Re: [PATCH] lib/test_hmm: Remove set but unused page variable

[Souptick Joarder <jrdr.linux@gmail.com>]

On Tue, Jul 6, 2021 at 8:26 AM Alistair Popple <apopple@nvidia.com> wrote:
>
> The HMM selftests use atomic_check_access() to check atomic access to a
> page has been revoked. It doesn't matter if the page mapping has been
> removed from the mirrored page tables as that also implies atomic access
> has been revoked. Therefore remove the unused page variable to fix this
> compiler warning:
>
>   lib/test_hmm.c:631:16: warning: variable ‘page’ set but not used [-Wunused-but-set-variable]
>
> Fixes: b659baea7546 ("mm: selftests for exclusive device memory")
> Reported-by: Hulk Robot <hulkci@huawei.com>
> Reported-by: kernel test robot <oliver.sang@intel.com>
> Reported-by: Yang Yingliang <yangyingliang@huawei.com>
> Signed-off-by: Alistair Popple <apopple@nvidia.com>

Acked-by: Souptick Joarder <jrdr.linux@gmail.com>

> ---
>  lib/test_hmm.c | 2 --
>  1 file changed, 2 deletions(-)
>
> diff --git a/lib/test_hmm.c b/lib/test_hmm.c
> index 8c55c4723692..c259842f6d44 100644
> --- a/lib/test_hmm.c
> +++ b/lib/test_hmm.c
> @@ -628,10 +628,8 @@ static int dmirror_check_atomic(struct dmirror *dmirror, unsigned long start,
>
>         for (pfn = start >> PAGE_SHIFT; pfn < (end >> PAGE_SHIFT); pfn++) {
>                 void *entry;
> -               struct page *page;
>
>                 entry = xa_load(&dmirror->pt, pfn);
> -               page = xa_untag_pointer(entry);
>                 if (xa_pointer_tag(entry) == DPT_XA_TAG_ATOMIC)
>                         return -EPERM;
>         }
> --
> 2.20.1
>
>