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Date:   Mon, 8 Jun 2020 20:47:27 +0530
From:   afzal mohammed <afzal.mohd.ma@gmail.com>
To:     Arnd Bergmann <arnd@arndb.de>
Cc:     Russell King <linux@armlinux.org.uk>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: ARM: vmsplit 4g/4g
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Hi,

On Mon, Jun 08, 2020 at 04:43:57PM +0200, Arnd Bergmann wrote:

> There is another difference: get_user_pages_fast() does not return
> a  vm_area_struct pointer, which is where you would check the access
> permissions. I suppose those pointers could not be returned to callers
> that don't already hold the mmap_sem.

Ok, thanks for the details, i need to familiarize better with mm.

Regards
afzal