On Thu, Aug 27, 2020 at 1:31 PM Vincenzo Frascino <vincenzo.frascino@xxxxxxx> wrote: > > 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? I think we can reword the help text to say that it enables tag-based KASAN mode that is backed by the hardware in general, and mention that this is currently only implemented for arm64 through MTE. I don't think it makes sense to provide a common arch interface at this point to keep the code simpler. We can do that when (and if) another hardware backend is added.
