Gutting Out Intel MPX Support To Be Finished Up In The Linux 5.6 Kernel

Written by Michael Larabel in Intel on 23 January 2020 at 07:38 AM EST. Add A Comment
INTEL
Last year Linux kernel developers began removing support for Intel's Memory Protection Extensions (MPX) and that looks like it will be finished up in the forthcoming Linux 5.6 cycle.

The Linux support for Intel MPX has already been pretty much dead since the GCC 9 compiler dropped support for MPX. Kernel developers following that began working to remove MPX from the kernel over not having the compiler support, MPX not being widely used, and also not much code movement on the kernel side. Memory Protection Extensions (MPX) was talked up years ago by Intel for allowing the checking of pointer references at run-time to avoid buffer overflows and other potential related vulnerabilities. But in reality it didn't become too popular with developers while AddressSanitizer and other compiler sanitizer infrastructure has become more used and without the need for special bits in the CPU. Intel themselves meanwhile have deprecated MPX and say the support won't be available on future CPUs, hence not being concerned much about the Linux support departing.


The Linux kernel has been losing MPX support since the end of 2018 while finally for the upcoming Linux 5.6 kernel the remnants of MPX in the kernel should be stripped out. Ahead of the Linux 5.6 merge window expected to begin next week is mpx-remove-202001 that clears out the rest of the lingering Memory Protection Extensions code.

Removing the rest of this MPX code lightens the kernel by over 1,600 lines.
Related News
About The Author
Michael Larabel

Michael Larabel is the principal author of Phoronix.com and founded the site in 2004 with a focus on enriching the Linux hardware experience. Michael has written more than 20,000 articles covering the state of Linux hardware support, Linux performance, graphics drivers, and other topics. Michael is also the lead developer of the Phoronix Test Suite, Phoromatic, and OpenBenchmarking.org automated benchmarking software. He can be followed via Twitter, LinkedIn, or contacted via MichaelLarabel.com.

Popular News This Week