From: Dave Hansen <dave.han...@linux.intel.com>

This allows us to use cpu_feature_enabled(X86_FEATURE_MPX) as
both a runtime and compile-time check.

When CONFIG_X86_INTEL_MPX is disabled,
cpu_feature_enabled(X86_FEATURE_MPX) will evaluate at
compile-time to 0. If CONFIG_X86_INTEL_MPX=y, then the cpuid
flag will be checked at runtime.

Signed-off-by: Dave Hansen <dave.han...@linux.intel.com>
Signed-off-by: Qiaowei Ren <qiaowei....@intel.com>
---

 b/arch/x86/include/asm/disabled-features.h |    8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff -puN 
arch/x86/include/asm/disabled-features.h~mpx-v11-add-MPX-to-disaabled-features 
arch/x86/include/asm/disabled-features.h
--- 
a/arch/x86/include/asm/disabled-features.h~mpx-v11-add-MPX-to-disaabled-features
    2014-11-14 07:06:22.297610243 -0800
+++ b/arch/x86/include/asm/disabled-features.h  2014-11-14 07:06:22.300610378 
-0800
@@ -10,6 +10,12 @@
  * cpu_feature_enabled().
  */
 
+#ifdef CONFIG_X86_INTEL_MPX
+# define DISABLE_MPX   0
+#else
+# define DISABLE_MPX   (1<<(X86_FEATURE_MPX & 31))
+#endif
+
 #ifdef CONFIG_X86_64
 # define DISABLE_VME           (1<<(X86_FEATURE_VME & 31))
 # define DISABLE_K6_MTRR       (1<<(X86_FEATURE_K6_MTRR & 31))
@@ -34,6 +40,6 @@
 #define DISABLED_MASK6 0
 #define DISABLED_MASK7 0
 #define DISABLED_MASK8 0
-#define DISABLED_MASK9 0
+#define DISABLED_MASK9 (DISABLE_MPX)
 
 #endif /* _ASM_X86_DISABLED_FEATURES_H */
_
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