Re: [PATCH 25/35] kasan: introduce CONFIG_KASAN_HW_TAGS

From: Vincenzo Frascino
Date: Thu Aug 27 2020 - 07:42:30 EST


Hi Andrey,

On 8/14/20 6:27 PM, Andrey Konovalov wrote:
> +config·KASAN_HW_TAGS
> +» bool·"Hardware·tag-based·mode"
> +» depends·on·HAVE_ARCH_KASAN_HW_TAGS
> +» depends·on·SLUB
> +» help
> +» ··Enables·hardware·tag-based·KASAN·mode.
> +
> +» ··This·mode·requires·both·Memory·Tagging·Extension·and·Top·Byte·Ignore
> +» ··support·by·the·CPU·and·therefore·is·only·supported·for·modern·arm64
> +» ··CPUs·(MTE·added·in·ARMv8.5·ISA).
> +

I do not thing we should make KASAN_HW_TAGS MTE specific especially because it
is in the common code (e.g. SPARC ADI might want to implement it in future).

Probably would be better to provide some indirection in the generic code an
implement the MTE backend entirely in arch code.

Thoughts?

--
Regards,
Vincenzo