From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Jan Beulich" <JBeulich@suse.com>
Subject: Re: [PATCH v6 1/2] xen/pvh: use a custom IO bitmap for
 PVH hardware domains
Date: Fri, 15 May 2015 08:42:12 +0100
Message-ID: <5555BF74020000780007A697@mail.emea.novell.com>
References: <1431356258-31269-1-git-send-email-roger.pau@citrix.com>
	<1431356258-31269-2-git-send-email-roger.pau@citrix.com>
	<55533B220200007800079F0A@mail.emea.novell.com>
	<5554BEFA.1020500@citrix.com>
	<5555AFFD020000780007A5E1@mail.emea.novell.com>
	<5555A168.9050108@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>
Received: from mail6.bemta3.messagelabs.com ([195.245.230.39])
	by lists.xen.org with esmtp (Exim 4.72)
	(envelope-from <JBeulich@suse.com>) id 1YtAG5-0002TD-G0
	for xen-devel@lists.xenproject.org; Fri, 15 May 2015 07:42:13 +0000
In-Reply-To: <5555A168.9050108@citrix.com>
Content-Disposition: inline
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: =?UTF-8?Q?Roger=20Pau=20Monn=C3=A9?= <roger.pau@citrix.com>
Cc: Kevin Tian <kevin.tian@intel.com>, SuraveeSuthikulpanit <suravee.suthikulpanit@amd.com>, Andrew Cooper <andrew.cooper3@citrix.com>, Eddie Dong <eddie.dong@intel.com>, Aravind Gopalakrishnan <Aravind.Gopalakrishnan@amd.com>, Jun Nakajima <jun.nakajima@intel.com>, xen-devel@lists.xenproject.org, Boris Ostrovsky <boris.ostrovsky@oracle.com>, dgdegra@tycho.nsa.gov
List-Id: xen-devel@lists.xenproject.org

>>> On 15.05.15 at 09:34, <roger.pau@citrix.com> wrote:
> El 15/05/15 a les 8.36, Jan Beulich ha escrit:
>>>>> On 14.05.15 at 17:27, <roger.pau@citrix.com> wrote:
>>> El 13/05/15 a les 11.53, Jan Beulich ha escrit:
>>>>>>> On 11.05.15 at 16:57, <roger.pau@citrix.com> wrote:
>>>>> --- a/xen/common/domain.c
>>>>> +++ b/xen/common/domain.c
>>>>> @@ -42,6 +42,7 @@
>>>>>  #include <xsm/xsm.h>
>>>>>  #include <xen/trace.h>
>>>>>  #include <xen/tmem.h>
>>>>> +#include <asm/setup.h>
>>>>>  
>>>>>  /* Linux config option: propageted to domain0 */
>>>>>  /* xen_processor_pmbits: xen control Cx, Px, ... */
>>>>> @@ -219,6 +220,7 @@ static int late_hwdom_init(struct domain *d)
>>>>>      rangeset_swap(d->iomem_caps, dom0->iomem_caps);
>>>>>  #ifdef CONFIG_X86
>>>>>      rangeset_swap(d->arch.ioport_caps, dom0->arch.ioport_caps);
>>>>> +    setup_io_bitmap(d);
>>>>>  #endif
>>>>
>>>> Considering that rangesets are getting swapped rather than
>>>> copied, I think you also need to reset Dom0's I/O bitmap here
>>>> to the ordinary, non-hardware domain one.
>>>
>>> Yes. Would it be fine to memset it and just call setup_io_bitmap on it
>>> again, or would you prefer to exchange it with the static one and free it?
>> 
>> Following how the rangesets are being treated, simply swapping
>> the two I/O bitmaps would seem to be the right approach here.
> 
> AFAICT this requires adding a new hook in hvm_function_table in order to
> implement setting the io bitmap for SVM and VMX. I don't have a problem
> with that, but it's going to need a separate patch.

Right - if there is nothing like that currently, it'll need to be added.
Of course you may want to get Daniel de Graaf's (who originally
added this non-Dom0 hardware domain code, now Cc-ed) input on
the above outline approach before going that route...

Jan