From mboxrd@z Thu Jan  1 00:00:00 1970
From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Subject: Re: [PATCH] tools/hvmloader: Don't perform AML hotplug
 debugging in production
Date: Mon, 30 Mar 2015 11:47:47 -0400
Message-ID: <20150330154747.GF31851@l.oracle.com>
References: <1427725219-21376-1-git-send-email-andrew.cooper3@citrix.com>
	<20150330152229.GD31851@l.oracle.com> <55196BF9.2090905@citrix.com>
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Return-path: <xen-devel-bounces@lists.xen.org>
Content-Disposition: inline
In-Reply-To: <55196BF9.2090905@citrix.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: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: Keir Fraser <keir@xen.org>, Jan Beulich <JBeulich@suse.com>, Xen-devel <xen-devel@lists.xen.org>
List-Id: xen-devel@lists.xenproject.org

On Mon, Mar 30, 2015 at 04:30:01PM +0100, Andrew Cooper wrote:
> On 30/03/15 16:22, Konrad Rzeszutek Wilk wrote:
> > On Mon, Mar 30, 2015 at 03:20:19PM +0100, Andrew Cooper wrote:
> >> It is number of vmexits and a moderate quantity of qemu logging which can
> >> safely be avoided when not specifically debugging a PCI hotplug issue.
> > Could we just make qemu-X not include this data when the we
> > run in production? And in the field if this needs to be diagnosed
> > we can just pass in an extra flag to QEMU and it would do it?
> 
> What do we not include?  This is data which gets bundled into hvmloader
> itself.
> 
> A little while ago, I proposed a different solution:
> 
> http://lists.xen.org/archives/html/xen-devel/2014-01/msg01526.html

.. in which I proposed an path that you had choosen in this patch.
> 
> which allowed this to all be controlled at runtime.  The important point
> is to avoid the vmexits if not needed, rather than to simply ignore the
> debugging they are giving.

<nods>

I know I've been using this in the field (so no need to deploy a
new build) - but then eventually I had to build an custom Xen binary.

Anyhow thank you for refreshing my memory on this patchset.

and in regards to the patch:
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

> 
> ~Andrew