consider such situation, current user_policy.min is 1000000,
current user_policy.max is 1200000, in cpufreq_set_policy,
other driver may update policy.min to 1200000, policy.max to
1300000. After that, If we input "echo 1300000 > scaling_min_freq",
then user_policy.min will be 1300000, and user_policy.max is
still 1200000, because the input value is checked with policy.max
not user_policy.max. if we get all related cpus offline and
online again, it will cause cpufreq_init_policy fail because
user_policy.min is higher than user_policy.max.

The solution is when user space tries to write scaling_(max|min)_freq,
the min/max of new_policy should be reinitialized with min/max
of user_policy, like what cpufreq_update_policy does.

Signed-off-by: Kevin Wangtao <kevin.wang...@hisilicon.com>
---
 drivers/cpufreq/cpufreq.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index b79c532..8b33e08 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -697,6 +697,8 @@ static ssize_t store_##file_name                            
        \
        struct cpufreq_policy new_policy;                               \
                                                                        \
        memcpy(&new_policy, policy, sizeof(*policy));                   \
+       new_policy->min = policy->user_policy.min;                      \
+       new_policy->max = policy->user_policy.max;                      \
                                                                        \
        ret = sscanf(buf, "%u", &new_policy.object);                    \
        if (ret != 1)                                                   \
-- 
2.8.1

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