Add CPU feature flags for Control-flow Enforcement Technology (CET).

CPUID.(EAX=7,ECX=0):ECX[bit 7] Shadow stack
CPUID.(EAX=7,ECX=0):EDX[bit 20] Indirect Branch Tracking

Signed-off-by: Yu-cheng Yu <yu-cheng...@intel.com>
---
 arch/x86/include/asm/cpufeatures.h       |  2 ++
 arch/x86/include/asm/disabled-features.h | 12 ++++++++++--
 arch/x86/kernel/cpu/cpuid-deps.c         |  2 ++
 3 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/cpufeatures.h 
b/arch/x86/include/asm/cpufeatures.h
index 84b887825f12..292fe87b26b3 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -345,6 +345,7 @@
 #define X86_FEATURE_OSPKE              (16*32+ 4) /* OS Protection Keys Enable 
*/
 #define X86_FEATURE_WAITPKG            (16*32+ 5) /* UMONITOR/UMWAIT/TPAUSE 
Instructions */
 #define X86_FEATURE_AVX512_VBMI2       (16*32+ 6) /* Additional AVX512 Vector 
Bit Manipulation Instructions */
+#define X86_FEATURE_SHSTK              (16*32+ 7) /* Shadow Stack */
 #define X86_FEATURE_GFNI               (16*32+ 8) /* Galois Field New 
Instructions */
 #define X86_FEATURE_VAES               (16*32+ 9) /* Vector AES */
 #define X86_FEATURE_VPCLMULQDQ         (16*32+10) /* Carry-Less Multiplication 
Double Quadword */
@@ -377,6 +378,7 @@
 #define X86_FEATURE_TSXLDTRK           (18*32+16) /* TSX Suspend Load Address 
Tracking */
 #define X86_FEATURE_PCONFIG            (18*32+18) /* Intel PCONFIG */
 #define X86_FEATURE_ARCH_LBR           (18*32+19) /* Intel ARCH LBR */
+#define X86_FEATURE_IBT                        (18*32+20) /* Indirect Branch 
Tracking */
 #define X86_FEATURE_AVX512_FP16                (18*32+23) /* AVX512 FP16 */
 #define X86_FEATURE_SPEC_CTRL          (18*32+26) /* "" Speculation Control 
(IBRS + IBPB) */
 #define X86_FEATURE_INTEL_STIBP                (18*32+27) /* "" Single Thread 
Indirect Branch Predictors */
diff --git a/arch/x86/include/asm/disabled-features.h 
b/arch/x86/include/asm/disabled-features.h
index 7947cb1782da..a66e7f34b788 100644
--- a/arch/x86/include/asm/disabled-features.h
+++ b/arch/x86/include/asm/disabled-features.h
@@ -68,6 +68,14 @@
 # define DISABLE_SGX   (1 << (X86_FEATURE_SGX & 31))
 #endif
 
+#ifdef CONFIG_X86_CET
+#define DISABLE_SHSTK  0
+#define DISABLE_IBT    0
+#else
+#define DISABLE_SHSTK  (1 << (X86_FEATURE_SHSTK & 31))
+#define DISABLE_IBT    (1 << (X86_FEATURE_IBT & 31))
+#endif
+
 /*
  * Make sure to add features to the correct mask
  */
@@ -88,9 +96,9 @@
 #define DISABLED_MASK14        0
 #define DISABLED_MASK15        0
 #define DISABLED_MASK16        
(DISABLE_PKU|DISABLE_OSPKE|DISABLE_LA57|DISABLE_UMIP| \
-                        DISABLE_ENQCMD)
+                        DISABLE_ENQCMD|DISABLE_SHSTK)
 #define DISABLED_MASK17        0
-#define DISABLED_MASK18        0
+#define DISABLED_MASK18        (DISABLE_IBT)
 #define DISABLED_MASK_CHECK BUILD_BUG_ON_ZERO(NCAPINTS != 19)
 
 #endif /* _ASM_X86_DISABLED_FEATURES_H */
diff --git a/arch/x86/kernel/cpu/cpuid-deps.c b/arch/x86/kernel/cpu/cpuid-deps.c
index 42af31b64c2c..52d9a682a0e6 100644
--- a/arch/x86/kernel/cpu/cpuid-deps.c
+++ b/arch/x86/kernel/cpu/cpuid-deps.c
@@ -72,6 +72,8 @@ static const struct cpuid_dep cpuid_deps[] = {
        { X86_FEATURE_AVX512_FP16,              X86_FEATURE_AVX512BW  },
        { X86_FEATURE_ENQCMD,                   X86_FEATURE_XSAVES    },
        { X86_FEATURE_PER_THREAD_MBA,           X86_FEATURE_MBA       },
+       { X86_FEATURE_SHSTK,                    X86_FEATURE_XSAVES    },
+       { X86_FEATURE_IBT,                      X86_FEATURE_XSAVES    },
        {}
 };
 
-- 
2.21.0

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