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Anything that does >> folio_rmap_remove_ptes can cause the folio to be deferred split if it gets partially >> unmapped. > > Right, but it's easy to exclude zone-device folios here. So the real question is: do you want to deal with deferred splits or not? > > If not, then just disable it right from the start. > I agree, I was trying to avoid special casing device private folios unless needed to the extent possible Balbir