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Recent research has exposed a number of security issues related to the use of FPGAs in embedded system and cloud computing environments. Circuits that deliberately waste power can be carefully crafted by a malicious cloud FPGA user and deployed to cause denial-of-service and fault injection attacks. The main defense strategy used by FPGA cloud services involves checking user-submitted designs for circuit structures that are known to aggressively consume power. Unfortunately, this approach is limited by an attacker’s ability to conceive new designs that defeat existing checkers. In this work, our contributions are twofold. We evaluate a variety of circuit power wasting techniques that typically are not flagged by design rule checks imposed by FPGA cloud computing vendors. The efficiencies of five power wasting circuits, including our new design, are evaluated in terms of power consumed per logic resource. We then show that the source of voltage attacks based on power wasters can be identified. Our monitoring approach localizes the attack and suppresses the clock signal for the target region within 21 μs, which is fast enough to stop an attack before it causes a board reset. All experiments are performed using a state-of-the-art Intel Stratix 10 FPGA.
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High-Frequency Absorption-FIFO Pipelining for Stratix 10 HyperFlex
FPGAs commonly have significantly lower clock frequencies than many microprocessors and GPUs, due largely to propagation delays incurred by the reconfigurable interconnect. The Stratix 10 HyperFlex architecture reduces this problem by embedding numerous registers throughout the routing resources. However, such Hyper-Registers do not support back-pressure (i.e., pipeline stalls) that is commonly used in FPGA pipelines. In this paper, we present and evaluate pipeline transformations using absorption FIFOs, which avoid back-pressure limitations to enable numerous pipelines to benefit from HyperFlex, while also eliminating potentially expensive stall penalties incurred by existing techniques. We demonstrate that these transformations not only enable significant clock improvements on Stratix 10, but also for devices without HyperFlex, potentially making absorption FIFOs a better high-frequency strategy for any FPGA. In addition, we introduce optimizations that yield additional performance improvements by reducing stall penalties that can increase linearly with pipeline depth when restarting after a stall.
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- Award ID(s):
- 1738420
- PAR ID:
- 10073111
- Date Published:
- Journal Name:
- 26th IEEE International Symposium on Field-Programmable Custom Computing Machines (FCCM)
- Page Range / eLocation ID:
- 97 to 100
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/fccm.2018.00024
