diff --git a/arch/sparc64/kernel/smp.c b/arch/sparc64/kernel/smp.c
index 5d90ee9..8aca4b1 100644
--- a/arch/sparc64/kernel/smp.c
+++ b/arch/sparc64/kernel/smp.c
@@ -168,6 +168,9 @@
 		rmb();
 
 	cpu_set(cpuid, cpu_online_map);
+
+	/* idle thread is expected to have preempt disabled */
+	preempt_disable();
 }
 
 void cpu_panic(void)