[PATCH 2/2] compiler: check for __SANITIZE_ADDRESS__ instead of CONFIG_KASAN

[Ahmad Fatoum]

The current Linux definition for __no_kasan_or_inline adds a notrace
attribute and checks __SANITIZE_ADDRESS__ instead of CONFIG_KASAN.

Checking __SANITIZE_ADDRESS__ is better because it also applies to
CONFIG_ASAN, so import the Linux version into <linux/compiler_types.h>,
which is the same location it's defined at in Linux.

Signed-off-by: Ahmad Fatoum <a.fatoum at barebox.org>
---
 include/linux/compiler.h       | 12 ------------
 include/linux/compiler_types.h | 20 ++++++++++++++++++++
 2 files changed, 20 insertions(+), 12 deletions(-)

diff --git a/include/linux/compiler.h b/include/linux/compiler.h
index e7dc9ba0a590..4953121711ba 100644
--- a/include/linux/compiler.h
+++ b/include/linux/compiler.h
@@ -168,18 +168,6 @@ void ftrace_likely_update(struct ftrace_likely_data *f, int val,
 
 #include <linux/types.h>
 
-#ifdef CONFIG_KASAN
-/*
- * We can't declare function 'inline' because __no_sanitize_address confilcts
- * with inlining. Attempt to inline it may cause a build failure.
- * 	https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67368
- * '__maybe_unused' allows us to avoid defined-but-not-used warnings.
- */
-# define __no_kasan_or_inline __no_sanitize_address __maybe_unused
-#else
-# define __no_kasan_or_inline __always_inline
-#endif
-
 #endif /* __KERNEL__ */
 
 /**
diff --git a/include/linux/compiler_types.h b/include/linux/compiler_types.h
index cd618e7dece1..87ab117aca13 100644
--- a/include/linux/compiler_types.h
+++ b/include/linux/compiler_types.h
@@ -378,6 +378,26 @@ struct ftrace_likely_data {
  */
 #define noinline_for_stack noinline
 
+/*
+ * Sanitizer helper attributes: Because using __always_inline and
+ * __no_sanitize_* conflict, provide helper attributes that will either expand
+ * to __no_sanitize_* in compilation units where instrumentation is enabled
+ * (__SANITIZE_*__), or __always_inline in compilation units without
+ * instrumentation (__SANITIZE_*__ undefined).
+ */
+#ifdef __SANITIZE_ADDRESS__
+/*
+ * We can't declare function 'inline' because __no_sanitize_address conflicts
+ * with inlining. Attempt to inline it may cause a build failure.
+ *     https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67368
+ * '__maybe_unused' allows us to avoid defined-but-not-used warnings.
+ */
+# define __no_kasan_or_inline __no_sanitize_address notrace __maybe_unused
+# define __no_sanitize_or_inline __no_kasan_or_inline
+#else
+# define __no_kasan_or_inline __always_inline
+#endif
+
 #ifndef __no_sanitize_or_inline
 #define __no_sanitize_or_inline __always_inline
 #endif
-- 
2.39.5