Re: [Qemu-devel] [PATCH] hw/arm/virt: Allow zero address for PCI IO space

[Laurent Vivier <lvivier@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
>