Re: [PATCH 28/35] kasan: define KASAN_GRANULE_SIZE for HW_TAGS

From: Andrey Konovalov
Date: Thu Aug 27 2020 - 08:27:20 EST


On Thu, Aug 27, 2020 at 1:05 PM Vincenzo Frascino
<vincenzo.frascino@xxxxxxx> wrote:
>
>
>
> On 8/27/20 11:41 AM, Catalin Marinas wrote:
> > On Fri, Aug 14, 2020 at 07:27:10PM +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@xxxxxxxxxx>
> >> ---
> >> mm/kasan/kasan.h | 6 ++++++
> >> 1 file changed, 6 insertions(+)
> >>
> >> diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h
> >> index 1d3c7c6ce771..4d8e229f8e01 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.h>
> >
> > You could only include the new asm/mte-def.h file (currently mte_asm.h).
> >
>
> Agreed, we should only include asm/mte-def.h here since after the suggested
> modification will be sufficient for the purpose.

Will do in v2.

>
> >> +#define KASAN_GRANULE_SIZE (MTE_GRANULE_SIZE)
> >> +#endif
> >> +
> >> #define KASAN_GRANULE_MASK (KASAN_GRANULE_SIZE - 1)
> >>
> >> #define KASAN_TAG_KERNEL 0xFF /* native kernel pointers tag */
> >> --
> >> 2.28.0.220.ged08abb693-goog
> >>
> >
>
> --
> Regards,
> Vincenzo