From: David Gow <davidgow@xxxxxxxxxx>
In the current code, devres_release_all() only gets called if the device
has a bus and has been probed.
This leads to issues when using bus-less or driver-less devices where
the device might never get freed if a managed resource holds a reference
to the device. This is happening in the DRM framework for example.
We should thus call devres_release_all() in the device_del() function to
make sure that the device-managed actions are properly executed when the
device is unregistered, even if it has neither a bus nor a driver.
This is effectively the same change than commit 2f8d16a996da ("devres:
release resources on device_del()") that got reverted by commit
a525a3ddeaca ("driver core: free devres in device_release") over
memory leaks concerns.
This patch effectively combines the two commits mentioned above to
release the resources both on device_del() and device_release() and get
the best of both worlds.
Fixes: a525a3ddeaca ("driver core: free devres in device_release")
Signed-off-by: David Gow <davidgow@xxxxxxxxxx>
Signed-off-by: Maxime Ripard <mripard@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230720-kunit-devm-inconsistencies-test-v3-3-6aa7e074f373@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/base/core.c | 11 +++++++++++
drivers/base/test/platform-device-test.c | 2 --
drivers/base/test/root-device-test.c | 2 --
3 files changed, 11 insertions(+), 4 deletions(-)
diff --git a/drivers/base/core.c b/drivers/base/core.c
index 3dff5037943e..6ceaf50f5a67 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -3817,6 +3817,17 @@ void device_del(struct device *dev)
device_platform_notify_remove(dev);
device_links_purge(dev);
+ /*
+ * If a device does not have a driver attached, we need to clean
+ * up any managed resources. We do this in device_release(), but
+ * it's never called (and we leak the device) if a managed
+ * resource holds a reference to the device. So release all
+ * managed resources here, like we do in driver_detach(). We
+ * still need to do so again in device_release() in case someone
+ * adds a new resource after this point, though.
+ */
+ devres_release_all(dev);
+
bus_notify(dev, BUS_NOTIFY_REMOVED_DEVICE);
kobject_uevent(&dev->kobj, KOBJ_REMOVE);
glue_dir = get_glue_dir(dev);
diff --git a/drivers/base/test/platform-device-test.c b/drivers/base/test/platform-device-test.c
index b6ebf1dcdffb..1ae5ce8bd366 100644
--- a/drivers/base/test/platform-device-test.c
+++ b/drivers/base/test/platform-device-test.c
@@ -87,8 +87,6 @@ static void platform_device_devm_register_get_unregister_with_devm_test(struct k
struct test_priv *priv = test->priv;
int ret;
- kunit_skip(test, "This needs to be fixed in the core.");
-
pdev = platform_device_alloc(DEVICE_NAME, PLATFORM_DEVID_NONE);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, pdev);
diff --git a/drivers/base/test/root-device-test.c b/drivers/base/test/root-device-test.c
index 9a3e6cccae13..780d07455f57 100644
--- a/drivers/base/test/root-device-test.c
+++ b/drivers/base/test/root-device-test.c
@@ -78,8 +78,6 @@ static void root_device_devm_register_get_unregister_with_devm_test(struct kunit
struct test_priv *priv = test->priv;
int ret;
- kunit_skip(test, "This needs to be fixed in the core.");
-
priv->dev = root_device_register(DEVICE_NAME);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, priv->dev);
--
2.34.1
