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thermal: cpu_cooling: Fix NULL dereference in cpufreq_state2power 

Currently all CPU cooling devices share a
`struct thermal_cooling_device_ops` instance. The thermal core uses the
presence of functions in this struct to determine if a cooling device
has a power model (see cdev_is_power_actor). cpu_cooling.c adds the
power model functions to the shared struct when a device is registered
with a power model.

Therefore, if a CPU cooling device is registered using
[of_]cpufreq_power_cooling_register, _all_ devices will be determined to
have a power model, including any registered with
[of_]cpufreq_cooling_register. This can result in cpufreq_state2power
being called on a device where dyn_power_table is NULL.

With this commit, instead of having a shared thermal_cooling_device_ops
which is mutated, we have two versions: one with the power functions and
one without.

Signed-off-by: Brendan Jackman <brendan.jackman@arm.com>
Cc: Amit Daniel Kachhap <amit.kachhap@gmail.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Javi Merino <javi.merino@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
hifive-unleashed-5.1
Brendan Jackman 2016-08-17 16:14:59 +01:00 committed by Zhang Rui
parent 694d0d0bb2
commit a305a4387a
1 changed files with 16 additions and 5 deletions
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21
drivers/thermal/cpu_cooling.c
View File

@ -740,12 +740,22 @@ static int cpufreq_power2state(struct thermal_cooling_device *cdev,
}
/* Bind cpufreq callbacks to thermal cooling device ops */
static struct thermal_cooling_device_ops cpufreq_cooling_ops = {
.get_max_state = cpufreq_get_max_state,
.get_cur_state = cpufreq_get_cur_state,
.set_cur_state = cpufreq_set_cur_state,
};
static struct thermal_cooling_device_ops cpufreq_power_cooling_ops = {
.get_max_state = cpufreq_get_max_state,
.get_cur_state = cpufreq_get_cur_state,
.set_cur_state = cpufreq_set_cur_state,
.get_requested_power = cpufreq_get_requested_power,
.state2power = cpufreq_state2power,
.power2state = cpufreq_power2state,
};
/* Notifier for cpufreq policy change */
static struct notifier_block thermal_cpufreq_notifier_block = {
.notifier_call = cpufreq_thermal_notifier,
@ -795,6 +805,7 @@ __cpufreq_cooling_register(struct device_node *np,
struct cpumask temp_mask;
unsigned int freq, i, num_cpus;
int ret;
struct thermal_cooling_device_ops *cooling_ops;
cpumask_and(&temp_mask, clip_cpus, cpu_online_mask);
policy = cpufreq_cpu_get(cpumask_first(&temp_mask));
@ -850,10 +861,6 @@ __cpufreq_cooling_register(struct device_node *np,
cpumask_copy(&cpufreq_dev->allowed_cpus, clip_cpus);
if (capacitance) {
cpufreq_cooling_ops.get_requested_power =
cpufreq_get_requested_power;
cpufreq_cooling_ops.state2power = cpufreq_state2power;
cpufreq_cooling_ops.power2state = cpufreq_power2state;
cpufreq_dev->plat_get_static_power = plat_static_func;
ret = build_dyn_power_table(cpufreq_dev, capacitance);
@ -861,6 +868,10 @@ __cpufreq_cooling_register(struct device_node *np,
cool_dev = ERR_PTR(ret);
goto free_table;
}
cooling_ops = &cpufreq_power_cooling_ops;
} else {
cooling_ops = &cpufreq_cooling_ops;
}
ret = get_idr(&cpufreq_idr, &cpufreq_dev->id);
@ -885,7 +896,7 @@ __cpufreq_cooling_register(struct device_node *np,
cpufreq_dev->id);
cool_dev = thermal_of_cooling_device_register(np, dev_name, cpufreq_dev,
&cpufreq_cooling_ops);
cooling_ops);
if (IS_ERR(cool_dev))
goto remove_idr;