The cpu hotplug notifier gets called in both atomic and non-atomic contexts, it is not always safe to lock a mutex. Filter out all events except the six necessary ones, which are all sleepable, before taking the mutex.
Signed-off-by: Colin Cross <[email protected]> --- drivers/cpuidle/coupled.c | 12 ++++++++++++ 1 files changed, 12 insertions(+), 0 deletions(-) diff --git a/drivers/cpuidle/coupled.c b/drivers/cpuidle/coupled.c index 2c9bf26..c24dda0 100644 --- a/drivers/cpuidle/coupled.c +++ b/drivers/cpuidle/coupled.c @@ -678,6 +678,18 @@ static int cpuidle_coupled_cpu_notify(struct notifier_block *nb, int cpu = (unsigned long)hcpu; struct cpuidle_device *dev; + switch (action & ~CPU_TASKS_FROZEN) { + case CPU_UP_PREPARE: + case CPU_DOWN_PREPARE: + case CPU_ONLINE: + case CPU_DEAD: + case CPU_UP_CANCELED: + case CPU_DOWN_FAILED: + break; + default: + return NOTIFY_OK; + } + mutex_lock(&cpuidle_lock); dev = per_cpu(cpuidle_devices, cpu); -- 1.7.7.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
