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Date:   Fri, 28 Feb 2020 16:45:44 +0100
From:   Claudio Imbrenda <imbrenda@linux.ibm.com>
To:     linux-next@vger.kernel.org, akpm@linux-foundation.org
Cc:     borntraeger@de.ibm.com, david@redhat.com, aarcange@redhat.com,
        linux-mm@kvack.org, frankja@linux.ibm.com, sfr@canb.auug.org.au,
        jhubbard@nvidia.com, linux-kernel@vger.kernel.org,
        linux-s390@vger.kernel.org
Subject: Re: [RFC v1 1/2] fixup for 9947ea2c1e608e32669d5caeb67b3e3fba3309e8
 "mm/gup: track FOLL_PIN pages"
In-Reply-To: <20200228154322.329228-2-imbrenda@linux.ibm.com>
References: <20200228154322.329228-1-imbrenda@linux.ibm.com>
        <20200228154322.329228-2-imbrenda@linux.ibm.com>
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sorry, this one was a mistake, please ignore


On Fri, 28 Feb 2020 16:43:20 +0100
Claudio Imbrenda <imbrenda@linux.ibm.com> wrote:

> in case pin fails, we need to unpin, just a put_page will not be
> enough
> 
> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
> ---
>  mm/gup.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/mm/gup.c b/mm/gup.c
> index f589299b0d4a..0b9a806898f3 100644
> --- a/mm/gup.c
> +++ b/mm/gup.c
> @@ -2134,7 +2134,10 @@ static int gup_pte_range(pmd_t pmd, unsigned
> long addr, unsigned long end, goto pte_unmap;
>  
>  		if (unlikely(pte_val(pte) != pte_val(*ptep))) {
> -			put_page(head);
> +			if (flags & FOLL_GET)
> +				put_page(head);
> +			else if (flags & FOLL_PIN)
> +				unpin_user_page(head);
>  			goto pte_unmap;
>  		}
>