[PATCH] dmaengine: idxd: fix uninit var for alt_drv

[Dave Jiang <dave.jiang@xxxxxxxxx>]

0-day detected uninitialized alt_drv variable in the bind_store() function.
The branch can be taken when device is not idxd device or wq 'struct
device'. Init alt_drv to NULL.

Fixes: 6e7f3ee97bbe ("dmaengine: idxd: move dsa_drv support to compatible mode")
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Signed-off-by: Dave Jiang <dave.jiang@xxxxxxxxx>
---
 drivers/dma/idxd/compat.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/dma/idxd/compat.c b/drivers/dma/idxd/compat.c
index d67746ee0c1a..d7616c240dcd 100644
--- a/drivers/dma/idxd/compat.c
+++ b/drivers/dma/idxd/compat.c
@@ -34,7 +34,7 @@ static ssize_t bind_store(struct device_driver *drv, const char *buf, size_t cou
 {
 	struct bus_type *bus = drv->bus;
 	struct device *dev;
-	struct device_driver *alt_drv;
+	struct device_driver *alt_drv = NULL;
 	int rc = -ENODEV;
 	struct idxd_dev *idxd_dev;