diff options
| -rw-r--r-- | kernel/stop_machine.c | 22 | 
1 files changed, 22 insertions, 0 deletions
diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c index ba5070ce576..5b0951aa049 100644 --- a/kernel/stop_machine.c +++ b/kernel/stop_machine.c @@ -41,6 +41,7 @@ struct cpu_stopper {  };  static DEFINE_PER_CPU(struct cpu_stopper, cpu_stopper); +static bool stop_machine_initialized = false;  static void cpu_stop_init_done(struct cpu_stop_done *done, unsigned int nr_todo)  { @@ -386,6 +387,8 @@ static int __init cpu_stop_init(void)  	cpu_stop_cpu_callback(&cpu_stop_cpu_notifier, CPU_ONLINE, bcpu);  	register_cpu_notifier(&cpu_stop_cpu_notifier); +	stop_machine_initialized = true; +  	return 0;  }  early_initcall(cpu_stop_init); @@ -485,6 +488,25 @@ int __stop_machine(int (*fn)(void *), void *data, const struct cpumask *cpus)  					    .num_threads = num_online_cpus(),  					    .active_cpus = cpus }; +	if (!stop_machine_initialized) { +		/* +		 * Handle the case where stop_machine() is called +		 * early in boot before stop_machine() has been +		 * initialized. +		 */ +		unsigned long flags; +		int ret; + +		WARN_ON_ONCE(smdata.num_threads != 1); + +		local_irq_save(flags); +		hard_irq_disable(); +		ret = (*fn)(data); +		local_irq_restore(flags); + +		return ret; +	} +  	/* Set the initial state and stop all online cpus. */  	set_state(&smdata, STOPMACHINE_PREPARE);  	return stop_cpus(cpu_online_mask, stop_machine_cpu_stop, &smdata);  |