intel_idle: Fix false positive RCU splats due to incorrect hardirqs s…

…tate

Commit 32d4fd5 ("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: 32d4fd5 ("cpuidle,intel_idle: Fix CPUIDLE_FLAG_IRQ_ENABLE")
Signed-off-by: Waiman Long <[email protected]>
Cc: 5.16+ <[email protected]> # 5.16+
Signed-off-by: Rafael J. Wysocki <[email protected]>

drivers/idle/intel_idle.c

@@ -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;
 }