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Date: Thu, 31 May 2018 16:37:10 -0700 (PDT)
From: Hugh Dickins <hughd@google.com>
Subject: Re: [PATCH] mm/shmem: Zero out unused vma fields in
 shmem_pseudo_vma_init()
In-Reply-To: <20180531155256.a5f557c9e620a6d7e85e4ca1@linux-foundation.org>
Message-ID: <alpine.LSU.2.11.1805311635410.13735@eggly.anvils>
References: <20180531135602.20321-1-kirill.shutemov@linux.intel.com> <20180531155256.a5f557c9e620a6d7e85e4ca1@linux-foundation.org>
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To: Andrew Morton <akpm@linux-foundation.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>, Hugh Dickins <hughd@google.com>, linux-mm@kvack.org, linux-kernel@vger.kernel.org

On Thu, 31 May 2018, Andrew Morton wrote:
> On Thu, 31 May 2018 16:56:02 +0300 "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> wrote:
> 
> > shmem/tmpfs uses pseudo vma to allocate page with correct NUMA policy.
> > 
> > The pseudo vma doesn't have vm_page_prot set. We are going to encode
> > encryption KeyID in vm_page_prot. Having garbage there causes problems.
> > 
> > Zero out all unused fields in the pseudo vma.
> > 
> 
> So there are no known problems in the current mainline kernel?

Correct - if we limit ourselves to the area of the shmem pseudo-vma :)

Hugh