[PATCH 23/31] x86, pkeys: add Kconfig prompt to existing config option

[Dave Hansen]

From: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>

I don't have a strong opinion on whether we need this or not.
Protection Keys has relatively little code associated with it,
and it is not a heavyweight feature to keep enabled.  However,
I can imagine that folks would still appreciate being able to
disable it.

Here's the option if folks want it.

Signed-off-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Reviewed-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
---

 b/arch/x86/Kconfig |   10 ++++++++++
 1 file changed, 10 insertions(+)

diff -puN arch/x86/Kconfig~pkeys-40-kconfig-prompt arch/x86/Kconfig
--- a/arch/x86/Kconfig~pkeys-40-kconfig-prompt	2016-01-28 15:52:26.863702069 -0800
+++ b/arch/x86/Kconfig	2016-01-28 15:52:26.867702253 -0800
@@ -1716,8 +1716,18 @@ config X86_INTEL_MPX
 	  If unsure, say N.
 
 config X86_INTEL_MEMORY_PROTECTION_KEYS
+	prompt "Intel Memory Protection Keys"
 	def_bool y
+	# Note: only available in 64-bit mode
 	depends on CPU_SUP_INTEL && X86_64
+	---help---
+	  Memory Protection Keys provides a mechanism for enforcing
+	  page-based protections, but without requiring modification of the
+	  page tables when an application changes protection domains.
+
+	  For details, see Documentation/x86/protection-keys.txt
+
+	  If unsure, say y.
 
 config EFI
 	bool "EFI runtime service support"
_