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intel_idle: Fix false positive RCU splats due to incorrect hardirqs state

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Commit 32d4fd5751 ("cpuidle,intel_idle: Fix CPUIDLE_FLAG_IRQ_ENABLE")
uses raw_local_irq_enable/local_irq_disable() around call to
__intel_idle() in intel_idle_irq().

With interrupt enabled, timer tick interrupt can happen and a
subsequently call to __do_softirq() may change the lockdep hardirqs state
of a debug kernel back to 'on'. This will result in a mismatch between
the cpu hardirqs state (off) and the lockdep hardirqs state (on) causing
a number of false positive "WARNING: suspicious RCU usage" splats.

Fix that by using local_irq_disable() to disable interrupt in
intel_idle_irq().

Fixes: 32d4fd5751 ("cpuidle,intel_idle: Fix CPUIDLE_FLAG_IRQ_ENABLE")
Signed-off-by: Waiman Long <longman@redhat.com>
Cc: 5.16+ <stable@vger.kernel.org> # 5.16+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Waiman Long 2022-07-23 15:59:32 -04:00 committed by Rafael J. Wysocki
parent e0dccc3b76
commit d295ad34f2
1 changed files with 7 additions and 1 deletions
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8
drivers/idle/intel_idle.c
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@ -162,7 +162,13 @@ static __cpuidle int intel_idle_irq(struct cpuidle_device *dev,
raw_local_irq_enable();
ret = __intel_idle(dev, drv, index);
raw_local_irq_disable();
/*
* The lockdep hardirqs state may be changed to 'on' with timer
* tick interrupt followed by __do_softirq(). Use local_irq_disable()
* to keep the hardirqs state correct.
*/
local_irq_disable();
return ret;
}