[PATCH v2 2/3] iommu/virtio: Handle iommu_device_register() failures

[Weimin Xiong]

From: Xiong Weimin <xiongweimin@xxxxxxxxxx>

From: Xiong Weimin <xiongweimin@xxxxxxxxxx>

iommu_device_register() returns an error when the IOMMU core fails to
register the hardware instance or probe the buses. viommu_probe()
currently ignores that error and continues as if the device was
registered successfully.

Propagate the failure and unwind the sysfs entry and virtqueues that
were set up earlier. Clear the driver data on the error path as well,
since it is set before registration so bus probing can find the
virtio-IOMMU instance.

Reviewed-by: Will Deacon <will@xxxxxxxxxx>
Signed-off-by: Xiong Weimin <xiongweimin@xxxxxxxxxx>
---
 drivers/iommu/virtio-iommu.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c
index 587fc1319..fb19d0bf4 100644
--- a/drivers/iommu/virtio-iommu.c
+++ b/drivers/iommu/virtio-iommu.c
@@ -1234,9 +1234,11 @@ static int viommu_probe(struct virtio_device *vdev)
 	if (ret)
 		goto err_free_vqs;
 
-	vdev->priv = viommu;
-
-	iommu_device_register(&viommu->iommu, &viommu_ops, parent_dev);
+	ret = iommu_device_register(&viommu->iommu, &viommu_ops, parent_dev);
+	if (ret)
+		goto err_free_sysfs;
 
 	dev_info(dev, "input address: %u bits\n",
 		 order_base_2(viommu->geometry.aperture_end));
@@ -1244,8 +1246,12 @@ static int viommu_probe(struct virtio_device *vdev)
 
 	return 0;
 
+err_free_sysfs:
+	iommu_device_sysfs_remove(&viommu->iommu);
 err_free_vqs:
 	vdev->config->del_vqs(vdev);
+err_clear_priv:
+	vdev->priv = NULL;
 
 	return ret;
 }
-- 
2.43.0