Dynamic Root of Trust for Measurement (DRTM) mechanisms can be initiated, not by CPU-manufacturer-specific instructions, but by the execution of code in System Management Mode (SMM) that can modify the values stored in specific Platform Configuration Registers (PCRs) of a Trusted Platform Module (TPM). The SMM code can be verified prior to execution and it can be trusted based on the secure mechanisms used to update such code. The SMM code can restore a known, trusted state of the computing device and can initiate the measuring of subsequently executed code. In such a manner the Trusted Computing Base (TCB) can be limited.