Re: [PATCH v1 0/3] mm/memory_hotplug: Export generic_online_page()

From: Michal Hocko
Date: Mon Sep 23 2019 - 08:07:26 EST


On Mon 23-09-19 13:34:18, David Hildenbrand wrote:
> On 23.09.19 13:15, Michal Hocko wrote:
[...]
> > I am wondering why those pages get onlined when they are, in fact,
> > supposed to be offline.
> >
>
> It's the current way of emulating sub-memory-block hotplug on top of the
> memory bock device API we have. Hyper-V and XEN have been using that for
> a long time.

Do they really have to use the existing block interface when they in
fact do not operate on the block granularity? Zone device memory already
acts on sub section/block boundaries.
--
Michal Hocko
SUSE Labs