From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S1756094AbcIFUSA (ORCPT <rfc822;w@1wt.eu>);
        Tue, 6 Sep 2016 16:18:00 -0400
Received: from mail.linuxfoundation.org ([140.211.169.12]:59153 "EHLO
        mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S1755563AbcIFUR6 (ORCPT
        <rfc822;linux-kernel@vger.kernel.org>);
        Tue, 6 Sep 2016 16:17:58 -0400
Date: Tue, 6 Sep 2016 13:17:56 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Dan Williams <dan.j.williams@intel.com>
Cc: linux-nvdimm@ml01.01.org, Toshi Kani <toshi.kani@hpe.com>,
        Matthew Wilcox <mawilcox@microsoft.com>,
        Nilesh Choudhury <nilesh.choudhury@oracle.com>,
        linux-kernel@vger.kernel.org, stable@vger.kernel.org,
        linux-mm@kvack.org, Ross Zwisler <ross.zwisler@linux.intel.com>,
        "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        Kai Zhang <kai.ka.zhang@oracle.com>
Subject: Re: [PATCH 4/5] mm: fix cache mode of dax pmd mappings
Message-Id: <20160906131756.6b6c6315b7dfba3a9d5f233a@linux-foundation.org>
In-Reply-To: <147318058165.30325.16762406881120129093.stgit@dwillia2-desk3.amr.corp.intel.com>
References: <147318056046.30325.5100892122988191500.stgit@dwillia2-desk3.amr.corp.intel.com>
        <147318058165.30325.16762406881120129093.stgit@dwillia2-desk3.amr.corp.intel.com>
X-Mailer: Sylpheed 3.4.1 (GTK+ 2.24.23; x86_64-pc-linux-gnu)
Mime-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Tue, 06 Sep 2016 09:49:41 -0700 Dan Williams <dan.j.williams@intel.com> wrote:

> track_pfn_insert() is marking dax mappings as uncacheable.
> 
> It is used to keep mappings attributes consistent across a remapped range.
> However, since dax regions are never registered via track_pfn_remap(), the
> caching mode lookup for dax pfns always returns _PAGE_CACHE_MODE_UC.  We do not
> use track_pfn_insert() in the dax-pte path, and we always want to use the
> pgprot of the vma itself, so drop this call.
> 
> Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
> Cc: Matthew Wilcox <mawilcox@microsoft.com>
> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: Nilesh Choudhury <nilesh.choudhury@oracle.com>
> Reported-by: Kai Zhang <kai.ka.zhang@oracle.com>
> Reported-by: Toshi Kani <toshi.kani@hpe.com>
> Cc: <stable@vger.kernel.org>
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>

Changelog fails to explain the user-visible effects of the patch.  The
stable maintainer(s) will look at this and wonder "ytf was I sent
this".

After fixing that, 

Acked-by: Andrew Morton <akpm@linux-foundation.org>