From mboxrd@z Thu Jan  1 00:00:00 1970
From: =?UTF-8?Q?Roger_Pau_Monn=c3=a9?= <roger.pau@citrix.com>
Subject: Re: [PATCH 5/5] x86/HVM: don't setup an intercept
 handler for IO port 0xcf8 unconditionally
Date: Thu, 14 Jan 2016 09:35:19 +0100
Message-ID: <56975DC7.3070905@citrix.com>
References: <1452688338-70075-1-git-send-email-roger.pau@citrix.com>
	<1452688338-70075-6-git-send-email-roger.pau@citrix.com>
	<56968BA902000078000C66BF@prv-mh.provo.novell.com>
	<8122e183a2d14f759d983acf2777be06@AMSPEX02CL03.citrite.net>
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.bemta4.messagelabs.com ([85.158.143.247])
	by lists.xen.org with esmtp (Exim 4.72)
	(envelope-from <prvs=81484c792=roger.pau@citrix.com>)
	id 1aJdNL-0003vt-VZ
	for xen-devel@lists.xenproject.org; Thu, 14 Jan 2016 08:35:24 +0000
In-Reply-To: <8122e183a2d14f759d983acf2777be06@AMSPEX02CL03.citrite.net>
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: Paul Durrant <Paul.Durrant@citrix.com>, Jan Beulich <JBeulich@suse.com>
Cc: Andrew Cooper <Andrew.Cooper3@citrix.com>, "xen-devel@lists.xenproject.org" <xen-devel@lists.xenproject.org>
List-Id: xen-devel@lists.xenproject.org

El 13/01/16 a les 17.48, Paul Durrant ha escrit:
>> -----Original Message-----
>> From: Jan Beulich [mailto:JBeulich@suse.com]
>> Sent: 13 January 2016 16:39
>> To: Paul Durrant; Roger Pau Monne
>> Cc: Andrew Cooper; xen-devel@lists.xenproject.org
>> Subject: Re: [PATCH 5/5] x86/HVM: don't setup an intercept handler for IO
>> port 0xcf8 unconditionally
>>
>>>>> On 13.01.16 at 13:32, <roger.pau@citrix.com> wrote:
>>> Only intercept accesses to IO port 0xcf8 if there's at least one IOREQ
>>> server, otherwise it makes no sense since the only code that uses the value
>>> stored by hvm_access_cf8 is the IOREQ server.
>>
>> Afaict an ioreq server could also attach subsequently - Paul?
>>
> 
> Indeed, ioreq servers can come and go at any time.

Right, then I will have to prevent hvm_access_cf8 from being added if
the domain is the hardware domain, otherwise it overlaps with the Dom0
passthrough intercept (handle_pvh_io).

Roger.