[PATCH 4.14 151/159] cpuidle: fix broadcast control when broadcast can not be entered

Greg Kroah-Hartman
2017-12-22T09:14:08Z

From: Nicholas Piggin <npiggin@gmail.com>

[ Upstream commit f187851b9b4a76952b1158b86434563dd2031103 ]

When failing to enter broadcast timer mode for an idle state that
requires it, a new state is selected that does not require broadcast,
but the broadcast variable remains set. This causes
tick_broadcast_exit to be called despite not having entered broadcast
mode.

This causes the WARN_ON_ONCE(!irqs_disabled()) to trigger in some
cases. It does not appear to cause problems for code today, but seems
to violate the interface so should be fixed.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/cpuidle/cpuidle.c | 1 +
1 file changed, 1 insertion(+)

--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -208,6 +208,7 @@ int cpuidle_enter_state(struct cpuidle_d
return -EBUSY;
}
target_state = &drv->states[index];
+ broadcast = false;
}

/* Take note of the planned idle state. */