs to which monitor) for the multihead case.

Note: qxl supports multi-head already, but can't be used for this as it
goes spice-specific side ways to get the job done.  Fixing that is on my
todo list, but it isn't trivial, especially the backward compatibility.
Probably also needs spice-server changes.

cheers,
  Gerd