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I decided to keep it simple for now and > check what are the alternatives, like moving away from memblock_reserve(), > adding a maple_tree or even something else. Okat, makes sense to me > > > + page->private = order; > > > > Can't just set the page order directly? Why use private? > > Setting the order means recreating the folio the way prep_compound_page() > does. I think it's better to postpone it until the folio is requested. This > way it might run after SMP is enabled. I see, that makes sense, but also it could stil use page->order.. > Besides, when we start allocating > folios separately from struct page, initializing it here would be a real > issue. Yes, but also we wouldn't have page->private to make it work.. Somehow anything we want to carry over would have to become encoded in the memdesc directly. I think this supports my remark someplace else that any user of this that wants to preserve per-page data should do it on its own somehow as an add-on-top? Jason