--- kernel/smp.c

+++ kernel/smp.c

@@ -193,24 +193,6 @@ void generic_smp_call_function_interrupt

list_for_each_entry_rcu(data, &call_function.queue, csd.list) {

int refs;

- /*

- * Since we walk the list without any locks, we might

- * see an entry that was completed, removed from the

- * list and is in the process of being reused.

- *

- * We must check that the cpu is in the cpumask before

- * checking the refs, and both must be set before

- * executing the callback on this cpu.

- */

-

- if (!cpumask_test_cpu(cpu, data->cpumask))

- continue;

-

- smp_rmb();

-

- if (atomic_read(&data->refs) == 0)

- continue;

-

if (!cpumask_test_and_clear_cpu(cpu, data->cpumask))

continue;

@@ -219,8 +201,6 @@ void generic_smp_call_function_interrupt

refs = atomic_dec_return(&data->refs);

WARN_ON(refs < 0);

if (!refs) {

- WARN_ON(!cpumask_empty(data->cpumask));

-

spin_lock(&call_function.lock);

list_del_rcu(&data->csd.list);

spin_unlock(&call_function.lock);

@@ -421,21 +401,11 @@ void smp_call_function_many(const struct

data = &__get_cpu_var(cfd_data);

csd_lock(&data->csd);

- BUG_ON(atomic_read(&data->refs) || !cpumask_empty(data->cpumask));

data->csd.func = func;

data->csd.info = info;

cpumask_and(data->cpumask, mask, cpu_online_mask);

cpumask_clear_cpu(this_cpu, data->cpumask);

-

- /*

- * To ensure the interrupt handler gets an complete view

- * we order the cpumask and refs writes and order the read

- * of them in the interrupt handler. In addition we may

- * only clear our own cpu bit from the mask.

- */

- smp_wmb();

-

atomic_set(&data->refs, cpumask_weight(data->cpumask));

spin_lock_irqsave(&call_function.lock, flags);