Re: Configuration vs. compat hints [was Re: [Qemu-devel] [PATCHv3 03/13] qemu: add routines to manage PCI capabilities]

[Avi Kivity]

On 06/16/2009 03:14 PM, Mark McLoughlin wrote:
> On Mon, 2009-06-15 at 13:12 -0500, Anthony Liguori wrote:
>    
> > Mark McLoughlin wrote:
> >      
> > > So long as the restrictions would be known to the management app via
> > > some "what slots are available" mechanism in qemu, that sounds fine.
> > >
> > >        
> > I'm not sure a "what slots are available" mechanism is as straight
> > forward as has been claimed.
> >      
>
> If qemu can't provide that information, then the management app does not
> have sufficient information to do the slot allocation itself. In which
> case, it must leave it up to qemu to do it.
>    

A given -M machine will have well-known open slots (since it's an ABI), 
same as it has rtl8139 and ne2000 cards.  Worst case we hardcode those 
numbers (gasp, faint).

> > It doesn't matter though because it's orthogonal to the current proposal.
> >      
>
> It is not orthogonal to solving the actual problem at hand, though -
> i.e. how to allow management apps to provide stable PCI addresses.
>    

It's part of the solution, but hardly a difficult the most difficult part.

> This is a fine solution to the "stable guest ABI" problem ... assuming
> there's some way of querying the current default machine type.
>    

    $ qemu -print-default-machine

or maybe

    $ qemu -show default-machine
    $ qemu -show pci-bus
    $ qemu -show me a way out

--
error compiling committee.c: too many arguments to function