Hello, In drivers/cpuidle/cpuidle.c, there are two functions cpuidle_install_idle_handler & cpuidle_uninstall_idle_handler. The names seem confusing to me as they don't install any handler, rather set 'initialized' variable to 1/0. In v3.0 kernel, these functions used to look as below where they installed and uninstalled some handler function - void cpuidle_install_idle_handler(void) 123 { 124 if (enabled_devices && (pm_idle != cpuidle_idle_call)) { 125 /* Make sure all changes finished before we switch to new idle */ 126 smp_wmb(); 127 pm_idle = cpuidle_idle_call; 128 } 129 } void cpuidle_uninstall_idle_handler(void) 135 { 136 if (enabled_devices && pm_idle_old && (pm_idle != pm_idle_old)) { 137 pm_idle = pm_idle_old; 138 cpuidle_kick_cpus(); 139 } 140 } Do these names (and corresponding comments) still hold? -- Thanks, -Meraj