Re: [PATCH v2 33/37] kasan, arm64: implement HW_TAGS runtime

[Marco Elver]

On Tue, Sep 15, 2020 at 11:16PM +0200, Andrey Konovalov wrote:

> diff --git a/include/linux/kasan.h b/include/linux/kasan.h
> index 875bbcedd994..613c9d38eee5 100644
> --- a/include/linux/kasan.h
> +++ b/include/linux/kasan.h
> @@ -184,7 +184,7 @@ static inline void kasan_record_aux_stack(void *ptr) {}
>  
>  #endif /* CONFIG_KASAN_GENERIC */
>  
> -#ifdef CONFIG_KASAN_SW_TAGS
> +#if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS)
>  
>  void kasan_init_tags(void);
>  
> @@ -193,7 +193,7 @@ void *kasan_reset_tag(const void *addr);
>  bool kasan_report(unsigned long addr, size_t size,
>  		bool is_write, unsigned long ip);
>  
> -#else /* CONFIG_KASAN_SW_TAGS */
> +#else /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */
>  
>  static inline void kasan_init_tags(void) { }
>  
> @@ -202,7 +202,7 @@ static inline void *kasan_reset_tag(const void *addr)
>  	return (void *)addr;
>  }
>  
> -#endif /* CONFIG_KASAN_SW_TAGS */
> +#endif /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS*/
>  
>  #ifdef CONFIG_KASAN_VMALLOC

It's not visible by looking at this diff, but there is some
#ifdef-redundancy that I do not understand where it came from.

This is what I have to fix it:

diff --git a/include/linux/kasan.h b/include/linux/kasan.h
index 613c9d38eee5..80a0e5b11f2b 100644
--- a/include/linux/kasan.h
+++ b/include/linux/kasan.h
@@ -40,6 +40,12 @@ static inline void *kasan_mem_to_shadow(const void *addr)
 int kasan_add_zero_shadow(void *start, unsigned long size);
 void kasan_remove_zero_shadow(void *start, unsigned long size);
 
+/* Enable reporting bugs after kasan_disable_current() */
+extern void kasan_enable_current(void);
+
+/* Disable reporting bugs for current task */
+extern void kasan_disable_current(void);
+
 #else /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
 
 static inline int kasan_add_zero_shadow(void *start, unsigned long size)
@@ -50,18 +56,6 @@ static inline void kasan_remove_zero_shadow(void *start,
 					unsigned long size)
 {}
 
-#endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
-
-#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
-
-/* Enable reporting bugs after kasan_disable_current() */
-extern void kasan_enable_current(void);
-
-/* Disable reporting bugs for current task */
-extern void kasan_disable_current(void);
-
-#else /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
-
 static inline void kasan_enable_current(void) {}
 static inline void kasan_disable_current(void) {}