A data processing system supports remeasurement of a virtual machine monitor (VMM). In one example process, the VMM may obtain a secret value from a trusted platform module (TPM) of the processing system. The VMM may provide the secret value from the VMM to a measurement agent executing in system management mode (SMM) of the processing system. The measurement agent may be a system management interrupt (SMI) transfer monitor (STM) that can create virtual machines to execute in SMM, for example. However, the VMM may verify the measurement agent before providing the secret value to the measurement agent. The measurement agent may generate a remeasurement value for the VMM, use the secret value that was obtained from the TPM to certify the remeasurement value, and communicate the remeasurement value to a requesting program, via the VMM. Other embodiments are described and claimed.