From 9f13c7165566f442484fa6c335950465ed6a2050 Mon Sep 17 00:00:00 2001 From: Cornelia Huck Date: Wed, 17 Apr 2019 13:57:38 +0100 Subject: [PATCH 21/24] s390x/pci: Warn when adding PCI devices without the 'zpci' feature RH-Author: Cornelia Huck Message-id: <20190417135741.25297-22-cohuck@redhat.com> Patchwork-id: 85803 O-Subject: [RHEL-8.1.0 qemu-kvm PATCH v2 21/24] s390x/pci: Warn when adding PCI devices without the 'zpci' feature Bugzilla: 1699070 RH-Acked-by: David Hildenbrand RH-Acked-by: Thomas Huth RH-Acked-by: Jens Freimann From: David Hildenbrand 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 (cherry picked from commit 703fef6fcf3edcbf169c90b6196fcf88f9e9765a) Signed-off-by: Cornelia Huck Signed-off-by: Danilo C. L. de Paula --- hw/s390x/s390-pci-bus.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/hw/s390x/s390-pci-bus.c b/hw/s390x/s390-pci-bus.c index a0f7245..1ba7873 100644 --- a/hw/s390x/s390-pci-bus.c +++ b/hw/s390x/s390-pci-bus.c @@ -864,6 +864,12 @@ 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); -- 1.8.3.1