virtio-vdpa: Fix unchecked call to NULL set_vq_affinity

The referenced patch calls set_vq_affinity without checking if the op is
valid. This patch adds the check.

Fixes: 3dad56823b53 ("virtio-vdpa: Support interrupt affinity spreading mechanism")
Reviewed-by: Gal Pressman <gal@nvidia.com>
Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Message-Id: <20230504135053.2283816-1-dtatulea@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Feng Liu <feliu@nvidia.com>

diff --git a/drivers/virtio/virtio_vdpa.c b/drivers/virtio/virtio_vdpa.c
index eb6aee8..989e2d7 100644 (file)
--- a/drivers/virtio/virtio_vdpa.c
+++ b/drivers/virtio/virtio_vdpa.c
@@ -385,7 +385,9 @@ static int virtio_vdpa_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
                        err = PTR_ERR(vqs[i]);
                        goto err_setup_vq;
                }
-               ops->set_vq_affinity(vdpa, i, &masks[i]);
+
+               if (ops->set_vq_affinity)
+                       ops->set_vq_affinity(vdpa, i, &masks[i]);
        }
 
        cb.callback = virtio_vdpa_config_cb;