[PATCH v5 3/5] kernel/cpu_pm: Fix uninitted local in cpu_pm

From: Douglas Anderson
Date: Fri Apr 24 2020 - 12:47:46 EST


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")
Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
Reviewed-by: Stephen Boyd <swboyd@xxxxxxxxxxxx>
---

Changes in v5: None
Changes in v4: None
Changes in v3: None
Changes in v2:
- ("Fix uninitted local in cpu_pm") new for v2.

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

diff --git a/kernel/cpu_pm.c b/kernel/cpu_pm.c
index cbca6879ab7d..44a259338e33 100644
--- a/kernel/cpu_pm.c
+++ b/kernel/cpu_pm.c
@@ -80,7 +80,7 @@ EXPORT_SYMBOL_GPL(cpu_pm_unregister_notifier);
*/
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);
--
2.26.2.303.gf8c07b1a785-goog