unsigned long mask = cpumask_bits(cpumask)[0];
unsigned long flags;
+ if (WARN_ONCE(!mask, "empty IPI mask"))
+ return;
+
local_irq_save(flags);
WARN_ON(mask & ~cpumask_bits(cpu_online_mask)[0]);
__default_send_IPI_dest_field(mask, vector, apic->dest_logical);