3.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Daniel Fu <danifu@xxxxxxxxxx> commit 3b9c10e98021e1f92e6f8c7ce1778b86ba68db10 upstream. If the current CPU has no cpuidle driver, drv will be NULL in cpuidle_driver_ref(). Check if that is the case before trying to bump up the driver's refcount to prevent the kernel from crashing. [rjw: Subject and changelog] Signed-off-by: Daniel Fu <danifu@xxxxxxxxxx> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> Cc: Mark Brown <broonie@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/cpuidle/driver.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/cpuidle/driver.c +++ b/drivers/cpuidle/driver.c @@ -251,7 +251,8 @@ struct cpuidle_driver *cpuidle_driver_re spin_lock(&cpuidle_driver_lock); drv = cpuidle_get_driver(); - drv->refcnt++; + if (drv) + drv->refcnt++; spin_unlock(&cpuidle_driver_lock); return drv; -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html