From e4969ebac83fdea78d89c779331396728a4e6199 Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Thu, 11 Apr 2013 08:04:53 +0000 Subject: cpufreq: Call __cpufreq_governor() with correct policy->cpus mask __cpufreq_governor() must be called with a correct policy->cpus mask. In __cpufreq_remove_dev() we initially clear policy->cpus with cpumask_clear_cpu() and then call __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT). If the governor is doing some per-cpu stuff in EXIT callback, this can create uncertain behavior. Generic governors in drivers/cpufreq/ doesn't do any per-cpu stuff in EXIT callback and so we don't face any issues currently. But its better to keep the code clean, so we don't face any issues in future. Now, we call cpumask_clear_cpu() only when multiple cpus are managed by policy. Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/cpufreq.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'drivers/cpufreq') diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index fd97a620518d..3564947ea7ac 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -1105,7 +1105,9 @@ static int __cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif WARN_ON(lock_policy_rwsem_write(cpu)); cpus = cpumask_weight(data->cpus); - cpumask_clear_cpu(cpu, data->cpus); + + if (cpus > 1) + cpumask_clear_cpu(cpu, data->cpus); unlock_policy_rwsem_write(cpu); if (cpu != data->cpu) { -- cgit v1.2.3