cpufreq: Drop policy locking from cpufreq_policy_is_good_for_eas()

Policy locking was added to cpufreq_policy_is_good_for_eas() by commit
4854649b1fb4 ("cpufreq/sched: Move cpufreq-specific EAS checks to
cpufreq") to address a theoretical race condition, but it turned out to
introduce a circular locking dependency between the policy rwsem and
sched_domains_mutex via cpuset_mutex. This leads to a board lockup on
OdroidN2 that is based on the ARM64 Amlogic Meson SoC.

Drop the policy locking from cpufreq_policy_is_good_for_eas() to address
this issue.

Fixes: 4854649b1fb4 ("cpufreq/sched: Move cpufreq-specific EAS checks to cpufreq")
Closes: https://lore.kernel.org/linux-pm/1bf3df62-0641-459f-99fc-fd511e564b84@samsung.com/
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/2806514.mvXUDI8C0e@rjwysocki.net

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 731ecfc..be727da 100644 (file)
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -3067,8 +3067,6 @@ static bool cpufreq_policy_is_good_for_eas(unsigned int cpu)
                return false;
        }
 
-       guard(cpufreq_policy_read)(policy);
-
        return sugov_is_governor(policy);
 }