diff options
Diffstat (limited to 'drivers/cpuidle/cpuidle-powernv.c')
| -rw-r--r-- | drivers/cpuidle/cpuidle-powernv.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/drivers/cpuidle/cpuidle-powernv.c b/drivers/cpuidle/cpuidle-powernv.c index 370593006f5f..cda8f62d555b 100644 --- a/drivers/cpuidle/cpuidle-powernv.c +++ b/drivers/cpuidle/cpuidle-powernv.c @@ -175,6 +175,24 @@ static int powernv_cpuidle_driver_init(void) drv->state_count += 1; } + /* + * On the PowerNV platform cpu_present may be less than cpu_possible in + * cases when firmware detects the CPU, but it is not available to the + * OS. If CONFIG_HOTPLUG_CPU=n, then such CPUs are not hotplugable at + * run time and hence cpu_devices are not created for those CPUs by the + * generic topology_init(). + * + * drv->cpumask defaults to cpu_possible_mask in + * __cpuidle_driver_init(). This breaks cpuidle on PowerNV where + * cpu_devices are not created for CPUs in cpu_possible_mask that + * cannot be hot-added later at run time. + * + * Trying cpuidle_register_device() on a CPU without a cpu_device is + * incorrect, so pass a correct CPU mask to the generic cpuidle driver. + */ + + drv->cpumask = (struct cpumask *)cpu_present_mask; + return 0; } |