TDX Module Trusted Fault Buffer Queues for Confidential Paging

The system is segmented into trusted and untrusted components. The TDX module and fault buffer queues are placed within the trusted computing base, while the virtual machine manager and host software stack remain outside. This segmentation allows the untrusted components to manage virtual machines without compromising the security of paging operations, as the trusted components enforce security policies and protect sensitive data structures.

The TDX module acts as an intermediary between the untrusted virtual machine manager and the trusted fault buffer queues. It receives paging requests from the virtual machine manager, validates them against security policies, and executes paging operations within the trusted computing base. This intermediary role allows flexible management while maintaining security, as the TDX module translates untrusted management operations into secure trusted operations.

The critical security functions for on-demand paging are extracted and placed within the trusted computing base in the form of dedicated hardware registers and the TDX module. These extracted components handle only the essential security-critical operations (fault buffer management, page fault handling), while leaving the complex virtual machine management functions to the untrusted host software. This extraction minimizes the complexity within the trusted base while maximizing security.

The TDX module and associated hardware registers are designed to handle multiple paging-related functions within the trusted computing base, including fault buffer queue management, page fault interception, address translation validation, and data movement coordination. By making these trusted components multi-functional, the patent reduces the need for additional separate security mechanisms, thereby limiting the increase in complexity while maintaining comprehensive security coverage.