Re: [Qemu-devel] in a device or CPU instance init/realize, can I rely on something having the BQL or equivalent?

[Peter Maydell]

On 7 December 2017 at 17:13, Peter Maydell <address@hidden> wrote:
> On 7 December 2017 at 17:07, Eduardo Habkost <address@hidden> wrote:
>> On Thu, Dec 07, 2017 at 04:53:59PM +0000, Peter Maydell wrote:
>>> On 7 December 2017 at 16:48, Igor Mammedov <address@hidden> wrote:
>>> > On Thu, 7 Dec 2017 16:05:50 +0000
>>> > Peter Maydell <address@hidden> wrote:
>>> >
>>> >> Hi; I'm currently writing '-cpu max' support for ARM. For that I'd
>>> >> like to be able to do the "probe host kernel for its supported feature
>>> >> set" in the CPU object's instance-init function, but I'd like to do
>>
>> I don't think instance_init is appropriate for that, as
>> object_free(object_new(t)) must be always safe to call and free
>> of side-effects for all types.  Wouldn't it work if you do that
>> on realize?
>
> I think we need the information before realize, but I'll double
> check.

We do need the information before realize, because the probe
is what tells us what feature bits we need to set, and the
ARM instance_post_init hook needs to look at those to determine
eg which other feature bits to set and which QOM properties to
expose as a result, and all that has to happen at init time,
not realize time.

thanks
-- PMM