Re: [PATCH v9 2/8] mm,memory_hotplug: Relax fully spanned sections check

From: Oscar Salvador
Date: Wed Apr 21 2021 - 03:37:50 EST


On Tue, Apr 20, 2021 at 11:40:50AM +0200, Michal Hocko wrote:
> On Fri 16-04-21 13:24:05, Oscar Salvador wrote:
> > When using self-hosted vmemmap pages, the number of pages passed to
> > {online,offline}_pages might not fully span sections, but they always
> > fully span pageblocks.
> > Relax the check account for that case.
>
> It would be good to call those out explicitly. It would be also
> great to explain why pageblock_nr_pages is an actual constrain. There
> shouldn't be any real reason for that except for "we want online_pages
> to operate on whole memblocks and memmap_on_memory will poke
> pageblock_nr_pages aligned holes in the beginning which is a special
> case we want to allow."

Sounds good.

>
> > Signed-off-by: Oscar Salvador <osalvador@xxxxxxx>
> > Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>
>
> With the changelog extended and the comment clarification (se below)
> feel free to add

Ok, thanks for the suggestion Michal.

> Acked-by: Michal Hocko <mhocko@xxxxxxxx>

--
Oscar Salvador
SUSE L3