Commit-ID: dae0a10593007d049ea71601357ac41d4f247ee9
Gitweb: https://git.kernel.org/tip/dae0a10593007d049ea71601357ac41d4f247ee9
Author: Andy Lutomirski <luto@xxxxxxxxxx>
AuthorDate: Mon, 19 Nov 2018 14:45:27 -0800
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Tue, 20 Nov 2018 08:44:28 +0100
x86/cpufeatures, x86/fault: Mark SMAP as disabled when configured out
Add X86_FEATURE_SMAP to the disabled features mask as appropriate
and use cpu_feature_enabled() in the fault code. This lets us get
rid of a redundant IS_ENABLED(CONFIG_X86_SMAP).
Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Brian Gerst <brgerst@xxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: Denys Vlasenko <dvlasenk@xxxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Rik van Riel <riel@xxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Yu-cheng Yu <yu-cheng.yu@xxxxxxxxx>
Link: http://lkml.kernel.org/r/fe93332eded3d702f0b0b4cf83928d6830739ba3.1542667307.git.luto@xxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
arch/x86/include/asm/disabled-features.h | 8 +++++++-
arch/x86/mm/fault.c | 5 +----
2 files changed, 8 insertions(+), 5 deletions(-)
diff --git a/arch/x86/include/asm/disabled-features.h b/arch/x86/include/asm/disabled-features.h
index 33833d1909af..a5ea841cc6d2 100644
--- a/arch/x86/include/asm/disabled-features.h
+++ b/arch/x86/include/asm/disabled-features.h
@@ -16,6 +16,12 @@
# define DISABLE_MPX (1<<(X86_FEATURE_MPX & 31))
#endif
+#ifdef CONFIG_X86_SMAP
+# define DISABLE_SMAP 0
+#else
+# define DISABLE_SMAP (1<<(X86_FEATURE_SMAP & 31))
+#endif
+
#ifdef CONFIG_X86_INTEL_UMIP
# define DISABLE_UMIP 0
#else
@@ -68,7 +74,7 @@
#define DISABLED_MASK6 0
#define DISABLED_MASK7 (DISABLE_PTI)
#define DISABLED_MASK8 0
-#define DISABLED_MASK9 (DISABLE_MPX)
+#define DISABLED_MASK9 (DISABLE_MPX|DISABLE_SMAP)
#define DISABLED_MASK10 0
#define DISABLED_MASK11 0
#define DISABLED_MASK12 0
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index 8624cb7d8d65..39e39cd42097 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -1150,10 +1150,7 @@ static int fault_in_kernel_space(unsigned long address)
static inline bool smap_violation(int error_code, struct pt_regs *regs)
{
- if (!IS_ENABLED(CONFIG_X86_SMAP))
- return false;
-
- if (!static_cpu_has(X86_FEATURE_SMAP))
+ if (!cpu_feature_enabled(X86_FEATURE_SMAP))
return false;
if (error_code & X86_PF_USER)
|