Re: [Qemu-devel] [PATCH 2/3] hw/virtio-net.c: set config size using host features

["Andreas Färber" <afaerber@suse.de>]

Am 07.03.2013 17:27, schrieb Christian Borntraeger:
>> It's a bug in both virtio-ccw that features=0 when get_features is
>> called.  You can also tell this with:
>>
>> [10:02 AM] anthony@titi:~/git/qemu/hw/s390x$ grep DEFINE_VIRTIO_NET_FEATURES *
>> virtio-ccw.c:    DEFINE_VIRTIO_NET_FEATURES(VirtioCcwDevice, host_features[0]),
>>
>> So virtio-s390 is doing it wrong, but virtio-ccw looks like its doing it
>> right.
> 
> At least, this patch seems to work. (That also implies, that a transport
> must not hide virtio feature bits).

To me it indicates that the use of the old qdev property setters is
hiding errors resulting from trying to set not-existing properties.
If we would set the properties in a way that gets us an Error* on
failure like the object_property_set_*() do, we would notice on machine
creation (or device_add).

Andreas

> 
> 
> From: Christian Borntraeger <borntraeger@de.ibm.com>
> Date: Thu, 7 Mar 2013 17:21:41 +0100
> Subject: [PATCH] Allow virtio-net features for legacy s390 virtio bus
> 
> Enable all virtio-net features for the legacy s390 virtio bus.
> This also fixes
> kernel BUG at /usr/src/packages/BUILD/kernel-default-3.0.58/linux-3.0/drivers/s390/kvm/kvm_virtio.c:121!
> 
> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
> ---
>  hw/s390x/s390-virtio-bus.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/hw/s390x/s390-virtio-bus.c b/hw/s390x/s390-virtio-bus.c
> index 1200691..a8a8e19 100644
> --- a/hw/s390x/s390-virtio-bus.c
> +++ b/hw/s390x/s390-virtio-bus.c
> @@ -399,6 +399,7 @@ static const VirtIOBindings virtio_s390_bindings = {
>  
>  static Property s390_virtio_net_properties[] = {
>      DEFINE_NIC_PROPERTIES(VirtIOS390Device, nic),
> +    DEFINE_VIRTIO_NET_FEATURES(VirtIOS390Device, host_features),
>      DEFINE_PROP_UINT32("x-txtimer", VirtIOS390Device,
>                         net.txtimer, TX_TIMER_INTERVAL),
>      DEFINE_PROP_INT32("x-txburst", VirtIOS390Device,
> 


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