Re: [PATCH v5 3/6] kasan: Add report for async mode

[Catalin Marinas]

On Thu, Jan 21, 2021 at 04:39:40PM +0000, Vincenzo Frascino wrote:
> diff --git a/include/linux/kasan.h b/include/linux/kasan.h
> index bb862d1f0e15..b0a1d9dfa85c 100644
> --- a/include/linux/kasan.h
> +++ b/include/linux/kasan.h
> @@ -351,6 +351,8 @@ static inline void *kasan_reset_tag(const void *addr)
>  bool kasan_report(unsigned long addr, size_t size,
>  		bool is_write, unsigned long ip);
>  
> +void kasan_report_async(void);
> +
>  #else /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */
>  
>  static inline void *kasan_reset_tag(const void *addr)
> diff --git a/mm/kasan/report.c b/mm/kasan/report.c
> index 234f35a84f19..2fd6845a95e9 100644
> --- a/mm/kasan/report.c
> +++ b/mm/kasan/report.c
> @@ -358,6 +358,17 @@ void kasan_report_invalid_free(void *object, unsigned long ip)
>  	end_report(&flags);
>  }
>  
> +void kasan_report_async(void)
> +{
> +	unsigned long flags;
> +
> +	start_report(&flags);
> +	pr_err("BUG: KASAN: invalid-access\n");
> +	pr_err("Asynchronous mode enabled: no access details available\n");
> +	dump_stack();
> +	end_report(&flags);
> +}

I think the kernel test robot complains that with KASAN_SW_TAGS and
HW_TAGS disabled, the kasan_report_async() prototype is no longer
visible but you still have the non-static function definition here. So
either move kasan_report_async() out of this #ifdef or add the #ifdef
around the function definition.

It looks like the original kasan_report() prototype is declared in two
places (second one in mm/kasan/kasan.h). I'd remove the latter and try
to have a consistent approach for kasan_report() and
kasan_report_async().

-- 
Catalin