diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c
index 949f4231d08a..fe71ed7890e1 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim.c
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c

@@ -62,6 +62,7 @@ struct vdpasim_virtqueue {
  
  struct vdpasim_dev_attr {
  	u64 supported_features;
+	size_t config_size;
  	int nvqs;
  	u32 id;
  

@@ -76,7 +77,8 @@ struct vdpasim {
  	struct vdpasim_dev_attr dev_attr;
  	/* spinlock to synchronize virtqueue state */
  	spinlock_t lock;
-	struct virtio_net_config config;
+	/* virtio config according to device type */
+	void *config;
  	struct vhost_iotlb *iommu;
  	void *buffer;
  	u32 status;

@@ -376,6 +378,10 @@ static struct vdpasim *vdpasim_create(struct vdpasim_dev_attr *dev_attr)
  		goto err_iommu;
  	set_dma_ops(dev, &vdpasim_dma_ops);
  
+	vdpasim->config = kzalloc(dev_attr->config_size, GFP_KERNEL);
+	if (!vdpasim->config)
+		goto err_iommu;
+
  	vdpasim->vqs = kcalloc(dev_attr->nvqs, sizeof(struct vdpasim_virtqueue),
  			       GFP_KERNEL);
  	if (!vdpasim->vqs)

@@ -516,7 +522,8 @@ static u64 vdpasim_get_features(struct vdpa_device *vdpa)
  static int vdpasim_set_features(struct vdpa_device *vdpa, u64 features)
  {
  	struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
-	struct virtio_net_config *config = &vdpasim->config;
+	struct virtio_net_config *config =
+		(struct virtio_net_config *)vdpasim->config;
  
  	/* DMA mapping must be done by driver */
  	if (!(features & (1ULL << VIRTIO_F_ACCESS_PLATFORM)))

@@ -588,8 +595,8 @@ static void vdpasim_get_config(struct vdpa_device *vdpa, unsigned int offset,
  {
  	struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
  
-	if (offset + len < sizeof(struct virtio_net_config))
-		memcpy(buf, (u8 *)&vdpasim->config + offset, len);
+	if (offset + len < vdpasim->dev_attr.config_size)
+		memcpy(buf, vdpasim->config + offset, len);
  }
  
  static void vdpasim_set_config(struct vdpa_device *vdpa, unsigned int offset,

@@ -676,6 +683,7 @@ static void vdpasim_free(struct vdpa_device *vdpa)
  	if (vdpasim->iommu)
  		vhost_iotlb_free(vdpasim->iommu);
  	kfree(vdpasim->vqs);
+	kfree(vdpasim->config);
  }
  
  static const struct vdpa_config_ops vdpasim_config_ops = {

@@ -738,6 +746,7 @@ static int __init vdpasim_dev_init(void)
  	dev_attr.id = VIRTIO_ID_NET;
  	dev_attr.supported_features = VDPASIM_NET_FEATURES;
  	dev_attr.nvqs = VDPASIM_VQ_NUM;
+	dev_attr.config_size = sizeof(struct virtio_net_config);
  	dev_attr.work_fn = vdpasim_net_work;
  
  	vdpasim_dev = vdpasim_create(&dev_attr);