Re: [PATCH v2 0/2] mm: Memory offlining + page isolation cleanups

From: David Hildenbrand
Date: Tue Oct 22 2019 - 02:52:48 EST

On 21.10.19 19:23, David Hildenbrand wrote:
Two cleanups that popped up while working on (and discussing) virtio-mem:

Tested with DIMMs on x86.

As discussed with michal in v1, I'll soon look into removing the use
of PG_reserved during memory onlining completely - most probably
disallowing to offline memory blocks with holes, cleaning up the
onlining+offlining code.

BTW, I remember that ZONE_DEVICE pages are still required to be set PG_reserved. That has to be sorted out first. I remember that somebody was working on it a while ago but didn't hear about that again. Will look into that as well - should be as easy as adding a zone check (if there isn't a pfn_to_online_page() check already). But of course, there might be special cases ....



David / dhildenb