[PATCH V2 2/8] PM / OPP: Don't use OPP structure outside of rcu protected section

From: Viresh Kumar
Date: Thu Oct 20 2016 - 04:46:03 EST


The OPP structure must not be used out of the rcu protected section.
Cache the values to be used in separate variables instead.

Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
---
drivers/base/power/opp/core.c | 16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/drivers/base/power/opp/core.c b/drivers/base/power/opp/core.c
index 4c7c6da7a989..056527a3fb4e 100644
--- a/drivers/base/power/opp/core.c
+++ b/drivers/base/power/opp/core.c
@@ -584,6 +584,7 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq)
struct clk *clk;
unsigned long freq, old_freq;
unsigned long u_volt, u_volt_min, u_volt_max;
+ unsigned long old_u_volt, old_u_volt_min, old_u_volt_max;
int ret;

if (unlikely(!target_freq)) {
@@ -633,6 +634,14 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq)
return ret;
}

+ if (IS_ERR(old_opp)) {
+ old_u_volt = 0;
+ } else {
+ old_u_volt = old_opp->u_volt;
+ old_u_volt_min = old_opp->u_volt_min;
+ old_u_volt_max = old_opp->u_volt_max;
+ }
+
u_volt = opp->u_volt;
u_volt_min = opp->u_volt_min;
u_volt_max = opp->u_volt_max;
@@ -677,9 +686,10 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq)
__func__, old_freq);
restore_voltage:
/* This shouldn't harm even if the voltages weren't updated earlier */
- if (!IS_ERR(old_opp))
- _set_opp_voltage(dev, reg, old_opp->u_volt,
- old_opp->u_volt_min, old_opp->u_volt_max);
+ if (old_u_volt) {
+ _set_opp_voltage(dev, reg, old_u_volt, old_u_volt_min,
+ old_u_volt_max);
+ }

return ret;
}
--
2.7.1.410.g6faf27b