1 files changed, 47 insertions, 27 deletions

diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
index f27e25112c40..8722f5effacd 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
@@ -568,23 +568,39 @@ static int vfio_fsl_mc_init_device(struct vfio_fsl_mc_device *vdev)
 		dev_err(&mc_dev->dev, "VFIO_FSL_MC: Failed to setup DPRC (%d)\n", ret);
 		goto out_nc_unreg;
 	}
+	return 0;
+
+out_nc_unreg:
+	bus_unregister_notifier(&fsl_mc_bus_type, &vdev->nb);
+	return ret;
+}
 
+static int vfio_fsl_mc_scan_container(struct fsl_mc_device *mc_dev)
+{
+	int ret;
+
+	/* non dprc devices do not scan for other devices */
+	if (!is_fsl_mc_bus_dprc(mc_dev))
+		return 0;
 	ret = dprc_scan_container(mc_dev, false);
 	if (ret) {
-		dev_err(&mc_dev->dev, "VFIO_FSL_MC: Container scanning failed (%d)\n", ret);
-		goto out_dprc_cleanup;
+		dev_err(&mc_dev->dev,
+			"VFIO_FSL_MC: Container scanning failed (%d)\n", ret);
+		dprc_remove_devices(mc_dev, NULL, 0);
+		return ret;
 	}
-
 	return 0;
+}
+
+static void vfio_fsl_uninit_device(struct vfio_fsl_mc_device *vdev)
+{
+	struct fsl_mc_device *mc_dev = vdev->mc_dev;
+
+	if (!is_fsl_mc_bus_dprc(mc_dev))
+		return;
 
-out_dprc_cleanup:
-	dprc_remove_devices(mc_dev, NULL, 0);
 	dprc_cleanup(mc_dev);
-out_nc_unreg:
 	bus_unregister_notifier(&fsl_mc_bus_type, &vdev->nb);
-	vdev->nb.notifier_call = NULL;
-
-	return ret;
 }
 
 static int vfio_fsl_mc_probe(struct fsl_mc_device *mc_dev)
@@ -607,29 +623,39 @@ static int vfio_fsl_mc_probe(struct fsl_mc_device *mc_dev)
 	}
 
 	vdev->mc_dev = mc_dev;
-
-	ret = vfio_add_group_dev(dev, &vfio_fsl_mc_ops, vdev);
-	if (ret) {
-		dev_err(dev, "VFIO_FSL_MC: Failed to add to vfio group\n");
-		goto out_group_put;
-	}
+	mutex_init(&vdev->igate);
 
 	ret = vfio_fsl_mc_reflck_attach(vdev);
 	if (ret)
-		goto out_group_dev;
+		goto out_group_put;
 
 	ret = vfio_fsl_mc_init_device(vdev);
 	if (ret)
 		goto out_reflck;
 
-	mutex_init(&vdev->igate);
+	ret = vfio_add_group_dev(dev, &vfio_fsl_mc_ops, vdev);
+	if (ret) {
+		dev_err(dev, "VFIO_FSL_MC: Failed to add to vfio group\n");
+		goto out_device;
+	}
 
+	/*
+	 * This triggers recursion into vfio_fsl_mc_probe() on another device
+	 * and the vfio_fsl_mc_reflck_attach() must succeed, which relies on the
+	 * vfio_add_group_dev() above. It has no impact on this vdev, so it is
+	 * safe to be after the vfio device is made live.
+	 */
+	ret = vfio_fsl_mc_scan_container(mc_dev);
+	if (ret)
+		goto out_group_dev;
 	return 0;
 
-out_reflck:
-	vfio_fsl_mc_reflck_put(vdev->reflck);
 out_group_dev:
 	vfio_del_group_dev(dev);
+out_device:
+	vfio_fsl_uninit_device(vdev);
+out_reflck:
+	vfio_fsl_mc_reflck_put(vdev->reflck);
 out_group_put:
 	vfio_iommu_group_put(group, dev);
 	return ret;
@@ -646,16 +672,10 @@ static int vfio_fsl_mc_remove(struct fsl_mc_device *mc_dev)
 
 	mutex_destroy(&vdev->igate);
 
+	dprc_remove_devices(mc_dev, NULL, 0);
+	vfio_fsl_uninit_device(vdev);
 	vfio_fsl_mc_reflck_put(vdev->reflck);
 
-	if (is_fsl_mc_bus_dprc(mc_dev)) {
-		dprc_remove_devices(mc_dev, NULL, 0);
-		dprc_cleanup(mc_dev);
-	}
-
-	if (vdev->nb.notifier_call)
-		bus_unregister_notifier(&fsl_mc_bus_type, &vdev->nb);
-
 	vfio_iommu_group_put(mc_dev->dev.iommu_group, dev);
 
 	return 0;