Re: [Qemu-devel] [PATCH 4/8] qdev/core: bus list

[Paul Brook <paul@codesourcery.com>]

> >>> The address of the BusState is also a locally unique
> >>> identifier. That doesn't mean it's a good thing to expose to the
> >>> user.
> >>
> >> Red herring.
> >
> > I don't think that's a very useful response.
> >
> > I think it's a perfectly valid suggestion that we should identify
> > buses based on the their location in the tree to users verses a number
> > generated based on some hashing algorithm.
> >
> > A tree location has meaning to a user.  A random integer doesn't.
>
> Numbering nodes according to a well-defined tree traversal is not
> random.  We can discuss whether using such a number in an interface is a
> good idea (nobody suggested to use it *instead* of tree paths).

I don't believe the tree traversal order is well defined. While developing the 
qdev patches I went through two or three different traversal algorithms. It 
gets even hairier when you start considering hotplug.

Paul