diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index a8130a4..a5ee213 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -358,10 +358,19 @@ static ssize_t class_pktcdvd_store_add(struct class *c, const char *buf,
 					size_t count)
 {
 	unsigned int major, minor;
+
 	if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
+		/* pkt_setup_dev() expects caller to hold reference to self */
+		if (!try_module_get(THIS_MODULE))
+			return -ENODEV;
+
 		pkt_setup_dev(MKDEV(major, minor), NULL);
+
+		module_put(THIS_MODULE);
+
 		return count;
 	}
+
 	return -EINVAL;
 }