diff options
author | Leonard Crestez <leonard.crestez@nxp.com> | 2019-08-08 19:54:08 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-10-05 12:47:55 +0200 |
commit | 70fd2442bb008b8920ff37f428bc283c8e193660 (patch) | |
tree | 826153e5ac05100851090a8b2531903f55888370 | |
parent | be1c92c485f7aedfe281432908d33b3087a4705b (diff) |
PM / devfreq: passive: Use non-devm notifiers
[ Upstream commit 0ef7c7cce43f6ecc2b96d447e69b2900a9655f7c ]
The devfreq passive governor registers and unregisters devfreq
transition notifiers on DEVFREQ_GOV_START/GOV_STOP using devm wrappers.
If devfreq itself is registered with devm then a warning is triggered on
rmmod from devm_devfreq_unregister_notifier. Call stack looks like this:
devm_devfreq_unregister_notifier+0x30/0x40
devfreq_passive_event_handler+0x4c/0x88
devfreq_remove_device.part.8+0x6c/0x9c
devm_devfreq_dev_release+0x18/0x20
release_nodes+0x1b0/0x220
devres_release_all+0x78/0x84
device_release_driver_internal+0x100/0x1c0
driver_detach+0x4c/0x90
bus_remove_driver+0x7c/0xd0
driver_unregister+0x2c/0x58
platform_driver_unregister+0x10/0x18
imx_devfreq_platdrv_exit+0x14/0xd40 [imx_devfreq]
This happens because devres_release_all will first remove all the nodes
into a separate todo list so the nested devres_release from
devm_devfreq_unregister_notifier won't find anything.
Fix the warning by calling the non-devm APIS for frequency notification.
Using devm wrappers is not actually useful for a governor anyway: it
relies on the devfreq core to correctly match the GOV_START/GOV_STOP
notifications.
Fixes: 996133119f57 ("PM / devfreq: Add new passive governor")
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
-rw-r--r-- | drivers/devfreq/governor_passive.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/devfreq/governor_passive.c b/drivers/devfreq/governor_passive.c index 673ad8cc9a1d..4222d3c1efb9 100644 --- a/drivers/devfreq/governor_passive.c +++ b/drivers/devfreq/governor_passive.c @@ -168,12 +168,12 @@ static int devfreq_passive_event_handler(struct devfreq *devfreq, p_data->this = devfreq; nb->notifier_call = devfreq_passive_notifier_call; - ret = devm_devfreq_register_notifier(dev, parent, nb, + ret = devfreq_register_notifier(parent, nb, DEVFREQ_TRANSITION_NOTIFIER); break; case DEVFREQ_GOV_STOP: - devm_devfreq_unregister_notifier(dev, parent, nb, - DEVFREQ_TRANSITION_NOTIFIER); + WARN_ON(devfreq_unregister_notifier(parent, nb, + DEVFREQ_TRANSITION_NOTIFIER)); break; default: break; |