Re: Configuring onboard devices (was: Failing property setters + hardwired devices + -global = a bad day)

[Peter Maydell]

On Thu, 30 Apr 2020 at 11:34, Daniel P. Berrangé <address@hidden> wrote:
> We "merely" need a new query language targetted to QEMU's qtree
> structure, which we can expose in the CLI that gives unique access
> to every possible property.

Past resistance to this has been grounded in not wanting to
expose the exact arrangement of the qtree as a user-facing
thing that needs to be maintained for back-compat reasons.

Eg in your example the i440fx-pcihost sits directly on the
'system bus', but this is an odd artefact of the old qbus/qdev
system and doesn't really reflect the way the system is built
up in terms of QOM components; we might one day want to
restructure things there, which would AIUI break a
command line like

> To uniquely identify this we can have a string:
>
>  
> /dev[1]/bus[pci/0]/dev[id=balloon0]/bus[virtio-bus]/dev[0]/deflate-on-oom=true

thanks
-- PMM