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instead, the= caller > * will receive an -EAGAIN. > * > - * 4) @new_order > 1, usually. Order-1 is not supported for anon or swap= cache > - * folios: anon folios need subpage 2 for _deferred_list, which order= -1 > - * folios lack, and a swapcache folio may become anon once faulted in= . > - * File-backed order-1 folios are supported, since they do not use > - * _deferred_list. > + * 4) @new_order !=3D 1 for anon or swapcache. Anon folios need subpage = 2 for We use head page + tail pages instead of subpages, so the sentence could be Anon folios stores _deferred_list in second tail page, which order-1 folios lack, ... > + * _deferred_list, which order-1 folios lack, and a swapcache folio m= ay > + * become anon once faulted in. File-backed order-1 folios are suppor= ted, > + * since they do not use _deferred_list. > * > * After splitting, the caller's folio reference will be transferred to = @page, > * resulting in a raised refcount of @page after this call. The other pa= ges may > @@ -4432,7 +4431,7 @@ int folio_split_unmapped(struct folio *folio, unsig= ned int new_order) > * with the folio. Splitting to order 0 is compatible with all folios. > */ > int __split_huge_page_to_list_to_order(struct page *page, struct list_he= ad *list, > - unsigned int new_order) > + unsigned int new_order) > { > struct folio *folio =3D page_folio(page); > =20 Otherwise, LGTM. Reviewed-by: Zi Yan --=20 Best Regards, Yan, Zi