[PATCH] device-dax: fix cdev leak

[Dan Williams]

If device_add() fails, cleanup the cdev. Otherwise, we leak a kobj_map()
with a stale device number.

Fixes: ba09c01d2fa8 ("dax: convert to the cdev api")
Cc: <stable@xxxxxxxxxxxxxxx>
Cc: Logan Gunthorpe <logang@xxxxxxxxxxxx>
Reported-by: Jason Gunthorpe <jgunthorpe@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
 drivers/dax/dax.c |    1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/dax/dax.c b/drivers/dax/dax.c
index ed758b74ddf0..0f8008dd0b0c 100644
--- a/drivers/dax/dax.c
+++ b/drivers/dax/dax.c
@@ -724,6 +724,7 @@ struct dax_dev *devm_create_dax_dev(struct dax_region *dax_region,
 	dev_set_name(dev, "dax%d.%d", dax_region->id, dax_dev->id);
 	rc = device_add(dev);
 	if (rc) {
+		cdev_del(&dax_dev->cdev);
 		put_device(dev);
 		return ERR_PTR(rc);
 	}