diff --git a/arch/x86/include/asm/string_64.h b/arch/x86/include/asm/string_64.h
index 888731ccf1f6..c1e14cee0722 100644
--- a/arch/x86/include/asm/string_64.h
+++ b/arch/x86/include/asm/string_64.h
@@ -85,25 +85,6 @@ char *strcpy(char *dest, const char *src);
 char *strcat(char *dest, const char *src);
 int strcmp(const char *cs, const char *ct);
 
-#if (defined(CONFIG_KASAN) && !defined(__SANITIZE_ADDRESS__))
-/*
- * For files that not instrumented (e.g. mm/slub.c) we
- * should use not instrumented version of mem* functions.
- */
-
-#undef memcpy
-#define memcpy(dst, src, len) __memcpy(dst, src, len)
-#undef memmove
-#define memmove(dst, src, len) __memmove(dst, src, len)
-#undef memset
-#define memset(s, c, n) __memset(s, c, n)
-
-#ifndef __NO_FORTIFY
-#define __NO_FORTIFY /* FORTIFY_SOURCE uses __builtin_memcpy, etc. */
-#endif
-
-#endif
-
 #ifdef CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE
 #define __HAVE_ARCH_MEMCPY_FLUSHCACHE 1
 void __memcpy_flushcache(void *dst, const void *src, size_t cnt);