From: Douglas Anderson <[email protected]>

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: [email protected]
Cc: Rafael J. Wysocki <[email protected]>
Reviewed-by: Stephen Boyd <[email protected]>
Reviewed-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Douglas Anderson <[email protected]>
Link: 
https://lore.kernel.org/r/20200504104917.v6.3.I2d44fc0053d019f239527a4e5829416714b7e299@changeid
Signed-off-by: Bjorn Andersson <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 kernel/cpu_pm.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/kernel/cpu_pm.c
+++ b/kernel/cpu_pm.c
@@ -80,7 +80,7 @@ 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);
@@ -131,7 +131,7 @@ 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);


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