When rpm_resume() desactivates the autosuspend timer, it should only try to cancel hrtimer but not wait for the handler to finish because both rpm_resume() and pm_suspend_timer_fn() are taking the power.lock. We can have the deadlock sequence: CPU0 CPU1 rpm_resume() spin_lock_irqsave pm_suspend_timer_fn() spin_lock_irqsave pm_runtime_deactivate_timer() hrtimer_cancel()
hrtimer_try_to_cancel() is enough because dev->power.timer_expires is also set to 0. Fixes: 8234f6734c5d ("PM-runtime: Switch autosuspend over to using hrtimers") Reported-by: Sunzhaosheng Sun(Zhaosheng) <sunzhaosh...@hisilicon.com> Signed-off-by: Vincent Guittot <vincent.guit...@linaro.org> --- drivers/base/power/runtime.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index 04407d9..78937c4 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -121,7 +121,7 @@ EXPORT_SYMBOL_GPL(pm_runtime_suspended_time); static void pm_runtime_deactivate_timer(struct device *dev) { if (dev->power.timer_expires > 0) { - hrtimer_cancel(&dev->power.suspend_timer); + hrtimer_try_to_cancel(&dev->power.suspend_timer); dev->power.timer_expires = 0; } } -- 2.7.4