From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ian Campbell <ian.campbell@citrix.com>
Subject: Re: [PATCH for-4.6] libxl: move calling
 libxl__arch_domain_construct_memmap to right place
Date: Wed, 5 Aug 2015 12:06:22 +0100
Message-ID: <1438772782.9747.59.camel@citrix.com>
References: <1438770198-5581-1-git-send-email-wei.liu2@citrix.com>
	<1438771134.9747.51.camel@citrix.com>
	<20150805104342.GH26074@zion.uk.xensource.com>
	<1438771735.9747.54.camel@citrix.com>
	<20150805105807.GI26074@zion.uk.xensource.com>
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Return-path: <xen-devel-bounces@lists.xen.org>
Received: from mail6.bemta14.messagelabs.com ([193.109.254.103])
	by lists.xen.org with esmtp (Exim 4.72)
	(envelope-from <prvs=6526c00a7=Ian.Campbell@citrix.com>)
	id 1ZMwXC-0007ka-69
	for xen-devel@lists.xenproject.org; Wed, 05 Aug 2015 11:06:58 +0000
In-Reply-To: <20150805105807.GI26074@zion.uk.xensource.com>
List-Unsubscribe: <http://lists.xen.org/cgi-bin/mailman/options/xen-devel>,
	<mailto:xen-devel-request@lists.xen.org?subject=unsubscribe>
List-Post: <mailto:xen-devel@lists.xen.org>
List-Help: <mailto:xen-devel-request@lists.xen.org?subject=help>
List-Subscribe: <http://lists.xen.org/cgi-bin/mailman/listinfo/xen-devel>,
	<mailto:xen-devel-request@lists.xen.org?subject=subscribe>
Sender: xen-devel-bounces@lists.xen.org
Errors-To: xen-devel-bounces@lists.xen.org
To: Wei Liu <wei.liu2@citrix.com>
Cc: xen-devel@lists.xenproject.org, Ian Jackson <ian.jackson@eu.citrix.com>, "Chen, Tiejun" <tiejun.chen@intel.com>
List-Id: xen-devel@lists.xenproject.org

On Wed, 2015-08-05 at 11:58 +0100, Wei Liu wrote:
> On Wed, Aug 05, 2015 at 11:48:55AM +0100, Ian Campbell wrote:
> > On Wed, 2015-08-05 at 11:43 +0100, Wei Liu wrote:
> > > On Wed, Aug 05, 2015 at 11:38:54AM +0100, Ian Campbell wrote:
> > > > On Wed, 2015-08-05 at 11:23 +0100, Wei Liu wrote:
> > > > > This function was called in the wrong place, because both
> > > > > libxl__vnuma_build_vmemrange_hvm and xc_hvm_build rely on its 
> > > > > output.
> > > > 
> > > > What is the effect of this call being in the wrong place? 
> > > > Presumably 
> > > > one or
> > > > the other of those functions reaches the wrong conclusion?
> > > 
> > > Originally, by the time that function got called, all guest pages 
> > > were
> > > already populated.  The end result is E820 map disagrees with what 
> > > vNUMA
> > > says and what address ranges memory actually resides, i.e. risk of 
> > > guest
> > > accessing region that doesn't have backing pages.
> > 
> > Ouch. This should certainly be explained in the commit message.
> > 
> > With that: Acked-by: Ian Campbell <ian.campbell@citrix.com>
> > 
> 
> I will post v2 shortly with that information in commit message.
> 
> > Although perhaps we should wait for confirmation this fix doesn't 
> > regress
> > RMRR somehow?
> > 
> 
> I doubt it will. The code as-is is already broken for RMRR. But let's
> wait till tomorrow for Tiejun to reply.
> 
> If he doesn't reply by tomorrow, I suggest we apply v2 first and
> fix up any subsequent issues later.

Agreed.