Make sure that the processor is actually online or die spectacularly.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/kernel/smp.c b/arch/mips/kernel/smp.c
index 2576291..798fce5 100644
--- a/arch/mips/kernel/smp.c
+++ b/arch/mips/kernel/smp.c
@@ -142,6 +142,11 @@
 	int i, cpus = num_online_cpus() - 1;
 	int cpu = smp_processor_id();
 
+	/*
+	 * Can die spectacularly if this CPU isn't yet marked online
+	 */
+	BUG_ON(!cpu_online(cpu));
+
 	if (!cpus)
 		return 0;