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Date:   Tue, 16 Feb 2021 09:21:01 +0100
From:   Michal Hocko <mhocko@suse.com>
To:     David Hildenbrand <david@redhat.com>
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Subject: Re: [External] Re: [PATCH v15 4/8] mm: hugetlb: alloc the vmemmap
 pages associated with each HugeTLB page
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On Tue 16-02-21 09:13:09, David Hildenbrand wrote:
> On 15.02.21 20:02, Michal Hocko wrote:
> > Would it be feasible to reused parts of the freed page in
> > the worst case?
> 
> As already discussed, this is only possible when the huge page does not
> reside on ZONE_MOVABLE/CMA.

Right. But usually this is not the case so it would be at least
something.

> In addition, we can no longer form a huge page at that memory location ever.

Yes, that's why I am saying in the worst case. E.g. when dissolving is
really necessary like in hwpoison case.

Maybe we are really far from needing something like that. I just wanted
to mention this option and I was not aware this has been discussed
previously.
-- 
Michal Hocko
SUSE Labs