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I would quite happily use that in iommufd as well. > > > > It solves some problems we have there with fork/exec/etc if the pages > > are not linked to a mm_struct. > > Afaiu any fd based approach should mean it'll never work with private > memories, while mm-based should be able to work on any kind. Is there a significant use case to open a memfd and then use MAP_PRIVATE? Why would anyone want to do that instead of just using normal mmap anonymous memory? Jason