On 22.01.19 13:44, Cornelia Huck wrote:
> On Tue, 22 Jan 2019 10:41:43 +0100
> David Hildenbrand <da...@redhat.com> wrote:
>
>> We decided to always create the PCI host bridge, even if 'zpci' is not
>> enabled (due to migration compatibility). This however right now allows
>> to add zPCI/PCI devices to a VM although the guest will never actually see
>> them, confusing people that are using a simple CPU model that has no
>> 'zpci' enabled - "Why isn't this working" (David Hildenbrand)
>>
>> Let's check for 'zpci' and at least print a warning that this will not
>> work as expected. We could also bail out, however that might break
>> existing QEMU commandlines.
>>
>> Signed-off-by: David Hildenbrand <da...@redhat.com>
>> ---
>> hw/s390x/s390-pci-bus.c | 5 +++++
>> 1 file changed, 5 insertions(+)
>>
>> diff --git a/hw/s390x/s390-pci-bus.c b/hw/s390x/s390-pci-bus.c
>> index b86a8bdcd4..e7d4f49611 100644
>> --- a/hw/s390x/s390-pci-bus.c
>> +++ b/hw/s390x/s390-pci-bus.c
>> @@ -863,6 +863,11 @@ static void s390_pcihost_pre_plug(HotplugHandler
>> *hotplug_dev, DeviceState *dev,
>> {
>> S390pciState *s = S390_PCI_HOST_BRIDGE(hotplug_dev);
>>
>> + if (!s390_has_feat(S390_FEAT_ZPCI)) {
>> + warn_report("Adding PCI or zPCI devices without the 'zpci' CPU
>> feature."
>> + " The guest will not be able to see/use these
>> devices.");
>> + }
>> +
>> if (object_dynamic_cast(OBJECT(dev), TYPE_PCI_DEVICE)) {
>> PCIDevice *pdev = PCI_DEVICE(dev);
>>
>
> That's hotplug only, isn't it? IIRC coldplugging already fails?
>
No, applies also to coldplugging.
--
Thanks,
David / dhildenb
