Re: [Qemu-devel] [PATCH 21/27] pc: add memory hotplug 440fx machine

["Andreas Färber" <afaerber@suse.de>]

Am 21.11.2013 15:34, schrieb Igor Mammedov:
> On Thu, 21 Nov 2013 15:13:12 +0100
> Andreas Färber <afaerber@suse.de> wrote:
>> Am 21.11.2013 06:48, schrieb Li Guang:
>>> Why not give the memory that not be hot-added a chance to be placed on
>>> one memory slot?
>>
>> Seconded, I believe I requested that on the previous version already.
> Because current initial memory allocation is a mess and this already
> large series would become even more large and intrusive, so far series
> it relatively not intrusive and self contained.
> 
> I believe re-factoring of initial memory to use Dimm devices should be
> done later on top of infrastructure this series provides.

My problem with that is that that would be a semantically incompatible
modeling change. With your series we might have /machine/dimm.0/child[0]
be the first hot-plugged memory and once such a refactoring is done,
child[0] silently becomes -m and child[1] is the hot-added one.

So if we know that we want/need to change the infrastructure, why not
add a single patch (?) to allocate one additional object on the bus now?
Unless we actually write the code, we won't know whether there are some
incorrect hot-plug assumptions in the dimm code.

Andreas

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