[PATCH v9 04/12] x86, mpx: add MPX to disaabled features

From: Qiaowei Ren
Date: Sun Oct 12 2014 - 00:54:48 EST


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.

This patch must be applied after another Dave's commit:
381aa07a9b4e1f82969203e9e4863da2a157781d

Signed-off-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Signed-off-by: Qiaowei Ren <qiaowei.ren@xxxxxxxxx>
---
arch/x86/include/asm/disabled-features.h | 8 +++++++-
1 files changed, 7 insertions(+), 1 deletions(-)

diff --git a/arch/x86/include/asm/disabled-features.h b/arch/x86/include/asm/disabled-features.h
index 97534a7..f226df0 100644
--- a/arch/x86/include/asm/disabled-features.h
+++ b/arch/x86/include/asm/disabled-features.h
@@ -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 */
--
1.7.1

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