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devfreq: rk3399_dmc: Don't use OPP structures outside of RCU locks

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The OPP structures are abused to the best here, without understanding
how the OPP core and RCU locks work.

In short, the OPP pointer saved in 'rk3399_dmcfreq' can become invalid
under your nose, as the OPP core may free it.

Fix various abuses around OPP structures and calls.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Viresh Kumar 2016-12-05 08:53:52 +05:30 committed by Rafael J. Wysocki
parent d8323de3d4
commit e37d35082e
1 changed files with 5 additions and 6 deletions
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11
drivers/devfreq/rk3399_dmc.c
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@ -80,7 +80,6 @@ struct rk3399_dmcfreq {
struct regulator *vdd_center;
unsigned long rate, target_rate;
unsigned long volt, target_volt;
struct dev_pm_opp *curr_opp;
};
static int rk3399_dmcfreq_target(struct device *dev, unsigned long *freq,
@ -102,9 +101,6 @@ static int rk3399_dmcfreq_target(struct device *dev, unsigned long *freq,
target_rate = dev_pm_opp_get_freq(opp);
target_volt = dev_pm_opp_get_voltage(opp);
dmcfreq->rate = dev_pm_opp_get_freq(dmcfreq->curr_opp);
dmcfreq->volt = dev_pm_opp_get_voltage(dmcfreq->curr_opp);
rcu_read_unlock();
if (dmcfreq->rate == target_rate)
@ -165,7 +161,9 @@ static int rk3399_dmcfreq_target(struct device *dev, unsigned long *freq,
if (err)
dev_err(dev, "Cannot to set vol %lu uV\n", target_volt);
dmcfreq->curr_opp = opp;
dmcfreq->rate = target_rate;
dmcfreq->volt = target_volt;
out:
mutex_unlock(&dmcfreq->lock);
return err;
@ -430,8 +428,9 @@ static int rk3399_dmcfreq_probe(struct platform_device *pdev)
rcu_read_unlock();
return PTR_ERR(opp);
}
data->rate = dev_pm_opp_get_freq(opp);
data->volt = dev_pm_opp_get_voltage(opp);
rcu_read_unlock();
data->curr_opp = opp;
rk3399_devfreq_dmc_profile.initial_freq = data->rate;