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    SubjectRe: [patch 00/61] ANNOUNCE: lock validator -V1
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    > I'm feeling a bit overwhelmed by the voluminous output of this checker.
    > Especially as (directly at least) cpufreq doesn't touch vma's, or mmap's.

    the reporter doesn't have CONFIG_KALLSYMS_ALL enabled which gives
    sometimes misleading backtraces (should lockdep just enable KALLSYMS_ALL
    to get more useful bugreports?)

    the problem is this, there are 2 scenarios in this bug:

    One
    ---
    store_scaling_governor takes policy->lock and then calls __cpufreq_set_policy
    __cpufreq_set_policy calls __cpufreq_governor
    __cpufreq_governor calls __cpufreq_driver_target via cpufreq_governor_performance
    __cpufreq_driver_target calls lock_cpu_hotplug() (which takes the hotplug lock)


    Two
    ---
    cpufreq_stats_init lock_cpu_hotplug() and then calls cpufreq_stat_cpu_callback
    cpufreq_stat_cpu_callback calls cpufreq_update_policy
    cpufreq_update_policy takes the policy->lock


    so this looks like a real honest AB-BA deadlock to me...


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