Re: [PATCH v2 23/37] arm64: kasan: Add arch layer for memory tagging helpers

From: Andrey Konovalov
Date: Fri Sep 18 2020 - 10:56:27 EST


On Fri, Sep 18, 2020 at 3:00 PM Marco Elver <elver@xxxxxxxxxx> wrote:
>
> On Tue, Sep 15, 2020 at 11:16PM +0200, 'Andrey Konovalov' via kasan-dev wrote:
> > This patch add a set of arch_*() memory tagging helpers currently only
> > defined for arm64 when hardware tag-based KASAN is enabled. These helpers
> > will be used by KASAN runtime to implement the hardware tag-based mode.
> >
> > The arch-level indirection level is introduced to simplify adding hardware
> > tag-based KASAN support for other architectures in the future by defining
> > the appropriate arch_*() macros.
> >
> > Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
> > Co-developed-by: Vincenzo Frascino <vincenzo.frascino@xxxxxxx>
> > Signed-off-by: Vincenzo Frascino <vincenzo.frascino@xxxxxxx>
> > ---
> > Change-Id: I42b0795a28067872f8308e00c6f0195bca435c2a
> > ---
> > arch/arm64/include/asm/memory.h | 8 ++++++++
> > mm/kasan/kasan.h | 19 +++++++++++++++++++
> > 2 files changed, 27 insertions(+)
> >
> > diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h
> > index e424fc3a68cb..268a3b6cebd2 100644
> > --- a/arch/arm64/include/asm/memory.h
> > +++ b/arch/arm64/include/asm/memory.h
> > @@ -231,6 +231,14 @@ static inline const void *__tag_set(const void *addr, u8 tag)
> > return (const void *)(__addr | __tag_shifted(tag));
> > }
> >
> > +#ifdef CONFIG_KASAN_HW_TAGS
> > +#define arch_init_tags(max_tag) mte_init_tags(max_tag)
> > +#define arch_get_random_tag() mte_get_random_tag()
> > +#define arch_get_mem_tag(addr) mte_get_mem_tag(addr)
> > +#define arch_set_mem_tag_range(addr, size, tag) \
> > + mte_set_mem_tag_range((addr), (size), (tag))
>
> Suggested edit below, assuming you're fine with checkpatch.pl's new
> 100col limit:
>
> -#define set_mem_tag_range(addr, size, tag) \
> - arch_set_mem_tag_range((addr), (size), (tag))
> +#define set_mem_tag_range(addr, size, tag) arch_set_mem_tag_range((addr), (size), (tag))

Will do in v3, thanks!