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From:   Souptick Joarder <jrdr.linux@gmail.com>
Date:   Sat, 11 May 2019 13:40:47 +0530
Message-ID: <CAFqt6zbxMKydJa=-TbPTWwxK-XJYyg=d-tV8AWfNSAA1Q2ugfA@mail.gmail.com>
Subject: Re: [PATCH] mm: Change count_mm_mlocked_page_nr return type
To:     Weikang shi <swkhack@gmail.com>
Cc:     Linux-MM <linux-mm@kvack.org>, linux-kernel@vger.kernel.org
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On Mon, Apr 22, 2019 at 4:08 PM Weikang shi <swkhack@gmail.com> wrote:
>
> From: swkhack <swkhack@gmail.com>
>
> In 64-bit machine,the value of "vma->vm_end - vma->vm_start"
> maybe negative in 32bit int and the "count >> PAGE_SHIFT"'s rusult

s/rusult/result.

> will be wrong.So change the local variable and return
> value to unsigned long will fix the problem.
>
> Signed-off-by: swkhack <swkhack@gmail.com>
> ---
>  mm/mlock.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/mm/mlock.c b/mm/mlock.c
> index 080f3b364..d614163f5 100644
> --- a/mm/mlock.c
> +++ b/mm/mlock.c
> @@ -636,11 +636,11 @@ static int apply_vma_lock_flags(unsigned long start, size_t len,
>   * is also counted.
>   * Return value: previously mlocked page counts
>   */
> -static int count_mm_mlocked_page_nr(struct mm_struct *mm,
> +static unsigned long count_mm_mlocked_page_nr(struct mm_struct *mm,
>                 unsigned long start, size_t len)
>  {
>         struct vm_area_struct *vma;
> -       int count = 0;
> +       unsigned long count = 0;
>
>         if (mm == NULL)
>                 mm = current->mm;
> --
> 2.17.1
>