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Subject: Re: [PATCH v8 30/43] arm64: kasan: Allow enabling in-kernel MTE
To:     Andrey Konovalov <andreyknvl@google.com>,
        Catalin Marinas <catalin.marinas@arm.com>
Cc:     Will Deacon <will.deacon@arm.com>,
        Dmitry Vyukov <dvyukov@google.com>,
        Andrey Ryabinin <aryabinin@virtuozzo.com>,
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        Marco Elver <elver@google.com>,
        Evgenii Stepanov <eugenis@google.com>,
        Branislav Rankov <Branislav.Rankov@arm.com>,
        Kevin Brodsky <kevin.brodsky@arm.com>,
        Andrew Morton <akpm@linux-foundation.org>,
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        Linux Memory Management List <linux-mm@kvack.org>,
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From:   Vincenzo Frascino <vincenzo.frascino@arm.com>
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Date:   Fri, 6 Nov 2020 11:11:21 +0000
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Hi Catalin,

On 11/5/20 6:09 PM, Andrey Konovalov wrote:
>> Ah, I got there eventually in patch 38. Too many indirections ;) (I'm
>> sure we could have trimmed them down a bit, hw_init_tags ==
>> arch_init_tags == mte_init_tags).
> The idea with these indirections was to make hw_tags.c to not directly
> call MTE stuff and abstract away the underlying memory tagging
> implementation. We won't know for sure how fitting these abstractions
> are before we add another memory tagging implementation though :)
> 

I agree with Andrey, because in future the sparc architecture might want to
support HW KASAN hence keeping a generic infrastructure adds some value.

-- 
Regards,
Vincenzo