On Wed, 14 Jul 2021 20:35:28 +0100 Joao Martins [off-list ref] wrote:

This series, attempts at minimizing 'struct page' overhead by
pursuing a similar approach as Muchun Song series "Free some vmemmap
pages of hugetlb page"[0] but applied to devmap/ZONE_DEVICE which is now
in mmotm. 

[0] https://lore.kernel.org/linux-mm/20210308102807.59745-1-songmuchun@bytedance.com/ (local)

[0] is now in mainline.

This patch series looks like it'll clash significantly with the folio
work and it is pretty thinly reviewed, so I think I'll take a pass for
now.  Matthew, thoughts?