--- old_linux/arch/ppc/kernel/ppc4xx_pic.c	Thu Jan 31 15:05:03 2002
+++ linux/arch/ppc/kernel/ppc4xx_pic.c	Thu Jan 31 14:58:11 2002
@@ -135,11 +135,14 @@
 {
 	int bit, word;

-	bit = irq & 0x1f;
-	word = irq >> 5;
+	if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS))) {

-	ppc_cached_irq_mask[word] |= 1 << (31 - bit);
-	mtdcr(DCRN_UIC0_ER, ppc_cached_irq_mask[word]);
+		bit = irq & 0x1f;
+		word = irq >> 5;
+
+		ppc_cached_irq_mask[word] |= 1 << (31 - bit);
+		mtdcr(DCRN_UIC0_ER, ppc_cached_irq_mask[word]);
+	}
 }

 static void