Re: [PATCH v3] iommu: Fix iommu selftest running test mock domain fail

[Jason Gunthorpe <jgg@ziepe.ca>]

On Wed, Sep 24, 2025 at 03:43:59PM +0800, Guixin Liu wrote:
> @@ -1077,6 +1077,7 @@ static void mock_dev_release(struct device *dev)
>  {
>  	struct mock_dev *mdev = to_mock_dev(dev);
>  
> +	iommu_mock_device_abort(&mdev->dev);
>  	ida_free(&mock_dev_ida, mdev->id);
>  	kfree(mdev);
>  }

I don't think this call is necessary? Once device_add() completes the
iommu_bus_notifier() should be active for the device.

BUS_NOTIFY_REMOVED_DEVICE triggers iommu_release_device() which does
dev_iommu_free() and frees the fwspec automatically.

The only unnatural condition is if device_add() fails then the
notifier can't run and the caller has to clean it up.

Yes?

> @@ -1126,6 +1127,10 @@ static struct mock_dev *mock_dev_create(unsigned long dev_flags)
>  		goto err_put;
>  	}
>  
> +	rc = iommu_mock_device_init(&mdev->dev, &mock_iommu.iommu_dev);
> +	if (rc)
> +		goto err_put;
> +
>  	rc = device_add(&mdev->dev);
>  	if (rc)
>  		goto err_put;

So I will suggest one further refinement to pull the device_add() into
iommu_mock_device_add() and then it can internally free the fwspec on
error and don't bother with iommu_mock_device_abort().

But other than that little note this looks fine to me.

Jason