Re: [Qemu-devel] [PATCH 3/6] virtio-console: Add a virtio-console bus, support for multiple ports

[Gerd Hoffmann <kraxel@redhat.com>]

On 10/07/09 13:42, Amit Shah wrote:
> On (Wed) Oct 07 2009 [13:33:57], Gerd Hoffmann wrote:
>> Second, the bus= argument is optional.  If not specified, qdev will pick
>> the first bus of a matching type it finds.  So as long you have a single
>> port/scsi/usb/... bus only you don't need bus= at all.  You can do:
>
> The problem with this is that the management solution needs to know then
> what is the default bus name (which could change if the code gets
> updated).

No problem.  Just don't use -virtioconsole.  Go with -device 
virtio-serial-bus,id=... + -device virtport,bus=.. then and explicitly 
name your devices (and thereby the buses too).

-virtioconsole should *really* be a pure backward compatibility thing. 
Use case:  You have a script starting qemu using -virtioconsole.  After 
upgrading qemu it should continue to work, i.e. create a device which 
the guest can use as before the upgrade and which is linked up to a 
chardev as it was before.

Anything which wants to use the new features can (and should) completely 
ignore -virtioconsole.  I just wanted to point out that mixing old and 
new style is *possible*.  It wasn't my intention to imply that I 
*recommend* doing that.

> And also there's the other problem of a console port spawning a bus
> (which could end up spawning another console port at #0...)

parse error.
I don't understand what problem you are trying to point out.

cheers,
   Gerd