Abstract
When user and kernel mode processes are scheduled to run simultaneously on the same physical processor core via simultaneous multithreading, processor vulnerabilities can result in sensitive data restricted to kernel-mode processes being leaked to user-mode processes. While disabling simultaneous multithreading or use of a scheduler that determines sequence of execution can prevent such leakage, these changes degrade processor performance. This disclosure describes the use of per-CPU counters to track when each physical core of a processor begins and ends the execution of a program thread running in the kernel mode. Upon detection of such a thread, the core is identified as being in an unsafe state and all user-mode tasks are halted using an inter-processor interrupt.
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Recommended Citation
Fernandes, Joel Agnel, "Use of Per-CPU Counters to Protect Kernel-Mode Processes on a Multicore Processor", Technical Disclosure Commons, (December 01, 2020)
https://www.tdcommons.org/dpubs_series/3843