Patch "iommu/virtio: Detach domain on endpoint release" has been added to the 6.4-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    iommu/virtio: Detach domain on endpoint release

to the 6.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     iommu-virtio-detach-domain-on-endpoint-release.patch
and it can be found in the queue-6.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit ed0cc99a82518444e4579c309fb7d1e887d66c1d
Author: Jean-Philippe Brucker <jean-philippe@xxxxxxxxxx>
Date:   Mon May 15 12:39:48 2023 +0100

    iommu/virtio: Detach domain on endpoint release
    
    [ Upstream commit 809d0810e3520da669d231303608cdf5fe5c1a70 ]
    
    When an endpoint is released, for example a PCIe VF being destroyed 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@xxxxxxxxxx>
    Link: https://lore.kernel.org/all/15bf1b00-3aa0-973a-3a86-3fa5c4d41d2c@xxxxxxxxxx/
    Signed-off-by: Jean-Philippe Brucker <jean-philippe@xxxxxxxxxx>
    Tested-by: Akihiko Odaki <akihiko.odaki@xxxxxxxxxx>
    Link: https://lore.kernel.org/r/20230515113946.1017624-2-jean-philippe@xxxxxxxxxx
    Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c
index 5b8fe9bfa9a5b..fd316a37d7562 100644
--- a/drivers/iommu/virtio-iommu.c
+++ b/drivers/iommu/virtio-iommu.c
@@ -788,6 +788,29 @@ 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)));
+	}
+	vdomain->nr_endpoints--;
+	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 +1013,7 @@ 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);
 }