Re: [Qemu-devel] [PATCH 3/3] s390-virtio-bus: sync config only when config_len is not zero

[Alexander Graf]

On 26.04.2013, at 10:34, Jason Wang wrote:

> virtio-rng-s390 has zero config length, so no need to sync its config 
> otherwise
> qemu will crash since vdev->config is NULL.

Why is it NULL?


Alex

> 
> Cc: Alexander Graf <address@hidden>
> Cc: Richard Henderson <address@hidden>
> Signed-off-by: Jason Wang <address@hidden>
> ---
> hw/s390x/s390-virtio-bus.c |    4 ++++
> 1 files changed, 4 insertions(+), 0 deletions(-)
> 
> diff --git a/hw/s390x/s390-virtio-bus.c b/hw/s390x/s390-virtio-bus.c
> index dabbc2e..0f83516 100644
> --- a/hw/s390x/s390-virtio-bus.c
> +++ b/hw/s390x/s390-virtio-bus.c
> @@ -350,6 +350,10 @@ void s390_virtio_device_sync(VirtIOS390Device *dev)
>     dev->feat_offs = cur_offs + dev->feat_len;
>     cur_offs += dev->feat_len * 2;
> 
> +    if (!dev->vdev->config_len) {
> +        return;
> +    }
> +
>     /* Sync config space */
>     if (dev->vdev->get_config) {
>         dev->vdev->get_config(dev->vdev, dev->vdev->config);
> -- 
> 1.7.1
> 
>