Hello Dave Jiang,
The patch 6e7f3ee97bbe: "dmaengine: idxd: move dsa_drv support to
compatible mode" from Jul 15, 2021, leads to the following static
checker warning:
drivers/dma/idxd/compat.c:66 bind_store()
error: uninitialized symbol 'alt_drv'.
drivers/dma/idxd/compat.c
33 static ssize_t bind_store(struct device_driver *drv, const char *buf, size_t count)
34 {
35 struct bus_type *bus = drv->bus;
36 struct device *dev;
37 struct device_driver *alt_drv;
38 int rc = -ENODEV;
39 struct idxd_dev *idxd_dev;
40
41 dev = bus_find_device_by_name(bus, NULL, buf);
42 if (!dev || dev->driver || drv != &dsa_drv.drv)
43 return -ENODEV;
44
45 idxd_dev = confdev_to_idxd_dev(dev);
46 if (is_idxd_dev(idxd_dev)) {
47 alt_drv = driver_find("idxd", bus);
48 if (!alt_drv)
49 return -ENODEV;
50 } else if (is_idxd_wq_dev(idxd_dev)) {
^^^^^^^^^^^^^^^^^^^^^^^^
Presumably this condition is always true but the static checker is not
smart enough to figure it out.
51 struct idxd_wq *wq = confdev_to_wq(dev);
52
53 if (is_idxd_wq_kernel(wq)) {
54 alt_drv = driver_find("dmaengine", bus);
55 if (!alt_drv)
56 return -ENODEV;
57 } else if (is_idxd_wq_user(wq)) {
58 alt_drv = driver_find("user", bus);
59 if (!alt_drv)
60 return -ENODEV;
61 } else {
62 return -ENODEV;
63 }
64 }
65
66 rc = device_driver_attach(alt_drv, dev);
67 if (rc < 0)
68 return rc;
69
70 return count;
71 }
regards,
dan carpenter
