From: Dave Hansen <[email protected]>

Currently, all of the checks for KAISER are compile-time checks.
We also need runtime checks if we are going to turn it on/off at
runtime.

Add a function to do that.

Signed-off-by: Dave Hansen <[email protected]>
Cc: Moritz Lipp <[email protected]>
Cc: Daniel Gruss <[email protected]>
Cc: Michael Schwarz <[email protected]>
Cc: Richard Fellner <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: [email protected]
---

 b/arch/x86/include/asm/kaiser.h |    5 +++++
 b/include/linux/kaiser.h        |    4 ++++
 2 files changed, 9 insertions(+)

diff -puN arch/x86/include/asm/kaiser.h~kaiser-dynamic-check-func 
arch/x86/include/asm/kaiser.h
--- a/arch/x86/include/asm/kaiser.h~kaiser-dynamic-check-func   2017-11-08 
10:45:40.224681368 -0800
+++ b/arch/x86/include/asm/kaiser.h     2017-11-08 10:45:40.229681368 -0800
@@ -50,6 +50,11 @@ extern void kaiser_remove_mapping(unsign
  */
 extern void kaiser_init(void);
 
+static inline bool kaiser_active(void)
+{
+       extern int kaiser_enabled;
+       return kaiser_enabled;
+}
 #endif
 
 #endif /* __ASSEMBLY__ */
diff -puN include/linux/kaiser.h~kaiser-dynamic-check-func 
include/linux/kaiser.h
--- a/include/linux/kaiser.h~kaiser-dynamic-check-func  2017-11-08 
10:45:40.225681368 -0800
+++ b/include/linux/kaiser.h    2017-11-08 10:45:40.229681368 -0800
@@ -25,5 +25,9 @@ static inline int kaiser_add_mapping(uns
        return 0;
 }
 
+static inline bool kaiser_active(void)
+{
+       return 0;
+}
 #endif /* !CONFIG_KAISER */
 #endif /* _INCLUDE_KAISER_H */
_

Reply via email to