[RFC PATCH 1/7] x86/cpufeatures: add X86_FEATURE_SCI

[Mike Rapoport]

The X86_FEATURE_SCI will be set when system call isolation is enabled.

Signed-off-by: Mike Rapoport <rppt at linux.ibm.com>
---
 arch/x86/include/asm/cpufeatures.h       | 1 +
 arch/x86/include/asm/disabled-features.h | 8 +++++++-
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
index 6d61225..a01c6dd 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -221,6 +221,7 @@
 #define X86_FEATURE_ZEN			( 7*32+28) /* "" CPU is AMD family 0x17 (Zen) */
 #define X86_FEATURE_L1TF_PTEINV		( 7*32+29) /* "" L1TF workaround PTE inversion */
 #define X86_FEATURE_IBRS_ENHANCED	( 7*32+30) /* Enhanced IBRS */
+#define X86_FEATURE_SCI			( 7*32+31) /* "" System call isolation */
 
 /* Virtualization flags: Linux defined, word 8 */
 #define X86_FEATURE_TPR_SHADOW		( 8*32+ 0) /* Intel TPR Shadow */
diff --git a/arch/x86/include/asm/disabled-features.h b/arch/x86/include/asm/disabled-features.h
index a5ea841..79947f0 100644
--- a/arch/x86/include/asm/disabled-features.h
+++ b/arch/x86/include/asm/disabled-features.h
@@ -62,6 +62,12 @@
 # define DISABLE_PTI		(1 << (X86_FEATURE_PTI & 31))
 #endif
 
+#ifdef CONFIG_SYSCALL_ISOLATION
+# define DISABLE_SCI		0
+#else
+# define DISABLE_SCI		(1 << (X86_FEATURE_SCI & 31))
+#endif
+
 /*
  * Make sure to add features to the correct mask
  */
@@ -72,7 +78,7 @@
 #define DISABLED_MASK4	(DISABLE_PCID)
 #define DISABLED_MASK5	0
 #define DISABLED_MASK6	0
-#define DISABLED_MASK7	(DISABLE_PTI)
+#define DISABLED_MASK7	(DISABLE_PTI|DISABLE_SCI)
 #define DISABLED_MASK8	0
 #define DISABLED_MASK9	(DISABLE_MPX|DISABLE_SMAP)
 #define DISABLED_MASK10	0
-- 
2.7.4