driver core: introduce device_set_driver() helper

commit 04d3e5461c1f5cf8eec964ab64948ebed826e95e upstream.

In preparation to closing a race when reading driver pointer in
dev_uevent() code, instead of setting device->driver pointer directly
introduce device_set_driver() helper.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/20250311052417.1846985-2-dmitry.torokhov@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/base/base.h b/drivers/base/base.h
index a8e3d8165232fde4d38ae07c9d8e5eb5918f378d..7ac16589af3cb92039f38374e4e26d7831979fb0 100644 (file)
--- a/drivers/base/base.h
+++ b/drivers/base/base.h
@@ -179,6 +179,12 @@ int driver_add_groups(struct device_driver *drv, const struct attribute_group **
 void driver_remove_groups(struct device_driver *drv, const struct attribute_group **groups);
 void device_driver_detach(struct device *dev);
 
+static inline void device_set_driver(struct device *dev, const struct device_driver *drv)
+{
+       // FIXME - this cast should not be needed "soon"
+       dev->driver = (struct device_driver *)drv;
+}
+
 int devres_release_all(struct device *dev);
 void device_block_probing(void);
 void device_unblock_probing(void);

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 197af212ef7ecb89ce3a503713c78ae224bd4866..a5b2db9720a4d5feff58913e97287a924ebe1b2d 100644 (file)
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -3688,7 +3688,7 @@ done:
        device_pm_remove(dev);
        dpm_sysfs_remove(dev);
  DPMError:
-       dev->driver = NULL;
+       device_set_driver(dev, NULL);
        bus_remove_device(dev);
  BusError:
        device_remove_attrs(dev);

diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index 0c3725c3eefa46d80140f5278f65405262731745..7e2fb159bb895b6ecc3d44848c95cc3872fe76be 100644 (file)
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -550,7 +550,7 @@ static void device_unbind_cleanup(struct device *dev)
        arch_teardown_dma_ops(dev);
        kfree(dev->dma_range_map);
        dev->dma_range_map = NULL;
-       dev->driver = NULL;
+       device_set_driver(dev, NULL);
        dev_set_drvdata(dev, NULL);
        if (dev->pm_domain && dev->pm_domain->dismiss)
                dev->pm_domain->dismiss(dev);
@@ -629,7 +629,7 @@ static int really_probe(struct device *dev, struct device_driver *drv)
        }
 
 re_probe:
-       dev->driver = drv;
+       device_set_driver(dev, drv);
 
        /* If using pinctrl, bind pins now before probing */
        ret = pinctrl_bind_pins(dev);
@@ -1014,7 +1014,7 @@ static int __device_attach(struct device *dev, bool allow_async)
                if (ret == 0)
                        ret = 1;
                else {
-                       dev->driver = NULL;
+                       device_set_driver(dev, NULL);
                        ret = 0;
                }
        } else {