[PATCH] dmaengine: idxd: fix runaway module ref count on device driver bind

[Dave Jiang <dave.jiang@xxxxxxxxx>]

idxd_config_bus_probe() calls try_module_get() but never calls module_put()
when it fails. Thus with every failed attempt, the ref count goes up. Add
module_put() in failure paths.

Fixes: c52ca478233c ("dmaengine: idxd: add configuration component of driver")

Reported-by: Jerry Chen <jerry.t.chen@xxxxxxxxx>
Signed-off-by: Dave Jiang <dave.jiang@xxxxxxxxx>
---
 drivers/dma/idxd/sysfs.c |    3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/dma/idxd/sysfs.c b/drivers/dma/idxd/sysfs.c
index 6d907fe150aa..298855ca934f 100644
--- a/drivers/dma/idxd/sysfs.c
+++ b/drivers/dma/idxd/sysfs.c
@@ -124,6 +124,7 @@ static int idxd_config_bus_probe(struct device *dev)
 		rc = idxd_device_config(idxd);
 		if (rc < 0) {
 			spin_unlock_irqrestore(&idxd->dev_lock, flags);
+			module_put(THIS_MODULE);
 			dev_warn(dev, "Device config failed: %d\n", rc);
 			return rc;
 		}
@@ -132,6 +133,7 @@ static int idxd_config_bus_probe(struct device *dev)
 		rc = idxd_device_enable(idxd);
 		if (rc < 0) {
 			spin_unlock_irqrestore(&idxd->dev_lock, flags);
+			module_put(THIS_MODULE);
 			dev_warn(dev, "Device enable failed: %d\n", rc);
 			return rc;
 		}
@@ -142,6 +144,7 @@ static int idxd_config_bus_probe(struct device *dev)
 		rc = idxd_register_dma_device(idxd);
 		if (rc < 0) {
 			spin_unlock_irqrestore(&idxd->dev_lock, flags);
+			module_put(THIS_MODULE);
 			dev_dbg(dev, "Failed to register dmaengine device\n");
 			return rc;
 		}