Denial-of-Service Attacks on Shared Resources in Intel’s Integrated CPU-GPU Platforms

In this paper, we study the effectiveness of denial-of-service (DoS) attacks on Intel’s heterogeneous multicore system-on-chips with integrated GPU (iGPU) in which the last level cache (LLC) and the main memory subsystem are shared between the multicore CPU and the iGPU. Using two Intel processors with iGPU, we evaluate four different DoS attacks, three CPU based and one iGPU based, and show they can induce very high degree of shared resource contention and thus dramatically slowdown the victim’s execution time. We further evaluate the effectiveness of Intel’s recent hardware based shared resource isolation mechanisms, namely Intel Cache Allocation Technology (CAT) and Graphics Technology Class of Service (GT COS), which provide shared LLC partitioning capability for the CPU cores and the iGPU, respectively, in defending against these DoS attacks. Using both synthetic and real-world benchmarks, we find that hardware based LLC partitioning mechanisms does provide spatial LLC space isolation but does not necessarily provide temporal isolation.