This is a note to let you know that I've just added the patch titled PM / devfreq: Don't fail devfreq_dev_release if not in list to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: pm-devfreq-don-t-fail-devfreq_dev_release-if-not-in-.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 30741c54f1d9eff90c8146cfa43e11237d4846b1 Author: Leonard Crestez <leonard.crestez@xxxxxxx> Date: Thu Nov 14 01:21:31 2019 +0200 PM / devfreq: Don't fail devfreq_dev_release if not in list [ Upstream commit 42a6b25e67df6ee6675e8d1eaf18065bd73328ba ] Right now devfreq_dev_release will print a warning and abort the rest of the cleanup if the devfreq instance is not part of the global devfreq_list. But this is a valid scenario, for example it can happen if the governor can't be found or on any other init error that happens after device_register. Initialize devfreq->node to an empty list head in devfreq_add_device so that list_del becomes a safe noop inside devfreq_dev_release and we can continue the rest of the cleanup. Signed-off-by: Leonard Crestez <leonard.crestez@xxxxxxx> Reviewed-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx> Reviewed-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx> Signed-off-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c index df62e38de5f5..fb696957eb21 100644 --- a/drivers/devfreq/devfreq.c +++ b/drivers/devfreq/devfreq.c @@ -482,11 +482,6 @@ static int devfreq_notifier_call(struct notifier_block *nb, unsigned long type, static void _remove_devfreq(struct devfreq *devfreq) { mutex_lock(&devfreq_list_lock); - if (IS_ERR(find_device_devfreq(devfreq->dev.parent))) { - mutex_unlock(&devfreq_list_lock); - dev_warn(&devfreq->dev, "releasing devfreq which doesn't exist\n"); - return; - } list_del(&devfreq->node); mutex_unlock(&devfreq_list_lock); @@ -558,6 +553,7 @@ struct devfreq *devfreq_add_device(struct device *dev, devfreq->dev.parent = dev; devfreq->dev.class = devfreq_class; devfreq->dev.release = devfreq_dev_release; + INIT_LIST_HEAD(&devfreq->node); devfreq->profile = profile; strncpy(devfreq->governor_name, governor_name, DEVFREQ_NAME_LEN); devfreq->previous_freq = profile->initial_freq;