Re: [Qemu-devel] No more chameleon devices

[Eduardo Habkost]

On Thu, Oct 18, 2018 at 03:38:58PM +0100, Daniel P. Berrangé wrote:
> On Thu, Oct 18, 2018 at 03:15:31PM +0100, Peter Maydell wrote:
> > On 18 October 2018 at 15:11, Marcel Apfelbaum
> > <address@hidden> wrote:
> > > Maybe would be a step toward a clean "socket-device" modeling (what goes
> > > where)
> > > and also QEMU emulation would be cleaner since in bare metal you cannot
> > > plug a PCIe device into a PCI slot and vice-versa or have the same device 
> > > ID
> > > for both a PCI and a PCIe device.
> > 
> > So the command line would then distinguish "-device ne2k-pci" and
> > "-device ne2k-pcie", and users need to know whether the machine they're
> > using implements PCI or PCIe, and use the right device name accordingly?
> 
> I can understand the rational for splitting the virtio devices, because
> of the way they completely change their functionality, even PCI device ID,
> depending on whether plugged into a pci or pcie slot.
> 
> I'm not seeing the real world benefit of creating -pci vs -pcie for all
> the other non-virtio devices. AFAIK, the existing devices work the same
> regardless of what bus they are plugged into. So why would a user/app
> want to use such devices ? It feels like extra work for no clear benefit

Agreed.

-- 
Eduardo