Hi,
sorry for the delay. On Tue, Feb 19, 2013 at 07:39:40PM -0300, Erlon Cruz wrote:
I think the DimmDevice is generic enough but I am open to other suggestions.
A related issue is that the patchseries uses a DimmBus to hot-add and hot-remove DimmDevice. Another approach that has been suggested is to use links<> between DimmDevices and the dram controller device (piix4 or mch for pc and q35-pc machines respectively). This would be more similar to the CPUState/qom patches - see Andreas Färber's earlier reply to this thread.
I think we should get some consensus from the community/maintainers before we continue to integrate.
I haven't updated the series for a while, but I can rework if there is a more clear direction for the community.
Another open issue is reference counting of memoryregions in qemu memory model. In order to make memory hot-remove operations safe, we need to remove a memoryregion after all users (e.g. both guest and block layer) have stopped using it, see discussion at http://lists.gnu.org/archive/html/qemu-devel/2012-10/msg03986.html. There was a relevant ibm patchset https://lists.gnu.org/archive/html/qemu-devel/2012-11/msg02697.html but it was not merged.
The non-hotpluggable initial memory (-m) is currently not modelled at all as a DimmDevice. We may want to model it though.
thanks, - Vasilis
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Vasilis Liaskovitis