diff options
Diffstat (limited to 'kernel/smp.c')
| -rw-r--r-- | kernel/smp.c | 40 |
1 files changed, 34 insertions, 6 deletions
diff --git a/kernel/smp.c b/kernel/smp.c index ad63d85..2accdf6 100644 --- a/kernel/smp.c +++ b/kernel/smp.c @@ -177,6 +177,11 @@ void generic_smp_call_function_interrupt(void) int cpu = get_cpu(); /* + * Shouldn't receive this interrupt on a cpu that is not yet online. + */ + WARN_ON_ONCE(!cpu_online(cpu)); + + /* * Ensure entry is visible on call_function_queue after we have * entered the IPI. See comment in smp_call_function_many. * If we don't have this, then we may miss an entry on the list @@ -230,6 +235,11 @@ void generic_smp_call_function_single_interrupt(void) unsigned int data_flags; LIST_HEAD(list); + /* + * Shouldn't receive this interrupt on a cpu that is not yet online. + */ + WARN_ON_ONCE(!cpu_online(smp_processor_id())); + spin_lock(&q->lock); list_replace_init(&q->list, &list); spin_unlock(&q->lock); @@ -285,8 +295,14 @@ int smp_call_function_single(int cpu, void (*func) (void *info), void *info, */ this_cpu = get_cpu(); - /* Can deadlock when called with interrupts disabled */ - WARN_ON_ONCE(irqs_disabled() && !oops_in_progress); + /* + * Can deadlock when called with interrupts disabled. + * We allow cpu's that are not yet online though, as no one else can + * send smp call function interrupt to this cpu and as such deadlocks + * can't happen. + */ + WARN_ON_ONCE(cpu_online(this_cpu) && irqs_disabled() + && !oops_in_progress); if (cpu == this_cpu) { local_irq_save(flags); @@ -329,8 +345,14 @@ void __smp_call_function_single(int cpu, struct call_single_data *data, { csd_lock(data); - /* Can deadlock when called with interrupts disabled */ - WARN_ON_ONCE(wait && irqs_disabled() && !oops_in_progress); + /* + * Can deadlock when called with interrupts disabled. + * We allow cpu's that are not yet online though, as no one else can + * send smp call function interrupt to this cpu and as such deadlocks + * can't happen. + */ + WARN_ON_ONCE(cpu_online(smp_processor_id()) && wait && irqs_disabled() + && !oops_in_progress); generic_exec_single(cpu, data, wait); } @@ -365,8 +387,14 @@ void smp_call_function_many(const struct cpumask *mask, unsigned long flags; int cpu, next_cpu, this_cpu = smp_processor_id(); - /* Can deadlock when called with interrupts disabled */ - WARN_ON_ONCE(irqs_disabled() && !oops_in_progress); + /* + * Can deadlock when called with interrupts disabled. + * We allow cpu's that are not yet online though, as no one else can + * send smp call function interrupt to this cpu and as such deadlocks + * can't happen. + */ + WARN_ON_ONCE(cpu_online(this_cpu) && irqs_disabled() + && !oops_in_progress); /* So, what's a CPU they want? Ignoring this one. */ cpu = cpumask_first_and(mask, cpu_online_mask); |
