From e3d7a89371090cfa284fe868b669a1d1182e3071 Mon Sep 17 00:00:00 2001
From: Sebastian Andrzej Siewior <>
Date: Thu, 23 Jan 2014 14:45:59 +0100
Subject: [PATCH 130/166] leds: trigger: Disable CPU trigger on PREEMPT_RT

The CPU trigger is invoked on ARM from CPU-idle. That trigger later
invokes led_trigger_event() which may invoke the callback of the actual driver.
That driver can acquire a spinlock_t which is okay on kernel without
PREEMPT_RT. On PREEMPT_RT enabled kernel this lock is turned into a sleeping
lock and must not be acquired with disabled interrupts.

Disable the CPU trigger on PREEMPT_RT.

Signed-off-by: Sebastian Andrzej Siewior <>
 drivers/leds/trigger/Kconfig |    1 +
 1 file changed, 1 insertion(+)

Index: linux-5.15.13-rt26/drivers/leds/trigger/Kconfig
@ linux-5.15.13-rt26/drivers/leds/trigger/Kconfig:67 @ config LEDS_TRIGGER_BACKLIGHT
 	bool "LED CPU Trigger"
+	depends on !PREEMPT_RT
 	  This allows LEDs to be controlled by active CPUs. This shows
 	  the active CPUs across an array of LEDs so you can see which