@@ -147,11 +147,10 @@ static int devfreq_passive_notifier_call(struct notifier_block *nb,
}
static int devfreq_passive_event_handler(struct devfreq *devfreq,
unsigned int event, void *data)
{
- struct device *dev = devfreq->dev.parent;
struct devfreq_passive_data *p_data
= (struct devfreq_passive_data *)devfreq->data;
struct devfreq *parent = (struct devfreq *)p_data->parent;
struct notifier_block *nb = &p_data->nb;
int ret = 0;
@@ -163,16 +162,16 @@ static int devfreq_passive_event_handler(struct devfreq *devfreq,
case DEVFREQ_GOV_START:
if (!p_data->this)
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;
}
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") Cc: stable@vger.kernel.org Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com> Acked-by: Chanwoo Choi <cw00.choi@samsung.com> --- Changes since v2: * Add fixes: tag and reorder to be similar with other patches * No code changes Link to v2: https://patchwork.kernel.org/patch/11091119/ Sorry Changes since v1: * Remove unused variable Link to v1: https://patchwork.kernel.org/patch/11084541/ drivers/devfreq/governor_passive.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-)