And, as dhansen connected the dots, this should be the exact same protection scenario as UPM: https://lore.kernel.org/all/20221025151344.3784230-1-chao.p.peng@xxxxxxxxxxxxxxx so you should be able to mark them inaccessible the same way and you won't need any poisoning dance. And Michael has patches so you probably should talk to him... Thx. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette