Mike Yuan
5119063196
When employing MCL_FUTURE we don't actually want it to impose immediate population of malloc()-ed pages. Hence let's set MCL_ONFAULT everywhere. Additionally, specify MCL_CURRENT to ensure future memory allocations on already mapped pages are covered too. (Addresses https://github.com/systemd/systemd/pull/40319#discussion_r2693726196) Note that in shutdown the mlockall() is done to avoid keeping swap space busy, hence a dedicated call w/ MCL_CURRENT and w/o MCL_ONFAULT is made.