Commit e33f9a16 authored by Marco Elver's avatar Marco Elver Committed by Paul E. McKenney
Browse files

kcsan: Add __no_kcsan function attribute 



Since the use of -fsanitize=thread is an implementation detail of KCSAN,
the name __no_sanitize_thread could be misleading if used widely.
Instead, we introduce the __no_kcsan attribute which is shorter and more
accurate in the context of KCSAN.

This matches the attribute name __no_kcsan_or_inline. The use of
__kcsan_or_inline itself is still required for __always_inline functions
to retain compatibility with older compilers.

Signed-off-by: default avatarMarco Elver <elver@google.com>
Signed-off-by: default avatarPaul E. McKenney <paulmck@kernel.org>
parent 71611774

include/linux/compiler-gcc.h

+1 −2
Original line number Diff line number Diff line
@@ -146,8 +146,7 @@ 
#endif



#if defined(__SANITIZE_THREAD__) && __has_attribute(__no_sanitize_thread__)

#define __no_sanitize_thread                                                   \

	__attribute__((__noinline__)) __attribute__((no_sanitize_thread))

#define __no_sanitize_thread __attribute__((no_sanitize_thread))

#else

#define __no_sanitize_thread

#endif

include/linux/compiler.h

+5 −2
Original line number Diff line number Diff line
@@ -207,12 +207,15 @@ void ftrace_likely_update(struct ftrace_likely_data *f, int val, 
# define __no_kasan_or_inline __always_inline

#endif



#define __no_kcsan __no_sanitize_thread

#ifdef __SANITIZE_THREAD__

/*

 * Rely on __SANITIZE_THREAD__ instead of CONFIG_KCSAN, to avoid not inlining in

 * compilation units where instrumentation is disabled.

 * compilation units where instrumentation is disabled. The attribute 'noinline'

 * is required for older compilers, where implicit inlining of very small

 * functions renders __no_sanitize_thread ineffective.

 */

# define __no_kcsan_or_inline __no_sanitize_thread notrace __maybe_unused

# define __no_kcsan_or_inline __no_kcsan noinline notrace __maybe_unused

# define __no_sanitize_or_inline __no_kcsan_or_inline

#else

# define __no_kcsan_or_inline __always_inline