Re: [Qemu-devel] [PULL 1/2] qxl: store channel id in qxl->id

[Gerd Hoffmann]

  Hi,

> >      vga->con = graphic_console_init(DEVICE(dev), 0, &qxl_ops, qxl);
> > +    qxl->id = qemu_console_get_index(vga->con); /* == channel_id */
> > +    if (qxl->id != 0) {
> > +        error_setg(errp, "primary qxl-vga device must be console 0 "
> > +                   "(first display device on the command line)");
> > +        return;
> > +    }
> 
> In the comment this seems no more required so why testing it?

I'd expect it'll confuse guests.

If you are sure this is not the case feel free to send a patch dropping
this check.

> >  static void qxl_realize_secondary(PCIDevice *dev, Error **errp)
> >  {
> > -    static int device_id = 1;
> >      PCIQXLDevice *qxl = PCI_QXL(dev);
> >  
> > -    qxl->id = device_id++;
> >      qxl_init_ramsize(qxl);
> >      memory_region_init_ram(&qxl->vga.vram, OBJECT(dev), "qxl.vgavram",
> >                             qxl->vga.vram_size, &error_fatal);
> >      qxl->vga.vram_ptr = memory_region_get_ram_ptr(&qxl->vga.vram);
> >      qxl->vga.con = graphic_console_init(DEVICE(dev), 0, &qxl_ops, qxl);
> > +    qxl->id = qemu_console_get_index(qxl->vga.con); /* == channel_id */
> >  
> 
> As these IDs must be contiguous this means that there must be the requirement
> that if there is a qxl interface only qxl interfaces are used and no other
> console which seems to me wrong.

Hmm.  Didn't know this is a requirement.  But as far I know qxl->id is
also expected to be the channel_id.  So with qxl and non-qxl mixed we
are in trouble no matter what:

  * with the patch we break the contiguous id requirement.
  * without the patch we break the qxl->id == channel_id requirement.

So, what now?

cheers,
  Gerd