hisi_acc_vfio_pci: fix the queue parameter anomaly issue

When the number of QPs initialized by the device, as read via vft, is zero,
it indicates either an abnormal device configuration or an abnormal read
result.
Returning 0 directly in this case would allow the live migration operation
to complete successfully, leading to incorrect parameter configuration after
migration and preventing the service from recovering normal functionality.
Therefore, in such situations, an error should be returned to roll back the
live migration operation.

Signed-off-by: Longfang Liu <liulongfang@huawei.com>
Link: https://lore.kernel.org/r/20260122020205.2884497-5-liulongfang@huawei.com
Signed-off-by: Alex Williamson <alex@shazbot.org>

Author: Longfang Liu

drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c

@@ -426,7 +426,7 @@ static int vf_qm_check_match(struct hisi_acc_vf_core_device *hisi_acc_vdev,
 	ret = qm_get_vft(vf_qm, &vf_qm->qp_base);
 	if (ret <= 0) {
 		dev_err(dev, "failed to get vft qp nums\n");
-		return ret;
+		return ret < 0 ? ret : -EINVAL;
 	}
 
 	if (ret != vf_data->qp_num) {