diff --git a/arch/powerpc/platforms/powermac/pic.c b/arch/powerpc/platforms/powermac/pic.c
index 6f4f8b060def53cc1afc55b80ffd3f230766bb81..9815463450331686134219814663e091b0763d93 100644
--- a/arch/powerpc/platforms/powermac/pic.c
+++ b/arch/powerpc/platforms/powermac/pic.c
@@ -258,13 +258,14 @@ static unsigned int pmac_pic_get_irq(void)
 #ifdef CONFIG_XMON
 static struct irqaction xmon_action = {
 	.handler	= xmon_irq,
-	.flags		= 0,
+	.flags		= IRQF_NO_THREAD,
 	.name		= "NMI - XMON"
 };
 #endif
 
 static struct irqaction gatwick_cascade_action = {
 	.handler	= gatwick_action,
+	.flags		= IRQF_NO_THREAD,
 	.name		= "cascade",
 };