On Wed, Mar 19, 2025 at 05:09:06PM +0800, Gao Xiang wrote: > The minimum map unit is page size instead of variable-size folio. > > For many cases, vmap (to combine many partial folios) is useful > (instead of split all folios to order-0 folios in advance) but > I agree page array may be inefficient. > > So I don't think another folio vmap() version is better overall > anyway. Then just reject the mappings for now. vmap/vm_map_ram isn't really intended for mapping totally arbitrary scattered memory anyway. As mentioned before udmabuf also has a grave bug in the dma mapping part, so just marking it broken would be another very sensible option.
