cpufreq: Fix policy initialization for internal governor drivers

Before commit 1e4f63aecb53 ("cpufreq: Avoid creating excessively
large stack frames") the initial value of the policy field in struct
cpufreq_policy set by the driver's ->init() callback was implicitly
passed from cpufreq_init_policy() to cpufreq_set_policy() if the
default governor was neither "performance" nor "powersave".  After
that commit, however, cpufreq_init_policy() must take that case into
consideration explicitly and handle it as appropriate, so make that
happen.

Fixes: 1e4f63aecb53 ("cpufreq: Avoid creating excessively large stack frames")
Link: https://lore.kernel.org/linux-pm/39fb762880c27da110086741315ca8b111d781cd.camel@gmail.com/
Reported-by: Artem Bityutskiy <dedekind1@gmail.com>
Cc: 5.4+ <stable@vger.kernel.org> # 5.4+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index cbe6c94..808874b 100644 (file)
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1076,9 +1076,17 @@ static int cpufreq_init_policy(struct cpufreq_policy *policy)
                        pol = policy->last_policy;
                } else if (def_gov) {
                        pol = cpufreq_parse_policy(def_gov->name);
-               } else {
-                       return -ENODATA;
+                       /*
+                        * In case the default governor is neiter "performance"
+                        * nor "powersave", fall back to the initial policy
+                        * value set by the driver.
+                        */
+                       if (pol == CPUFREQ_POLICY_UNKNOWN)
+                               pol = policy->policy;
                }
+               if (pol != CPUFREQ_POLICY_PERFORMANCE &&
+                   pol != CPUFREQ_POLICY_POWERSAVE)
+                       return -ENODATA;
        }
 
        return cpufreq_set_policy(policy, gov, pol);