[PATCH 6.1 120/473] cpufreq: exit() callback is optional

Greg Kroah-Hartman
2024-06-06T14:14:03Z

From: Viresh Kumar <viresh.kumar@linaro.org>

[ Upstream commit b8f85833c05730d631576008daaa34096bc7f3ce ]

The exit() callback is optional and shouldn't be called without checking
a valid pointer first.

Also, we must clear freq_table pointer even if the exit() callback isn't
present.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Fixes: 91a12e91dc39 ("cpufreq: Allow light-weight tear down and bring up of CPUs")
Fixes: f339f3541701 ("cpufreq: Rearrange locking in cpufreq_remove_dev()")
Reported-by: Lizhe <sensor1010@163.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/cpufreq/cpufreq.c | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 91efa23e0e8f3..04d89cf0d71df 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1619,10 +1619,13 @@ static void __cpufreq_offline(unsigned int cpu, struct cpufreq_policy *policy)
*/
if (cpufreq_driver->offline) {
cpufreq_driver->offline(policy);
- } else if (cpufreq_driver->exit) {
- cpufreq_driver->exit(policy);
- policy->freq_table = NULL;
+ return;
}
+
+ if (cpufreq_driver->exit)
+ cpufreq_driver->exit(policy);
+
+ policy->freq_table = NULL;
}

static int cpufreq_offline(unsigned int cpu)
@@ -1680,7 +1683,7 @@ static void cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif)
}

/* We did light-weight exit earlier, do full tear down now */
- if (cpufreq_driver->offline)
+ if (cpufreq_driver->offline && cpufreq_driver->exit)
cpufreq_driver->exit(policy);

up_write(&policy->rwsem);
--
2.43.0