Re: [Qemu-devel] Re: [PATCH] Add -no-virtio-balloon command-line option

[Dor Laor]

Anthony Liguori wrote:
> Markus Armbruster wrote:
> > Dor Laor <address@hidden> writes:
> >
> >  
> > > Gerd Hoffmann wrote:
> > >    
> > > > > This new option may be used to disable the virtio-balloon device.
> > > > >
> > > > >         
> > > > ACK, looks good.
> > > >
> > > > And I can drop my lazy patch which just comments out virtio-balloon
> > > > in the code ;)
> > > >       
> > > Actually, I rather have the balloon disabled by default. It's like any
> > > other pci device which needs
> > > explicit command line specification. Why consume a pci slot if not
> > > implicitly required?
> > >     
> >
> > I agree.  The command line is plenty magic without implicitly added
> > PCI devices.
> >
> > Besides, negative options -no-virtio-balloon lead to ugly
> > double-negatives like if (!no_virtio_balloon).
> >   
>
> It does no harm to add the device by default so why force the user to 
> explicitly enable it?

It consumes one of the 32 pci devices we have today. It's the same for 
not having -usb as default
or any other type of device. Soon we'll need pci_addr= along with it 
anyway ;)

Dor