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Date: Thu, 12 Jul 2018 18:20:39 +0200
From: Oleg Nesterov <oleg@redhat.com>
Subject: Re: [PATCHv2 1/2] mm: Fix vma_is_anonymous() false-positives
Message-ID: <20180712162039.GA16175@redhat.com>
References: <20180712145626.41665-1-kirill.shutemov@linux.intel.com>
 <20180712145626.41665-2-kirill.shutemov@linux.intel.com>
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To: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>, Dmitry Vyukov <dvyukov@google.com>, Andrea Arcangeli <aarcange@redhat.com>, linux-mm@kvack.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org

Kirill, I am not trying to review this change (but it looks good to me),
just a silly question...

On 07/12, Kirill A. Shutemov wrote:
>
> This can be fixed by assigning anonymous VMAs own vm_ops and not relying
> on it being NULL.

I agree, this makes sense, but...

> If ->mmap() failed to set ->vm_ops, mmap_region() will set it to
> dummy_vm_ops.

Shouldn't this change alone fix the problem?

Oleg.