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From:   Andrey Konovalov <andreyknvl@gmail.com>
Date:   Thu, 30 Dec 2021 20:19:01 +0100
Message-ID: <CA+fCnZd+sBzecOGBD8zR3CxXS1yjV-X3-epAb6N=ZT8rJdCU6A@mail.gmail.com>
Subject: Re: [PATCH mm v5 00/39] kasan, vmalloc, arm64: add vmalloc tagging
 support for SW/HW_TAGS
To:     Andrew Morton <akpm@linux-foundation.org>
Cc:     Marco Elver <elver@google.com>,
        Alexander Potapenko <glider@google.com>,
        Dmitry Vyukov <dvyukov@google.com>,
        Andrey Ryabinin <ryabinin.a.a@gmail.com>,
        kasan-dev <kasan-dev@googlegroups.com>,
        Linux Memory Management List <linux-mm@kvack.org>,
        Vincenzo Frascino <vincenzo.frascino@arm.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        Peter Collingbourne <pcc@google.com>,
        Evgenii Stepanov <eugenis@google.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Andrey Konovalov <andreyknvl@google.com>,
        andrey.konovalov@linux.dev
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On Thu, Dec 30, 2021 at 8:12 PM <andrey.konovalov@linux.dev> wrote:
>
> From: Andrey Konovalov <andreyknvl@google.com>
>
> Hi,
>
> This patchset adds vmalloc tagging support for SW_TAGS and HW_TAGS
> KASAN modes.
>
> The tree with patches is available here:
>
> https://github.com/xairy/linux/tree/up-kasan-vmalloc-tags-v5-akpm
>
> About half of patches are cleanups I went for along the way. None of
> them seem to be important enough to go through stable, so I decided
> not to split them out into separate patches/series.
>
> The patchset is partially based on an early version of the HW_TAGS
> patchset by Vincenzo that had vmalloc support. Thus, I added a
> Co-developed-by tag into a few patches.
>
> SW_TAGS vmalloc tagging support is straightforward. It reuses all of
> the generic KASAN machinery, but uses shadow memory to store tags
> instead of magic values. Naturally, vmalloc tagging requires adding
> a few kasan_reset_tag() annotations to the vmalloc code.
>
> HW_TAGS vmalloc tagging support stands out. HW_TAGS KASAN is based on
> Arm MTE, which can only assigns tags to physical memory. As a result,
> HW_TAGS KASAN only tags vmalloc() allocations, which are backed by
> page_alloc memory. It ignores vmap() and others.
>
> Thanks!

Hi Andrew,

Could you PTAL and consider taking this into mm?

Thanks!