From: Richard Cochran Date: Wed, 6 Apr 2016 21:00:51 +0000 (-0400) Subject: intel_idle: Fix deallocation order on the driver exit path. X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=51319918bcc31f901646fc66348d41cf74ee0566;p=openwrt%2Fstaging%2Fblogic.git intel_idle: Fix deallocation order on the driver exit path. In the module_exit() method, this driver first frees its per-CPU pointer, then unregisters a callback making use of the pointer. Furthermore, the function, intel_idle_cpuidle_devices_uninit, is racy against CPU hot plugging as it calls for_each_online_cpu(). This patch corrects the issues by unregistering first on the exit path while holding the hot plug lock. Signed-off-by: Richard Cochran Signed-off-by: Len Brown Signed-off-by: Rafael J. Wysocki --- diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c index cb85c4c42ff9..4a1de3dcbf85 100644 --- a/drivers/idle/intel_idle.c +++ b/drivers/idle/intel_idle.c @@ -1242,16 +1242,16 @@ static int __init intel_idle_init(void) static void __exit intel_idle_exit(void) { - intel_idle_cpuidle_devices_uninit(); - cpuidle_unregister_driver(&intel_idle_driver); - cpu_notifier_register_begin(); if (lapic_timer_reliable_states != LAPIC_TIMER_ALWAYS_RELIABLE) on_each_cpu(__setup_broadcast_timer, (void *)false, 1); __unregister_cpu_notifier(&cpu_hotplug_notifier); + intel_idle_cpuidle_devices_uninit(); cpu_notifier_register_done(); + + cpuidle_unregister_driver(&intel_idle_driver); } module_init(intel_idle_init);