virtio — archive

Feedback: PCI device spec

From: Rusty Russell <[email protected]>
To: [email protected]
Date: Wed, 29 Jan 2014 02:46:00 -0000

Pawel Moll <[email protected]> writes: > On Tue, 2014-01-28 at 16:58 +0000, Michael S. Tsirkin wrote: >> ATM you can put any value that makes sense there I think, drivers will bind >> and work. > > That's true, I'm fine with this. > > But try to put yourself into such guy's shoes. You know nothing about > virtio. You have to implement a virtio PCI device for your custom > system. You're looking at the PCI spec, which tells you that you've got > to put some values into the device's configuration space. And the virtio > spec doesn't tell you what numbers should you use. > > I appreciate it's convenient for us not to specify such details. Maybe > it's the right thing to do. But I also understand my colleague's > frustration with this aspect of the spec. Thus the discussion. This. The spec *exists* so we get more, good implementations. What helps this? Including a non-normative paragraph discussing use of PCI class? Or ignoring it and leaving implementers confused and frustrated so we look more rigorous? In fact, let me now offer a beer to anyone on the committee who adds a decent joke to the spec. Because the spec is for humans, and I want readers to like it so much they tell their friends to implement it. Thanks, Rusty.