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It seems like an intended behavior because I saw MTE doc explicitly says PROT_MTE flags can't be cleared by mprotect(). But I don't see why mprotect() can't do it if I don't miss anything. So I'd like to know why it behaves in this way. unmap + mmap or mmap(MAP_FIXED) can do the trick, but it is not feasible for anonymous mapping because unamp will wipe all the data. Thanks, Yang