Re: [PATCH v2 2/3] qom: move user_creatable_add_opts logic to vl.c and QAPIfy it

[Kevin Wolf <kwolf@redhat.com>]

Am 13.04.2021 um 10:13 hat David Hildenbrand geschrieben:
> On 13.04.21 06:41, Markus Armbruster wrote:
> > David Hildenbrand <david@redhat.com> writes:
> > 
> > > On 12.03.21 18:35, Paolo Bonzini wrote:
> > > > Emulators are currently using OptsVisitor (via user_creatable_add_opts)
> > > > to parse the -object command line option.  This has one extra feature,
> > > > compared to keyval, which is automatic conversion of integers to lists
> > > > as well as support for lists as repeated options:
> > > >     -object
> > > > memory-backend-ram,id=pc.ram,size=1048576000,host-nodes=0,policy=bind
> > > > So we cannot replace OptsVisitor with keyval right now.  Still, this
> > > > patch moves the user_creatable_add_opts logic to vl.c since it is
> > > > not needed anywhere else, and makes it go through user_creatable_add_qapi.
> > > > In order to minimize code changes, the predicate still takes a
> > > > string.
> > > > This can be changed later to use the ObjectType QAPI enum directly.
> > > > 
> > > 
> > > Rebasing my "noreserve"[1] series on this, I get weird errors from
> > > QEMU when specifying the new "reserve=off" option for a
> > > memory-backend-ram:
> > > 
> > > "Invalid parameter 'reserve'"
> > > 
> > > And it looks like this is the case for any new properties. Poking
> > > around, I fail to find what's causing this -- or how to unlock new
> > > properties. What is the magic toggle to make it work?
> > > 
> > > Thanks!
> > > 
> > > [1] https://lkml.kernel.org/r/20210319101230.21531-1-david@redhat.com
> > 
> > Wild guess: you didn't add your new properties in the QAPI schema.
> > 
> > For a not-so-wild-guess, send us a git-fetch argument for your rebased
> > series.
> > 
> 
> Oh, there is qapi/qom.json -- maybe that does the trick.
> 
> (I have mixed feelings about having to specify the same thing twice at
> different locations)

The idea is that we'll eventually generate some of the QOM boilerplate
from the QAPI schema and remove the duplication again.

But yes, for the time being, you need to touch both places.

Kevin