In addition to protecting data written to filesystems by a private process, PRIVEXEC must also preserve the privacy
of virtual memory pages swapped to disk. This is different from existing approaches to swap encryption,
which use a single key to encrypt the entire swap device,and fail to meet our security requirements in the same way that fuldisk encryption also does not. Since swap space is shared
between processes with different user principals, PRIVEXEC encrypts each private process memory page that is swapped
to disk with the PEK of the corresponding process as in the filesystem case, and thus imposes a per-application
partitioning of the system swap