On Mon 23-09-19 14:20:05, David Hildenbrand wrote: > On 23.09.19 14:07, Michal Hocko wrote: > > 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. > > > > Yes, we need memory blocks, especially for user space to properly online > them (as we discussed a while back, to decide on a zone) and for udev > events, to e.g., properly reload kexec when memory blocks get > added/removed/onlined/offlined. Just to make sure I really follow. We need a user interface to control where the memory gets onlined but it is the driver which determines which part of the block really gets onlined, right? -- Michal Hocko SUSE Labs
