Re: [Qemu-devel] [PATCH v1 4/4] s390x/zpci: properly fail if the zPCI device cannot be created

[Cornelia Huck <cohuck@redhat.com>]

On Mon,  5 Nov 2018 12:03:13 +0100
David Hildenbrand <david@redhat.com> wrote:

> Right now, errors during realize()/pre_plug/plug of the zPCI device
> would result in QEMU crashing instead of failing nicely when creating
> a zPCI device for a PCI device.
> 
> Signed-off-by: David Hildenbrand <david@redhat.com>
> ---
>  hw/s390x/s390-pci-bus.c | 25 +++++++++++++++++++------
>  1 file changed, 19 insertions(+), 6 deletions(-)

Unfortunately, this patch applied as-is on top of master breaks zpci
device autogeneration:

-device zpci,target=pcidev -device virtio-net-pci,id=pcidev works

-device virtio-net-pci fails with

qemu-system-s390x: -device virtio-net-pci: zPCI device could not be created: Property '.auto_00:00.0' not found

Any idea?

[insert my usual rants about the zpci architecture here]

> 
> diff --git a/hw/s390x/s390-pci-bus.c b/hw/s390x/s390-pci-bus.c
> index 1849f9d334..4939490c7c 100644
> --- a/hw/s390x/s390-pci-bus.c
> +++ b/hw/s390x/s390-pci-bus.c
> @@ -778,17 +778,31 @@ static void s390_pci_msix_free(S390PCIBusDevice *pbdev)
>  }
>  
>  static S390PCIBusDevice *s390_pci_device_new(S390pciState *s,
> -                                             const char *target)
> +                                             const char *target, Error **errp)
>  {
> -    DeviceState *dev = NULL;
> +    Error *local_err = NULL;
> +    DeviceState *dev;
>  
>      dev = qdev_try_create(BUS(s->bus), TYPE_S390_PCI_DEVICE);
>      if (!dev) {
> +        error_setg(errp, "zPCI device could not be created");
>          return NULL;
>      }
>  
> -    qdev_prop_set_string(dev, "target", target);
> -    qdev_init_nofail(dev);
> +    object_property_set_str(OBJECT(dev), "target", target, &local_err);
> +    if (local_err) {
> +        object_unparent(OBJECT(dev));
> +        error_propagate_prepend(errp, local_err,
> +                                "zPCI device could not be created: ");
> +        return NULL;
> +    }
> +    object_property_set_bool(OBJECT(dev), true, "realized", &local_err);
> +    if (local_err) {
> +        object_unparent(OBJECT(dev));
> +        error_propagate_prepend(errp, local_err,
> +                                "zPCI device could not be created: ");
> +        return NULL;
> +    }
>  
>      return S390_PCI_DEVICE(dev);
>  }
> @@ -873,9 +887,8 @@ static void s390_pcihost_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
>  
>          pbdev = s390_pci_find_dev_by_target(s, dev->id);
>          if (!pbdev) {
> -            pbdev = s390_pci_device_new(s, dev->id);
> +            pbdev = s390_pci_device_new(s, dev->id, errp);
>              if (!pbdev) {
> -                error_setg(errp, "create zpci device failed");
>                  return;
>              }
>          }