[PATCH RT 05/15] PM / CPU: replace raw_notifier with atomic_notifier (fixup)
From: Steven Rostedt <rostedt@goodmis.org>
Date: 2017-12-02 00:04:39
Also in:
lkml
Subsystem:
the rest · Maintainer:
Linus Torvalds
4.9.65-rt57-rc2 stable review patch. If anyone has any objections, please let me know. ------------------ From: Sebastian Andrzej Siewior <bigeasy@linutronix.de> The original patch changed betwen its posting and what finally went into Rafael's tree so here is the delta. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> --- kernel/cpu_pm.c | 7 +++++++ 1 file changed, 7 insertions(+)
diff --git a/kernel/cpu_pm.c b/kernel/cpu_pm.c
index 10f4640f991e..67b02e138a47 100644
--- a/kernel/cpu_pm.c
+++ b/kernel/cpu_pm.c@@ -28,8 +28,15 @@ static int cpu_pm_notify(enum cpu_pm_event event, int nr_to_call, int *nr_calls) { int ret; + /* + * __atomic_notifier_call_chain has a RCU read critical section, which + * could be disfunctional in cpu idle. Copy RCU_NONIDLE code to let + * RCU know this. + */ + rcu_irq_enter_irqson(); ret = __atomic_notifier_call_chain(&cpu_pm_notifier_chain, event, NULL, nr_to_call, nr_calls); + rcu_irq_exit_irqson(); return notifier_to_errno(ret); }
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2.13.2