Re: [Qemu-devel] [RESEND PATCH v8 2/4] hw: add a wrapper for registering reset handler

[Andreas Färber]

Am 25.06.2015 um 19:00 schrieb Paolo Bonzini:
> On 25/06/2015 04:17, Zhu Guihua wrote:
>> Add a wrapper to specify reset order when registering reset handler,
>> instead of non-obvious initiazation code ordering.
>>
>> Signed-off-by: Zhu Guihua <address@hidden>
> 
> I'm sorry, this is not really acceptable.  The initialization code
> ordering is good because it should be okay to run reset handlers in the
> same order as code is run.  If there are dependencies between reset
> handlers, a random integer is not a maintainable way to maintain them.
> 
> Instead, you should have a single reset handler that calls the reset
> handlers in the right order; for example a qdev bus such as icc_bus
> always resets children before parents.
> 
> Are you sure that you want to remove the icc_bus?... What are you
> gaining exactly by doing so?

>From my view we would be gaining by making the APIC an integral part
(child<>) of the CPU in a follow-up step (there's a TODO to make things
link<>s).

But either way the CPU's existing reset handler should be able to handle
CPU/APIC interdependencies just fine, somehow. Which is what Eduardo
said on v6 and v7. (Another alternative he raised was a machine init
notifier, but I see no code for that after its mention on v7?)

Cheers,
Andreas

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