Re: [PATCH v2 00/15] qdev: Add JSON -device

On Fri, Oct 08, 2021 at 03:34:27PM +0200, Kevin Wolf wrote: > It's still a long way until we'll have QAPIfied devices, but there are > some improvements that we can already make now to make the future switch > easier. > > One important part of this is having code paths without QemuOpts, which > we want to get rid of and replace with the keyval parser in the long > run. This series adds support for JSON syntax to -device, which bypasses > QemuOpts. > > While we're not using QAPI yet, devices are based on QOM, so we already > do have type checks and an implied schema. JSON syntax supported now can > be supported by QAPI later and regarding command line compatibility, > actually switching to it becomes an implementation detail this way (of > course, it will still add valuable user-visible features like > introspection and documentation). > > Apart from making things more future proof, this also immediately adds > a way to do non-scalar properties on the command line. nvme could have > used list support recently, and the lack of it in -device led to some > rather unnatural solution in the first version (doing the relationship > between a device and objects backwards) and loss of features in the > following. With this series, using a list as a device property should be > possible without any weird tricks. > > Unfortunately, even QMP device_add goes through QemuOpts before this > series, which destroys any type safety QOM provides and also can't > support non-scalar properties. This is a bug, but it turns out that > libvirt actually relies on it and passes only strings for everything. > So this series still leaves device_add alone until libvirt is fixed. Reviewed-by: Michael S. Tsirkin <mst(a)redhat.com&gt; I assume you are merging this?