Re: [GIT pull] x86 mpx support for 3.19

From: Pavel Machek
Date: Fri Dec 12 2014 - 07:30:54 EST



> +config X86_INTEL_MPX
> + prompt "Intel MPX (Memory Protection Extensions)"
> + def_bool y

bool?

> + 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.
> +
> + This option enables running applications which are
> + instrumented or otherwise use MPX. It does not use MPX
> + itself inside the kernel or to protect the kernel
> + against bad memory references.
> +
> + Enabling this option will make the kernel larger:
> + ~8k of kernel text and 36 bytes of data on a 64-bit
> + defconfig. It adds a long to the 'mm_struct' which
> + will increase the kernel memory overhead of each
> + process and adds some branches to paths used during
> + exec() and munmap().

Should you explain what kind of CPUs support it? Basically "the kind
you don't have, yet"?

> + If unsure, say Y.

Disagreed here. Right now, N is right response to anyone but Intel.
Pavel
--
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