On Thu, Feb 11, 2021 at 11:02:07AM +0100, David Hildenbrand wrote: > > Another thought regarding "doesn't have _any_ backing storage" > > What are the right semantics when it comes to memory accounting/commit? > > As secretmem does not have > a) any backing storage > b) cannot go to swap > > The MAP_NORESERVE vs. !MAP_NORESERVE handling gets a little unclear. Why > "reserve swap space" if the allocations cannot ever go to swap? Sure, we > want to "reserve physical memory", but in contrast to other users that can > go to swap. > > Of course, this is only relevant for MAP_PRIVATE secretmem mappings. Other > MAP_SHARED assumes there is no need for reserving swap space as it can just > go to the backing storage. (yeah, tmpfs/shmem is weird in that regard as > well, but again, it's a bit different) In that sense seceremem is as weird as tmpfs and it only allows MAP_SHARED. -- Sincerely yours, Mike.
