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charset=utf-8 Content-Disposition: inline In-Reply-To: <0ad496507cd7e6731e46249b1499dfdebe205c16.1569252537.git.leonard.crestez@nxp.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org On Mon, Sep 23, 2019 at 06:51:05PM +0300, Leonard Crestez wrote: > In general it is a better to initialize an object before making it > accessible externally (through device_register). > > This makes it possible to avoid relying on locking a partially > initialized object. > > Signed-off-by: Leonard Crestez > --- > drivers/devfreq/devfreq.c | 43 +++++++++++++++++++++++---------------- > 1 file changed, 25 insertions(+), 18 deletions(-) > > diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c > index 323d43315d1e..b4d2bfebb140 100644 > --- a/drivers/devfreq/devfreq.c > +++ b/drivers/devfreq/devfreq.c > @@ -587,10 +587,12 @@ static void devfreq_dev_release(struct device *dev) > mutex_unlock(&devfreq_list_lock); > > if (devfreq->profile->exit) > devfreq->profile->exit(devfreq->dev.parent); > > + kfree(devfreq->time_in_state); > + kfree(devfreq->trans_table); > mutex_destroy(&devfreq->lock); > kfree(devfreq); > } > > /** > @@ -670,44 +672,43 @@ struct devfreq *devfreq_add_device(struct device *dev, > devfreq->max_freq = devfreq->scaling_max_freq; > > devfreq->suspend_freq = dev_pm_opp_get_suspend_opp_freq(dev); > atomic_set(&devfreq->suspend_count, 0); > > - dev_set_name(&devfreq->dev, "devfreq%d", > - atomic_inc_return(&devfreq_no)); > - err = device_register(&devfreq->dev); > - if (err) { > - mutex_unlock(&devfreq->lock); > - put_device(&devfreq->dev); > - goto err_out; > - } > - > - devfreq->trans_table = devm_kzalloc(&devfreq->dev, > + devfreq->trans_table = kzalloc( > array3_size(sizeof(unsigned int), > devfreq->profile->max_state, > devfreq->profile->max_state), > GFP_KERNEL); > if (!devfreq->trans_table) { > mutex_unlock(&devfreq->lock); > err = -ENOMEM; > - goto err_devfreq; > + goto err_dev; > } > > - devfreq->time_in_state = devm_kcalloc(&devfreq->dev, > - devfreq->profile->max_state, > - sizeof(unsigned long), > - GFP_KERNEL); > + devfreq->time_in_state = kcalloc(devfreq->profile->max_state, > + sizeof(unsigned long), > + GFP_KERNEL); > if (!devfreq->time_in_state) { > mutex_unlock(&devfreq->lock); > err = -ENOMEM; > - goto err_devfreq; > + goto err_dev; > } > > devfreq->last_stat_updated = jiffies; > > srcu_init_notifier_head(&devfreq->transition_notifier_list); > > + dev_set_name(&devfreq->dev, "devfreq%d", > + atomic_inc_return(&devfreq_no)); > + err = device_register(&devfreq->dev); > + if (err) { > + mutex_unlock(&devfreq->lock); > + put_device(&devfreq->dev); > + goto err_out; As per my comment on v5 I think the goto needs to go to 'err_dev'. The device registration failed, hence devfreq_dev_release() won't be called to free allocated memory. > + } > + > mutex_unlock(&devfreq->lock); > > mutex_lock(&devfreq_list_lock); > > governor = try_then_request_governor(devfreq->governor_name); > @@ -733,14 +734,20 @@ struct devfreq *devfreq_add_device(struct device *dev, > > return devfreq; > > err_init: > mutex_unlock(&devfreq_list_lock); > -err_devfreq: > devfreq_remove_device(devfreq); > - devfreq = NULL; > + return ERR_PTR(err); > + > err_dev: > + /* > + * Cleanup path for errors that happen before registration. > + * Otherwise we rely on devfreq_dev_release nit: add a period at the end of the second sentence. > + */ > + kfree(devfreq->time_in_state); > + kfree(devfreq->trans_table); > kfree(devfreq); > err_out: > return ERR_PTR(err); > } > EXPORT_SYMBOL(devfreq_add_device);