On Sat, 2007-09-22 at 12:01 +0200, Arnd Bergmann wrote: > On Saturday 22 September 2007, Rusty Russell wrote: > > But now each virtio device has two "struct device"s, not one. And > > you've made up a fictional bus to do it. > > > > Yet for PCI systems, it really is a PCI device; exposing a second bus to > > userspace just because we put a layer in our implementation is poor > > form. > > > > Perhaps this is the easiest way of doing it. But it's still wrong. > > I think it's just a matter of perspective. In the model I'm advocating, > the PCI device is not the same as the virtio device but rather a virtio > host bridge, very much like USB or SATA works. > > We could easily have multiple virtio devices behind one PCI device, but > since virtual PCI devices are cheap, a one-to-one mapping makes sense > for simplicity.
This is still retro-justification. The simplest way for PCI systems to represent a virtio device as a PCI device; this makes life easy for any guest OS. I just know we're going to regret this... Rusty. ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ kvm-devel mailing list kvm-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-devel