Re: [PATCH v6 07/25] iommufd/access: Add internal APIs for HW queue to use

[Baolu Lu]

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

  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?

Thanks,
baolu