[PATCH V4 03/10] PM / OPP: Don't use OPP structure outside of rcu protected section
From: Viresh Kumar <viresh.kumar@linaro.org>
Date: 2016-11-24 11:36:46
Also in:
linux-pm, lkml
Subsystem:
driver core, kobjects, debugfs and sysfs, hibernation (aka software suspend, aka swsusp), power management core, suspend to ram, the rest · Maintainers:
Greg Kroah-Hartman, "Rafael J. Wysocki", Danilo Krummrich, Linus Torvalds
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@linaro.org> Tested-by: Dave Gerlach <redacted> --- 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