diff options
| author | David Gow <davidgow@google.com> | 2023-07-20 14:45:09 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-08-12 13:06:16 +0200 |
| commit | 699fb50d99039a50e7494de644f96c889279aca3 (patch) | |
| tree | 1e9d5ada2fc2bcbab3e672655054a0ab223c4626 /drivers/base/core.c | |
| parent | b4cc44301b9d35e9420cebecc31fb3964e53499a (diff) | |
drivers: base: Free devm resources when unregistering a device
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@google.com>
Signed-off-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20230720-kunit-devm-inconsistencies-test-v3-3-6aa7e074f373@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/base/core.c')
| -rw-r--r-- | drivers/base/core.c | 11 |
1 files changed, 11 insertions, 0 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); |