On Fri, 2011-11-04 at 13:40 +0200, Michael S. Tsirkin wrote: > On Fri, Nov 04, 2011 at 08:14:43PM +1030, Rusty Russell wrote: > > > > 3) If we're changing the queue layout, it's a chance to fix a > > > > longstanding bug: let the guest notify the host of preferred > > > > queue size and alignment. > > > > > > Yup, we can do that. > > We don't need to change all of layout for that - just add another field > in the common config structure to supply the alignment. How would you do it without changing the layout? Add another optional field at the end which will shift offsets based on whether the host and guest support this new feature or not? This leads to 3 different things which now shift config offsets around. As you said, the PCI cap list was introduced both to save space (which is not the motivation here), and because it's a very efficient and easy way to manage optional features without requiring tricks which move offsets around like we do now. -- Sasha. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
