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Date:   Mon, 26 Oct 2020 15:53:51 +0000
From:   Matthew Wilcox <willy@infradead.org>
To:     Muchun Song <songmuchun@bytedance.com>
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Subject: Re: [PATCH v2 00/19] Free some vmemmap pages of hugetlb page
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On Mon, Oct 26, 2020 at 10:50:55PM +0800, Muchun Song wrote:
> For tail pages, the value of compound_dtor is the same. So we can reuse

compound_dtor is only set on the first tail page.  compound_head is
what you mean here, I think.