From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([2001:4830:134:3::10]:42649)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <lvivier@redhat.com>) id 1Zlyzn-0000ye-2b
	for qemu-devel@nongnu.org; Tue, 13 Oct 2015 08:48:03 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <lvivier@redhat.com>) id 1ZlyzR-00007f-2m
	for qemu-devel@nongnu.org; Tue, 13 Oct 2015 08:47:58 -0400
Received: from mx1.redhat.com ([209.132.183.28]:38291)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <lvivier@redhat.com>) id 1ZlyzQ-00006r-Us
	for qemu-devel@nongnu.org; Tue, 13 Oct 2015 08:47:37 -0400
References: <1444683308-30543-1-git-send-email-agordeev@redhat.com>
	<CAFEAcA-EvesCxofDnSGGzwDxi2+5wJ+kXE4xGjrh45tVue+6dA@mail.gmail.com>
	<20151013063057.GA32581@agordeev.usersys.redhat.com>
	<CAFEAcA8RsfP2W61P8m8Vkd6ji3yvzBU8VY8zDO5RUtDNezFidA@mail.gmail.com>
	<20151013124837.GA27387@agordeev.usersys.redhat.com>
	<CAFEAcA_qW8DjJiYzuYy1_cuuOw9rWiscBmb4gyK55pUXsmFPJA@mail.gmail.com>
From: Laurent Vivier <lvivier@redhat.com>
Message-ID: <561CFD65.40407@redhat.com>
Date: Tue, 13 Oct 2015 14:47:33 +0200
MIME-Version: 1.0
In-Reply-To: <CAFEAcA_qW8DjJiYzuYy1_cuuOw9rWiscBmb4gyK55pUXsmFPJA@mail.gmail.com>
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit
Subject: Re: [Qemu-devel] [PATCH] hw/arm/virt: Allow zero address for PCI IO
	space
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Peter Maydell <peter.maydell@linaro.org>, Alexander Gordeev <agordeev@redhat.com>
Cc: Andrew Jones <drjones@redhat.com>, QEMU Developers <qemu-devel@nongnu.org>, "Michael S. Tsirkin" <mst@redhat.com>



On 13/10/2015 14:33, Peter Maydell wrote:
> On 13 October 2015 at 13:48, Alexander Gordeev <agordeev@redhat.com> wrote:
>> On Tue, Oct 13, 2015 at 09:16:34AM +0100, Peter Maydell wrote:
>>> In any case, setting pci_allow_0_address is the right thing,
>>> so we can just change the commit message in this patch.
>>
>> I will post v2 with an updated changelog then.
>>
>>> Incidentally, why is this a property on the machine
>>> and not on the PCI controller device?
>>
>> I am CC-ing Laurent Vivier who introduced the flag.
>>
>> But IMO it *is* a machine property, not PCI controller's
>> one, unless I am missing something.
> 
> I think "does this PCI controller handle BARs with
> zero addresses, or does it treat them as if the BAR
> was unmapped" is definitely a controller property...
> you might have in theory a machine with two PCI
> controllers, one of which could deal with zero-addresses
> and one of which could not.

MST asked for a global flag:

https://lists.gnu.org/archive/html/qemu-ppc/2015-07/msg00364.html

But perhaps the machine is not the good place for this global flag ?

CC: Michael for that.

> thanks
> -- PMM
>