device_del() destroys the vfio-dev/vfioX under the sysfs for vfio_device. There is no reason to keep it while the device is going to be unregistered. This movement is also a preparation for adding vfio_device cdev. Kernel should remove the cdev node of the vfio_device to avoid new registration refcount increment while the device is going to be unregistered. Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx> Tested-by: Zhenzhong Duan <zhenzhong.duan@xxxxxxxxx> Signed-off-by: Yi Liu <yi.l.liu@xxxxxxxxx> --- drivers/vfio/vfio_main.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c index 6d45caa1f9a0..294bb5ecfc1c 100644 --- a/drivers/vfio/vfio_main.c +++ b/drivers/vfio/vfio_main.c @@ -338,6 +338,9 @@ void vfio_unregister_group_dev(struct vfio_device *device) */ vfio_device_group_unregister(device); + /* Balances device_add in register path */ + device_del(&device->device); + vfio_device_put_registration(device); rc = try_wait_for_completion(&device->comp); while (rc <= 0) { @@ -361,9 +364,6 @@ void vfio_unregister_group_dev(struct vfio_device *device) } } - /* Balances device_add in register path */ - device_del(&device->device); - /* Balances vfio_device_set_group in register path */ vfio_device_remove_group(device); } -- 2.34.1