summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--Documentation/cpu-freq/user-guide.txt5
-rw-r--r--drivers/cpufreq/cpufreq.c5
2 files changed, 9 insertions, 1 deletions
diff --git a/Documentation/cpu-freq/user-guide.txt b/Documentation/cpu-freq/user-guide.txt
index 7fedc00c3d30..555c8cf3650a 100644
--- a/Documentation/cpu-freq/user-guide.txt
+++ b/Documentation/cpu-freq/user-guide.txt
@@ -153,10 +153,13 @@ scaling_governor, and by "echoing" the name of another
that some governors won't load - they only
work on some specific architectures or
processors.
-scaling_min_freq and
+scaling_min_freq and
scaling_max_freq show the current "policy limits" (in
kHz). By echoing new values into these
files, you can change these limits.
+ NOTE: when setting a policy you need to
+ first set scaling_max_freq, then
+ scaling_min_freq.
If you have selected the "userspace" governor which allows you to
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index bc1088d9b379..ad996c772c8b 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1343,6 +1343,11 @@ static int __cpufreq_set_policy(struct cpufreq_policy *data, struct cpufreq_poli
memcpy(&policy->cpuinfo, &data->cpuinfo, sizeof(struct cpufreq_cpuinfo));
+ if (policy->min > data->min && policy->min > policy->max) {
+ ret = -EINVAL;
+ goto error_out;
+ }
+
/* verify the cpu speed can be set within this limit */
ret = cpufreq_driver->verify(policy);
if (ret)
OpenPOWER on IntegriCloud