Macroeconomics

Speculation

Speculative execution

Embedded system

Computer security

Speculative multithreading

Operating system

Economics

Parallel computing

Computer science

Side channel attack

Multithreading

Software

Database

Commit

Microarchitecture

Cryptography

Thread (computing)

Speculative attacks, such as Spectre and Meltdown, target speculative execution to access privileged data and leak it through a side-channel. In this paper, we introduce (SafeSpec), a new model for supporting speculation in a way that is immune to the side-channel leakage by storing side effects of speculative instructions in separate structures until they commit. Additionally, we address the possibility of a covert channel from speculative instructions to committed instructions before these instructions are committed. We develop a cycle accurate model of modified design of an x86-64 processor and show that the performance impact is negligible.

SafeSpec