Re: [PATCH v3 32/39] kasan: define KASAN_GRANULE_SIZE for HW_TAGS

elver
2020-10-01T17:58:52Z

On Fri, Sep 25, 2020 at 12:50AM +0200, Andrey Konovalov wrote:
> Hardware tag-based KASAN has granules of MTE_GRANULE_SIZE. Define
> KASAN_GRANULE_SIZE to MTE_GRANULE_SIZE for CONFIG_KASAN_HW_TAGS.
>
> Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>

Reviewed-by: Marco Elver <elver@google.com>

> ---
> Change-Id: I5d1117e6a991cbca00d2cfb4ba66e8ae2d8f513a
> ---
> mm/kasan/kasan.h | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h
> index 9c73f324e3ce..bd51ab72c002 100644
> --- a/mm/kasan/kasan.h
> +++ b/mm/kasan/kasan.h
> @@ -5,7 +5,13 @@
> #include <linux/kasan.h>
> #include <linux/stackdepot.h>
>
> +#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
> #define KASAN_GRANULE_SIZE (1UL << KASAN_SHADOW_SCALE_SHIFT)
> +#else
> +#include <asm/mte-kasan.h>
> +#define KASAN_GRANULE_SIZE (MTE_GRANULE_SIZE)

Why braces? Shouldn't MTE_GRANULE_SIZE already have braces?

> +#endif
> +
> #define KASAN_GRANULE_MASK (KASAN_GRANULE_SIZE - 1)
> #define KASAN_GRANULE_PAGE (KASAN_GRANULE_SIZE << PAGE_SHIFT)
>
> --
> 2.28.0.681.g6f77f65b4e-goog
>