On 12/10/2014 11:05 AM, Linus Torvalds wrote:
> On Tue, Dec 9, 2014 at 6:08 AM, Thomas Gleixner <tglx@linutronix.de> wrote:
> Why would I want to enable this in my kernel when there are no actual
> CPU's out yet that support it? And even when there are, why would I do
> it if the CPU I have doesn't support it?

There's no good reason to enable it except for testing (compile, or
making sure we didn't screw up the #BR code for CPUs without MPX).

Patch is attached to add the following:

> config X86_INTEL_MPX
>         prompt "Intel MPX (Memory Protection Extensions)" if EXPERT
>         def_bool y
>         depends on CPU_SUP_INTEL
>         ---help---
>           MPX provides hardware features that can be used in
>           conjunction with compiler-instrumented code to check
>           memory references.  It is designed to detect buffer
>           overflow or underflow bugs.
> 
>           Enabling this option will make the kernel larger and
>           slightly increase the size of some data structures.
> 
>           If unsure, say Y.