Re: memory offline infinite loop after soft offline

From: Michal Hocko
Date: Fri Oct 18 2019 - 04:55:32 EST


On Fri 18-10-19 10:38:21, David Hildenbrand wrote:
> On 18.10.19 10:24, Michal Hocko wrote:
> > On Fri 18-10-19 10:13:36, David Hildenbrand wrote:
> > [...]
> > > However, if the compound page spans multiple pageblocks
> >
> > Although hugetlb pages spanning pageblocks are possible this shouldn't
> > matter in__test_page_isolated_in_pageblock because this function doesn't
> > really operate on pageblocks as the name suggests. It is simply
> > traversing all valid RAM ranges (see walk_system_ram_range).
>
> As long as the hugepages don't span memory blocks/sections, you are right. I
> have no experience with gigantic pages in this regard.

They can clearly span sections (1GB is larger than 128MB). Why do you
think it matters actually? walk_system_ram_range walks RAM ranges and no
allocation should span holes in RAM right?
--
Michal Hocko
SUSE Labs