Re: [Qemu-devel] [PATCH V2 1/5] virtio: get_features() can fail

[Jason Wang <jasowang@redhat.com>]

On 07/15/2015 05:01 PM, Cornelia Huck wrote:
> On Wed, 15 Jul 2015 13:29:57 +0800
> Jason Wang <jasowang@redhat.com> wrote:
>
>> Signed-off-by: Jason Wang <jasowang@redhat.com>
>> ---
>>  hw/9pfs/virtio-9p-device.c  | 3 ++-
>>  hw/block/virtio-blk.c       | 3 ++-
>>  hw/char/virtio-serial-bus.c | 3 ++-
>>  hw/display/virtio-gpu.c     | 3 ++-
>>  hw/input/virtio-input.c     | 3 ++-
>>  hw/net/virtio-net.c         | 3 ++-
>>  hw/scsi/vhost-scsi.c        | 3 ++-
>>  hw/scsi/virtio-scsi.c       | 3 ++-
>>  hw/virtio/virtio-balloon.c  | 3 ++-
>>  hw/virtio/virtio-bus.c      | 3 ++-
>>  hw/virtio/virtio-rng.c      | 2 +-
>>  include/hw/virtio/virtio.h  | 4 +++-
>>  12 files changed, 24 insertions(+), 12 deletions(-)
>> diff --git a/hw/virtio/virtio-bus.c b/hw/virtio/virtio-bus.c
>> index 3926f7e..febda76 100644
>> --- a/hw/virtio/virtio-bus.c
>> +++ b/hw/virtio/virtio-bus.c
>> @@ -54,7 +54,8 @@ void virtio_bus_device_plugged(VirtIODevice *vdev, Error **errp)
>>
>>      /* Get the features of the plugged device. */
>>      assert(vdc->get_features != NULL);
>> -    vdev->host_features = vdc->get_features(vdev, vdev->host_features);
>> +    vdev->host_features = vdc->get_features(vdev, vdev->host_features,
>> +                                            errp);
>>  }
>>
>>  /* Reset the virtio_bus */
> Don't you need to propagate the error instead of passing it through? Or
> am I just confused by error handling? :)
>

If I understand the code correctly. The caller (virtio_device_realize())
will propagate the error.