From: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Date: Wed, 26 Feb 2020 22:39:27 +0100
Subject: cpufreq: Fix policy initialization for internal governor drivers
Git-commit: f5739cb0b56590d68d8df8a44659893b6d0084c3
Patch-mainline: v5.6-rc4
References: bsc#1168476
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>
Signed-off-by: Mian Yousaf Kaukab <ykaukab@suse.de>
---
drivers/cpufreq/cpufreq.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index cbe6c94bf158..808874bccf4a 100644
--- 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);
--
2.16.4