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From:   Andrey Konovalov <andreyknvl@gmail.com>
Date:   Tue, 31 May 2022 21:24:57 +0200
Message-ID: <CA+fCnZdyu-iHjsciTs35bCtXuH0X-UJkfhs4P=tLq2_sHK-Rfw@mail.gmail.com>
Subject: Re: [PATCH 2/3] mm: introduce clear_highpage_tagged
To:     Andrew Morton <akpm@linux-foundation.org>
Cc:     andrey.konovalov@linux.dev, 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>,
        LKML <linux-kernel@vger.kernel.org>,
        Andrey Konovalov <andreyknvl@google.com>
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On Tue, May 31, 2022 at 7:52 PM Andrew Morton <akpm@linux-foundation.org> wrote:
>
> On Tue, 31 May 2022 17:43:49 +0200 andrey.konovalov@linux.dev wrote:
>
> > From: Andrey Konovalov <andreyknvl@google.com>
> >
> > Add a clear_highpage_tagged() helper that does clear_highpage() on a
> > page potentially tagged by KASAN.
>
> clear_highpage_kasan_tagged() would be a better name, no?

Sounds good! Will include into v2.

I also noticed there's an extra empty line at the end of the function
I need to fix.

>
> --- a/include/linux/highmem.h~mm-introduce-clear_highpage_tagged-fix
> +++ a/include/linux/highmem.h
> @@ -243,7 +243,7 @@ static inline void clear_highpage(struct
>         kunmap_local(kaddr);
>  }
>
> -static inline void clear_highpage_tagged(struct page *page)
> +static inline void clear_highpage_kasan_tagged(struct page *page)
>  {
>         u8 tag;
>
> --- a/mm/page_alloc.c~mm-introduce-clear_highpage_tagged-fix
> +++ a/mm/page_alloc.c
> @@ -1311,7 +1311,7 @@ static void kernel_init_pages(struct pag
>         /* s390's use of memset() could override KASAN redzones. */
>         kasan_disable_current();
>         for (i = 0; i < numpages; i++)
> -               clear_highpage_tagged(page + i);
> +               clear_highpage_kasan_tagged(page + i);
>         kasan_enable_current();
>  }
>
> _
>