This broke after a recent change "cedb70a cpufreq: Split __cpufreq_remove_dev() into two parts" from Srivatsa..
Consider a scenario where we have two CPUs in a policy (0 & 1) and we are removing cpu 1. On the call to __cpufreq_remove_dev_prepare() we have cleared 1 from policy->cpus and now on a call to __cpufreq_remove_dev_finish() we read cpumask_weight of policy->cpus, which will come as 1 and this code will behave as if we are removing the last cpu from policy :)
Fix it by clearing cpu mask in __cpufreq_remove_dev_finish() instead of __cpufreq_remove_dev_prepare().
Signed-off-by: Viresh Kumar viresh.kumar@linaro.org --- drivers/cpufreq/cpufreq.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-)
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 0e11fcb..b556d46 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -1175,12 +1175,9 @@ static int __cpufreq_remove_dev_prepare(struct device *dev, policy->governor->name, CPUFREQ_NAME_LEN); #endif
- WARN_ON(lock_policy_rwsem_write(cpu)); + lock_policy_rwsem_read(cpu); cpus = cpumask_weight(policy->cpus); - - if (cpus > 1) - cpumask_clear_cpu(cpu, policy->cpus); - unlock_policy_rwsem_write(cpu); + unlock_policy_rwsem_read(cpu);
if (cpu != policy->cpu) { if (!frozen) @@ -1222,9 +1219,12 @@ static int __cpufreq_remove_dev_finish(struct device *dev, return -EINVAL; }
- lock_policy_rwsem_read(cpu); + WARN_ON(lock_policy_rwsem_write(cpu)); cpus = cpumask_weight(policy->cpus); - unlock_policy_rwsem_read(cpu); + + if (cpus > 1) + cpumask_clear_cpu(cpu, policy->cpus); + unlock_policy_rwsem_write(cpu);
/* If cpu is last user of policy, free policy */ if (cpus == 1) {