linux-toradex.git/drivers/thermal/cpu_cooling.c, branch v4.4.90

thermal: cpu_cooling: Avoid accessing potentially freed structures

2017-07-27T22:06:02+00:00

commit 289d72afddf83440117c35d864bf0c6309c1d011 upstream.

After the lock is dropped, it is possible that the cpufreq_dev gets
freed before we call get_level() and that can cause kernel to crash.

Drop the lock after we are done using the structure.

Fixes: 02373d7c69b4 ("thermal: cpu_cooling: fix lockdep problems in cpu_cooling")
Signed-off-by: Viresh Kumar 
Reviewed-by: Lukasz Luba 
Tested-by: Lukasz Luba 
Signed-off-by: Eduardo Valentin 
Signed-off-by: Greg Kroah-Hartman

thermal: cpu_cooling: fix improper order during initialization

2016-07-27T16:47:29+00:00

commit f840ab18bdf2e415dac21d09fbbbd2873111bd48 upstream.

The freq_table array is not populated before calling
thermal_of_cooling_register. The code which populates the freq table was
introduced in commit f6859014.
This should be done before registering new thermal cooling device.
The log shows effects of this wrong decision.
[    2.172614] cpu cpu1: Failed to get voltage for frequency 1984518656000: -34
[    2.220863] cpu cpu0: Failed to get voltage for frequency 1984524416000: -34

Fixes: f6859014c7e7 ("thermal: cpu_cooling: Store frequencies in descending order")
Signed-off-by: Lukasz Luba 
Acked-by: Javi Merino 
Acked-by: Viresh Kumar 
Signed-off-by: Zhang Rui 
Signed-off-by: Greg Kroah-Hartman

thermal: cpu_cooling: fix out of bounds access in time_in_idle

2016-03-09T23:34:56+00:00

commit a53b8394ec3c67255928df6ee9cc99dd1cd452e3 upstream.

In __cpufreq_cooling_register() we allocate the arrays for time_in_idle
and time_in_idle_timestamp to be as big as the number of cpus in this
cpufreq device.  However, in get_load() we access this array using the
cpu number as index, which can result in an out of bound access.

Index time_in_idle{,_timestamp} using the index in the cpufreq_device's
allowed_cpus mask, as we do for the load_cpu array in
cpufreq_get_requested_power()

Reported-by: Nicolas Boichat 
Cc: Amit Daniel Kachhap 
Cc: Zhang Rui 
Cc: Eduardo Valentin 
Tested-by: Nicolas Boichat 
Acked-by: Viresh Kumar 
Signed-off-by: Javi Merino 
Signed-off-by: Eduardo Valentin 
Signed-off-by: Greg Kroah-Hartman

thermal: cpu_cooling: Remove usage of devm functions

2015-10-10T03:32:21+00:00

In the function cpufreq_get_requested_power, the memory allocated
for load_cpu is live within the function only. And after the
allocation it is immediately freed with devm_kfree. There is no
need to allocate memory for load_cpu with devm function so replace
devm_kcalloc with kcalloc and devm_kfree with kfree.

Signed-off-by: Vaishali Thakkar 
Acked-by: Viresh Kumar 
Acked-by: Javi Merino 
Signed-off-by: Zhang Rui

thermal: cpu_cooling: free power table on error or when unregistering

2015-09-14T03:34:05+00:00

The power table is not being freed on error from cpufreq_cooling
register or when unregistering.  Free it.

Fixes: c36cf0717631 ("thermal: cpu_cooling: implement the power cooling device API")
Cc: Zhang Rui 
Cc: Eduardo Valentin 
Signed-off-by: Javi Merino 
Signed-off-by: Eduardo Valentin

thermal: cpu_cooling: don't call kcalloc() under rcu_read_lock

2015-09-14T03:33:17+00:00

build_dyn_power_table() allocates the power table while holding
rcu_read_lock.  kcalloc using GFP_KERNEL may sleep, so it can't be
called in an RCU read-side path.

Move the rcu protection to the part of the function that really needs
it: the part that handles the dev_pm_opp pointer received from
dev_pm_opp_find_freq_ceil().  In the unlikely case that there is an OPP
added to the cpu while this function is running, return -EAGAIN.

Fixes: c36cf0717631 ("thermal: cpu_cooling: implement the power cooling device API")
Cc: Zhang Rui 
Cc: Eduardo Valentin 
Signed-off-by: Javi Merino 
Signed-off-by: Eduardo Valentin

thermal/cpu_cooling: update policy limits if clipped_freq < policy->max

2015-08-15T01:26:23+00:00

policy->max is the maximum allowed frequency defined by user and
clipped_freq is the maximum that thermal constraints allow.

If clipped_freq is lower than policy->max, then we need to readjust
policy->max.

But, if clipped_freq is greater than policy->max, we don't need to do
anything. We used to call cpufreq_verify_within_limits() in this case,
but it doesn't change anything in this case.

Lets skip this unnecessary call and write a comment that explains this.

Signed-off-by: Viresh Kumar 
Signed-off-by: Eduardo Valentin

thermal/cpu_cooling: rename max_freq as clipped_freq in notifier

2015-08-15T01:26:23+00:00

That's what it is for, lets name it properly.

Signed-off-by: Viresh Kumar 
Signed-off-by: Eduardo Valentin

thermal/cpu_cooling: rename cpufreq_val as clipped_freq

2015-08-15T01:26:22+00:00

That's what it is for, lets name it properly.

Signed-off-by: Viresh Kumar 
Signed-off-by: Eduardo Valentin

thermal/cpu_cooling: convert 'switch' block to 'if' block in notifier

2015-08-15T01:26:22+00:00

We just need to take care of single event here and there is no need to
increase indentation level of most of the code (which causes lines
longer that 80 columns to break).

Kill the switch block.

Signed-off-by: Viresh Kumar 
Signed-off-by: Eduardo Valentin