1. In a computer system comprising a host hardware platform, virtualization software running on the host hardware platform, and a virtual machine running on the virtualization software, a method for tracking data correspondences which comprises: monitoring one or more data movement operations of the computer system; and storing information regarding the one or more data movement operations in a data correspondence structure, which information provides a correspondence between data before one of the one or more data movement operations and data after the one of the one or more data movement operations.