From dfd402a4c4baae42398ce9180ff424d589b8bffc Mon Sep 17 00:00:00 2001 From: Marco Elver Date: Thu, 14 Nov 2019 19:02:54 +0100 Subject: kcsan: Add Kernel Concurrency Sanitizer infrastructure Kernel Concurrency Sanitizer (KCSAN) is a dynamic data-race detector for kernel space. KCSAN is a sampling watchpoint-based data-race detector. See the included Documentation/dev-tools/kcsan.rst for more details. This patch adds basic infrastructure, but does not yet enable KCSAN for any architecture. Signed-off-by: Marco Elver Acked-by: Paul E. McKenney Signed-off-by: Paul E. McKenney --- include/linux/compiler.h | 37 +++++++++++++++++++++++++++++-------- 1 file changed, 29 insertions(+), 8 deletions(-) (limited to 'include/linux/compiler.h') diff --git a/include/linux/compiler.h b/include/linux/compiler.h index 5e88e7e33abe..c42fa83f23fb 100644 --- a/include/linux/compiler.h +++ b/include/linux/compiler.h @@ -178,6 +178,7 @@ void ftrace_likely_update(struct ftrace_likely_data *f, int val, #endif #include +#include #define __READ_ONCE_SIZE \ ({ \ @@ -193,12 +194,6 @@ void ftrace_likely_update(struct ftrace_likely_data *f, int val, } \ }) -static __always_inline -void __read_once_size(const volatile void *p, void *res, int size) -{ - __READ_ONCE_SIZE; -} - #ifdef CONFIG_KASAN /* * We can't declare function 'inline' because __no_sanitize_address confilcts @@ -207,18 +202,44 @@ void __read_once_size(const volatile void *p, void *res, int size) * '__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 -static __no_kasan_or_inline +#ifdef __SANITIZE_THREAD__ +/* + * Rely on __SANITIZE_THREAD__ instead of CONFIG_KCSAN, to avoid not inlining in + * compilation units where instrumentation is disabled. + */ +# define __no_kcsan_or_inline __no_sanitize_thread notrace __maybe_unused +# define __no_sanitize_or_inline __no_kcsan_or_inline +#else +# define __no_kcsan_or_inline __always_inline +#endif + +#ifndef __no_sanitize_or_inline +#define __no_sanitize_or_inline __always_inline +#endif + +static __no_kcsan_or_inline +void __read_once_size(const volatile void *p, void *res, int size) +{ + kcsan_check_atomic_read(p, size); + __READ_ONCE_SIZE; +} + +static __no_sanitize_or_inline void __read_once_size_nocheck(const volatile void *p, void *res, int size) { __READ_ONCE_SIZE; } -static __always_inline void __write_once_size(volatile void *p, void *res, int size) +static __no_kcsan_or_inline +void __write_once_size(volatile void *p, void *res, int size) { + kcsan_check_atomic_write(p, size); + switch (size) { case 1: *(volatile __u8 *)p = *(__u8 *)res; break; case 2: *(volatile __u16 *)p = *(__u16 *)res; break; -- cgit v1.2.3-59-g8ed1b