[PATCH v6 07/10] s390/vfio_ccw: cancel existing workqueues

[Eric Farman]

The initialization of the io_work and crw_work workqueues begs the
question of whether they should be un-initialized. Add the corresponding
cleanup tags in _release_dev to ensure work isn't dispatched after
the private struct is free'd.

Suggested-by: Matthew Rosato <mjrosato@xxxxxxxxxxxxx>
Fixes: e5f84dbaea59 ("vfio: ccw: return I/O results asynchronously")
Fixes: 3f02cb2fd9d2 ("vfio-ccw: Wire up the CRW irq and CRW region")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Eric Farman <farman@xxxxxxxxxxxxx>
---
 drivers/s390/cio/vfio_ccw_ops.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c
index 032a1cdf4df7..bd488e40e153 100644
--- a/drivers/s390/cio/vfio_ccw_ops.c
+++ b/drivers/s390/cio/vfio_ccw_ops.c
@@ -136,6 +136,10 @@ static void vfio_ccw_mdev_release_dev(struct vfio_device *vdev)
 		kfree(crw);
 	}
 
+	/* Should be empty, but just in case */
+	cancel_work_sync(&private->io_work);
+	cancel_work_sync(&private->crw_work);
+
 	kmem_cache_free(vfio_ccw_crw_region, private->crw_region);
 	kmem_cache_free(vfio_ccw_schib_region, private->schib_region);
 	kmem_cache_free(vfio_ccw_cmd_region, private->cmd_region);
@@ -202,6 +206,10 @@ static void vfio_ccw_mdev_close_device(struct vfio_device *vdev)
 		container_of(vdev, struct vfio_ccw_private, vdev);
 
 	vfio_ccw_fsm_event(private, VFIO_CCW_EVENT_CLOSE);
+
+	cancel_work_sync(&private->io_work);
+	cancel_work_sync(&private->crw_work);
+
 	vfio_ccw_unregister_dev_regions(private);
 }
 
-- 
2.53.0