On Mon, 28 Oct 2019, Kirill A. Shutemov wrote: > Setting a single 4k page non-present in the direct mapping will require > splitting 2M or 1G page we usually map direct mapping with. And it's one > way road. We don't have any mechanism to map the memory with huge page > again after the application has freed the page. > > It might be okay if all these pages cluster together, but I don't think we > have a way to achieve it easily. Set aside a special physical memory range for this and migrate the page to that physical memory range when MAP_EXCLUSIVE is specified? Maybe some processors also have hardware ranges that offer additional protection for stuff like that?
