From: David Hildenbrand Date: Wed, 30 Jan 2019 15:57:30 +0000 (+0100) Subject: s390x/pci: Warn when adding PCI devices without the 'zpci' feature X-Git-Tag: v4.0.0-rc0~116^2~1 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=703fef6fcf3edcbf169c90b6196fcf88f9e9765a;p=thirdparty%2Fqemu.git s390x/pci: Warn when adding PCI devices without the 'zpci' feature 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. Reviewed-by: Thomas Huth Signed-off-by: David Hildenbrand Message-Id: <20190130155733.32742-4-david@redhat.com> Reviewed-by: Collin Walling Signed-off-by: Cornelia Huck --- diff --git a/hw/s390x/s390-pci-bus.c b/hw/s390x/s390-pci-bus.c index d85bc346172..3816fb1f11b 100644 --- a/hw/s390x/s390-pci-bus.c +++ b/hw/s390x/s390-pci-bus.c @@ -860,6 +860,12 @@ 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("Plugging a PCI/zPCI device without the 'zpci' CPU " + "feature enabled; the guest will not be able to see/use " + "this device"); + } + if (object_dynamic_cast(OBJECT(dev), TYPE_PCI_DEVICE)) { PCIDevice *pdev = PCI_DEVICE(dev);