From: Douglas Anderson dianders@chromium.org
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@vger.kernel.org Cc: Rafael J. Wysocki rafael.j.wysocki@intel.com Reviewed-by: Stephen Boyd swboyd@chromium.org Reviewed-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Douglas Anderson dianders@chromium.org Link: https://lore.kernel.org/r/20200504104917.v6.3.I2d44fc0053d019f239527a4e58294... Signed-off-by: Bjorn Andersson bjorn.andersson@linaro.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- 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);