Re: [Qemu-devel] [PATCH] hw/arm/bcm283x: Fix crash with device_add bcm2837 on unsupported machines

[Peter Maydell <peter.maydell@linaro.org>]

On 12 July 2018 at 17:16, Markus Armbruster <armbru@redhat.com> wrote:
> Thomas Huth <thuth@redhat.com> writes:
>
>> On 12.07.2018 14:06, Markus Armbruster wrote:
>>> Peter Maydell <peter.maydell@linaro.org> writes:
>>>
>>>> On 11 July 2018 at 17:12, Eduardo Habkost <ehabkost@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.
>>
>> Well, maybe I should then not suggest to add a hmp("info qtree") below
>> the hmp("info qom-tree") in test_one_device() of
>> tests/device-introspect-test.c ... otherwise we'll be quite busy in the
>> next weeks...
>
> If we can't fix these bugs in time, we can bring back
> cannot_destroy_with_object_finalize_yet, as Eduardo mentioned upthread.
> Would be sad, but sad beats crash.

...but are they actually interesting crashes? Nobody is ever
going to actually start emulation of an integratorcp machine and
then try to add a bcm2837 device via the QMP interface, except
if they're deliberately doing exhaustive testing. They're bugs,
sure, but they're not bugs I can ever see any real user possibly
tripping over, so we don't necessarily need to go to any
particular lengths to fix them for 3.0 if that's painful.

thanks
-- PMM