Re: [PATCH v2 2/4] hw/virtio: gracefully handle unset vhost_dev vdev

["Michael S. Tsirkin" <mst@redhat.com>]

On Thu, Jul 28, 2022 at 02:55:01PM +0100, Alex Bennée wrote:
> I've noticed asserts firing because we query the status of vdev after
> a vhost connection is closed down. Rather than faulting on the NULL
> indirect just quietly reply false.
> 
> Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
> Message-Id: <20220726192150.2435175-8-alex.bennee@linaro.org>

Please do not include this header when you post.


> ---
>  hw/virtio/vhost.c | 10 +++++++---
>  1 file changed, 7 insertions(+), 3 deletions(-)
> 
> diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
> index 0827d631c0..f758f177bb 100644
> --- a/hw/virtio/vhost.c
> +++ b/hw/virtio/vhost.c
> @@ -306,7 +306,7 @@ static inline void vhost_dev_log_resize(struct vhost_dev *dev, uint64_t size)
>      dev->log_size = size;
>  }
>  
> -static int vhost_dev_has_iommu(struct vhost_dev *dev)
> +static bool vhost_dev_has_iommu(struct vhost_dev *dev)
>  {
>      VirtIODevice *vdev = dev->vdev;
>  
> @@ -316,8 +316,12 @@ static int vhost_dev_has_iommu(struct vhost_dev *dev)
>       * does not have IOMMU, there's no need to enable this feature
>       * which may cause unnecessary IOTLB miss/update transactions.
>       */
> -    return virtio_bus_device_iommu_enabled(vdev) &&
> -           virtio_host_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM);
> +    if (vdev) {
> +        return virtio_bus_device_iommu_enabled(vdev) &&
> +            virtio_host_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM);
> +    } else {
> +        return false;
> +    }
>  }
>  
>  static void *vhost_memory_map(struct vhost_dev *dev, hwaddr addr,
> -- 
> 2.30.2