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From:   Andrey Konovalov <andreyknvl@google.com>
Date:   Thu, 27 Aug 2020 14:37:57 +0200
Message-ID: <CAAeHK+zY_MaquqrpYFVcH5XtsWT6WtREqUa897V-UpBpqoiGCQ@mail.gmail.com>
Subject: Re: [PATCH 31/35] kasan, arm64: implement HW_TAGS runtime
To:     Catalin Marinas <catalin.marinas@arm.com>
Cc:     Dmitry Vyukov <dvyukov@google.com>,
        Vincenzo Frascino <vincenzo.frascino@arm.com>,
        kasan-dev <kasan-dev@googlegroups.com>,
        Andrey Ryabinin <aryabinin@virtuozzo.com>,
        Alexander Potapenko <glider@google.com>,
        Marco Elver <elver@google.com>,
        Evgenii Stepanov <eugenis@google.com>,
        Elena Petrova <lenaptr@google.com>,
        Branislav Rankov <Branislav.Rankov@arm.com>,
        Kevin Brodsky <kevin.brodsky@arm.com>,
        Will Deacon <will.deacon@arm.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        Linux Memory Management List <linux-mm@kvack.org>,
        LKML <linux-kernel@vger.kernel.org>
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On Thu, Aug 27, 2020 at 12:45 PM Catalin Marinas
<catalin.marinas@arm.com> wrote:
>
> On Fri, Aug 14, 2020 at 07:27:13PM +0200, Andrey Konovalov wrote:
> > diff --git a/mm/kasan/mte.c b/mm/kasan/mte.c
> > new file mode 100644
> > index 000000000000..43b7d74161e5
> > --- /dev/null
> > +++ b/mm/kasan/mte.c
>
> Since this is an arm64-specific kasan backend, I wonder whether it makes
> more sense to keep it under arch/arm64 (mte-kasan.c).

I'm not sure if we do. I'd rather keep everything together, spreading
the implementation around the kernel is inconvenient. We already have
software tag-based KASAN implementation (which is also arm64-specific)
in the common code. We could, perhaps, rename mte.c into something
more generic, with other potential future hardware modes in mind.

> > diff --git a/mm/kasan/report_mte.c b/mm/kasan/report_mte.c
> > new file mode 100644
> > index 000000000000..dbbf3aaa8798
> > --- /dev/null
> > +++ b/mm/kasan/report_mte.c
>
> Same for this one.