Re: [PATCH] iommu/virtio: Detach domain on endpoint release

[Jean-Philippe Brucker <jean-philippe@linaro.org>]

Hi Joerg,

On Fri, Apr 14, 2023 at 04:07:45PM +0100, Jean-Philippe Brucker wrote:
> When an endpoint is released, for example a PCIe VF is disabled or a
> function hot-unplugged, it should be detached from its domain. Send a
> DETACH request.
> 
> Fixes: edcd69ab9a32 ("iommu: Add virtio-iommu driver")
> Reported-by: Akihiko Odaki <akihiko.odaki@daynix.com>
> Link: https://lore.kernel.org/all/15bf1b00-3aa0-973a-3a86-3fa5c4d41d2c@daynix.com/
> Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>

This patch fixes device unregistration in the virtio-iommu driver, could
you please pick it up for the next batch of fixes?  It applies cleanly on
v6.4-rc1

Thanks,
Jean

> ---
>  drivers/iommu/virtio-iommu.c | 23 +++++++++++++++++++++++
>  1 file changed, 23 insertions(+)
> 
> diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c
> index 5b8fe9bfa9a5..3d3d4462359e 100644
> --- a/drivers/iommu/virtio-iommu.c
> +++ b/drivers/iommu/virtio-iommu.c
> @@ -788,6 +788,28 @@ static int viommu_attach_dev(struct iommu_domain *domain, struct device *dev)
>  	return 0;
>  }
>  
> +static void viommu_detach_dev(struct viommu_endpoint *vdev)
> +{
> +	int i;
> +	struct virtio_iommu_req_detach req;
> +	struct viommu_domain *vdomain = vdev->vdomain;
> +	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(vdev->dev);
> +
> +	if (!vdomain)
> +		return;
> +
> +	req = (struct virtio_iommu_req_detach) {
> +		.head.type	= VIRTIO_IOMMU_T_DETACH,
> +		.domain		= cpu_to_le32(vdomain->id),
> +	};
> +
> +	for (i = 0; i < fwspec->num_ids; i++) {
> +		req.endpoint = cpu_to_le32(fwspec->ids[i]);
> +		WARN_ON(viommu_send_req_sync(vdev->viommu, &req, sizeof(req)));
> +	}
> +	vdev->vdomain = NULL;
> +}
> +
>  static int viommu_map_pages(struct iommu_domain *domain, unsigned long iova,
>  			    phys_addr_t paddr, size_t pgsize, size_t pgcount,
>  			    int prot, gfp_t gfp, size_t *mapped)
> @@ -990,6 +1012,7 @@ static void viommu_release_device(struct device *dev)
>  {
>  	struct viommu_endpoint *vdev = dev_iommu_priv_get(dev);
>  
> +	viommu_detach_dev(vdev);
>  	iommu_put_resv_regions(dev, &vdev->resv_regions);
>  	kfree(vdev);
>  }
> -- 
> 2.40.0
>