diff --git a/drivers/staging/comedi/comedi_fops.c b/drivers/staging/comedi/comedi_fops.c
index d77219a..d231193 100644
--- a/drivers/staging/comedi/comedi_fops.c
+++ b/drivers/staging/comedi/comedi_fops.c
@@ -427,6 +427,9 @@ static long comedi_unlocked_ioctl(struct file *file, unsigned int cmd,
 	if (cmd == COMEDI_DEVCONFIG) {
 		rc = do_devconfig_ioctl(dev,
 					(struct comedi_devconfig __user *)arg);
+		if (rc == 0)
+			/* Evade comedi_auto_unconfig(). */
+			dev_file_info->hardware_device = NULL;
 		goto done;
 	}