On Fri 13-04-18 15:16:26, David Hildenbrand wrote: > online_pages()/offline_pages() theoretically allows us to work on > sub-section sizes. This is especially relevant in the context of > virtualization. It e.g. allows us to add/remove memory to Linux in a VM in > 4MB chunks. Well, theoretically possible but this would require a lot of auditing because the hotplug and per section assumption is quite a spread one. > While the whole section is marked as online/offline, we have to know > the state of each page. E.g. to not read memory that is not online > during kexec() or to properly mark a section as offline as soon as all > contained pages are offline. But you cannot use a page flag for that, I am afraid. Page flags are extremely scarce resource. I haven't looked at the rest of the series but _if_ we have a bit spare which I am not really sure about then you should prove there are no other ways around this. > Signed-off-by: David Hildenbrand <david@xxxxxxxxxx> -- Michal Hocko SUSE Labs
