Peter Maydell <peter.mayd...@linaro.org> writes: > On 11 July 2018 at 17:12, Eduardo Habkost <ehabk...@redhat.com> wrote: >> On Wed, Jul 11, 2018 at 09:21:48AM +0200, Thomas Huth wrote: >>> Hm, ok, so how to continue here now? Shall we at least mark the >>> bcm2836/7 devices with user_creatable=false, so that users can not crash >>> their QEMU so easily with device_add? The problem with introspection via >>> device-list-properties would still continue to exist, but I think that's >>> less likely used in practice... otherwise we could still move the >>> qdev_set_parent_bus() calls to the realize() function instead, and just >>> add a big fat FIXME comment in front of the code block, so that we >>> remember to clean that up one day... >> >> Crashing device-list-properties should be a blocker bug, IMO.
Seconded. >> Moving to realize is not the best solution, but I would prefer to >> do that in 3.0 instead of leaving the device-list-properties >> crash unfixed. > > I would like to see the crash fixed too. But I'd like to > see it fixed: > (a) by having clear documentation about how the QOM > system works, what you should do in init and what you > should do in realize, when and why you need to manually > parent objects, etc > (b) as far as possible making our APIs for doing this > easy to use correctly and difficult to use wrongly. At > the moment we have APIs that are far too easy to misuse, > which means we will continue to get bugs like this and spend > a lot of time on one-off fixes for them. > > In particular I don't understand why we need to manually > parent these objects at all. I want both (a) and (b) as badly as anyone, but we should not hold any particular crash bug hostage to get them.
