From: Douglas Anderson <dianders@xxxxxxxxxxxx> commit b5945214b76a1f22929481724ffd448000ede914 upstream. cpu_pm_notify() is basically a wrapper of notifier_call_chain(). notifier_call_chain() doesn't initialize *nr_calls to 0 before it starts incrementing it--presumably it's up to the callers to do this. Unfortunately the callers of cpu_pm_notify() don't init *nr_calls. This potentially means you could get too many or two few calls to CPU_PM_ENTER_FAILED or CPU_CLUSTER_PM_ENTER_FAILED depending on the luck of the stack. Let's fix this. Fixes: ab10023e0088 ("cpu_pm: Add cpu power management notifiers") Cc: stable@xxxxxxxxxxxxxxx Cc: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> Reviewed-by: Stephen Boyd <swboyd@xxxxxxxxxxxx> Reviewed-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx> Link: https://lore.kernel.org/r/20200504104917.v6.3.I2d44fc0053d019f239527a4e5829416714b7e299@changeid Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- kernel/cpu_pm.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/kernel/cpu_pm.c +++ b/kernel/cpu_pm.c @@ -89,7 +89,7 @@ EXPORT_SYMBOL_GPL(cpu_pm_unregister_noti */ int cpu_pm_enter(void) { - int nr_calls; + int nr_calls = 0; int ret = 0; ret = cpu_pm_notify(CPU_PM_ENTER, -1, &nr_calls); @@ -140,7 +140,7 @@ EXPORT_SYMBOL_GPL(cpu_pm_exit); */ int cpu_cluster_pm_enter(void) { - int nr_calls; + int nr_calls = 0; int ret = 0; ret = cpu_pm_notify(CPU_CLUSTER_PM_ENTER, -1, &nr_calls);