vdpa: min vq num of vdpa device cannot be greater than max vq num

Just failed to probe the vdpa device if the min virtqueue num returned
by get_vq_num_min is greater than the max virtqueue num returned by
get_vq_num_max.

Signed-off-by: Wu Zongyong <wuzongyong@linux.alibaba.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/21199b62cc10b2a9f2cf90eeb63ad080645d881f.1635493219.git.wuzongyong@linux.alibaba.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c
index 1dc121a..d783a94 100644 (file)
--- a/drivers/vdpa/vdpa.c
+++ b/drivers/vdpa/vdpa.c
@@ -26,8 +26,16 @@ static int vdpa_dev_probe(struct device *d)
 {
        struct vdpa_device *vdev = dev_to_vdpa(d);
        struct vdpa_driver *drv = drv_to_vdpa(vdev->dev.driver);
+       const struct vdpa_config_ops *ops = vdev->config;
+       u32 max_num, min_num = 1;
        int ret = 0;
 
+       max_num = ops->get_vq_num_max(vdev);
+       if (ops->get_vq_num_min)
+               min_num = ops->get_vq_num_min(vdev);
+       if (max_num < min_num)
+               return -EINVAL;
+
        if (drv && drv->probe)
                ret = drv->probe(vdev);