On Tue, Jun 17, 2025 at 12:23:20PM +0800, Baolu Lu wrote:

On 6/17/25 10:25, Nicolin Chen wrote:

quoted

quoted

quoted

  struct iommufd_eventq {
  	struct iommufd_object obj;
  	struct iommufd_ctx *ictx;

diff --git a/drivers/iommu/iommufd/device.c b/drivers/iommu/iommufd/device.c
index 9293722b9cff..ad33f1e41a24 100644
--- a/drivers/iommu/iommufd/device.c
+++ b/drivers/iommu/iommufd/device.c

@@ -1084,7 +1084,39 @@ void iommufd_access_destroy_object(struct iommufd_object *obj)
  	if (access->ioas)
  		WARN_ON(iommufd_access_change_ioas(access, NULL));
  	mutex_unlock(&access->ioas_lock);
-	iommufd_ctx_put(access->ictx);
+	if (access->ops)
+		iommufd_ctx_put(access->ictx);

I was hoping we could null the ictx to signal internal? That didn't
work out?

access->ictx should be NULL for internal. It should have been:
+	if (access->ictx)
+		iommufd_ctx_put(access->ictx);

access->ictx could be treated as user ownership token. If it's NULL,
there is no user ownership, indicating it's owned by the kernel. This is
the concept here?

Yes

Jason