Merge tag 'vfio-v5.8-rc7' of git://github.com/awilliam/linux-vfio into master

Pull VFIO fix from Alex Williamson:
 "Fix race with eventfd ctx cleared outside of mutex (Zeng Tao)"

* tag 'vfio-v5.8-rc7' of git://github.com/awilliam/linux-vfio:
  vfio/pci: fix racy on error and request eventfd ctx

Author: torvalds

drivers/vfio/pci/vfio_pci.c

@@ -521,14 +521,19 @@ static void vfio_pci_release(void *device_data)
 		vfio_pci_vf_token_user_add(vdev, -1);
 		vfio_spapr_pci_eeh_release(vdev->pdev);
 		vfio_pci_disable(vdev);
+		mutex_lock(&vdev->igate);
 		if (vdev->err_trigger) {
 			eventfd_ctx_put(vdev->err_trigger);
 			vdev->err_trigger = NULL;
 		}
+		mutex_unlock(&vdev->igate);
+
+		mutex_lock(&vdev->igate);
 		if (vdev->req_trigger) {
 			eventfd_ctx_put(vdev->req_trigger);
 			vdev->req_trigger = NULL;
 		}
+		mutex_unlock(&vdev->igate);
 	}
 
 	mutex_unlock(&vdev->reflck->lock);