diff --git a/[refs] b/[refs]
index bc702fde0005..d5e516062259 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 9a8b4584065dd241d6c2bf818e349986bd900b8e
+refs/heads/master: 3f902886a81c6d4e6c399760936b645b5c7a7342
diff --git a/trunk/arch/parisc/kernel/irq.c b/trunk/arch/parisc/kernel/irq.c
index f7ae2bcd49a5..21a9c5ad580b 100644
--- a/trunk/arch/parisc/kernel/irq.c
+++ b/trunk/arch/parisc/kernel/irq.c
@@ -250,10 +250,11 @@ void do_cpu_irq_mask(struct pt_regs *regs)
 	irq_enter();
 
 	/*
-	 * Only allow interrupt processing to be interrupted by the
-	 * timer tick
+	 * Don't allow TIMER or IPI nested interrupts.
+	 * Allowing any single interrupt to nest can lead to that CPU
+	 * handling interrupts with all enabled interrupts unmasked.
 	 */
-	set_eiem(EIEM_MASK(TIMER_IRQ));
+	set_eiem(0UL);
 
 	/* 1) only process IRQs that are enabled/unmasked (cpu_eiem)
 	 * 2) We loop here on EIRR contents in order to avoid
@@ -267,9 +268,6 @@ void do_cpu_irq_mask(struct pt_regs *regs)
 		if (!eirr_val)
 			break;
 
-		if (eirr_val & EIEM_MASK(TIMER_IRQ))
-			set_eiem(0);
-
 		mtctl(eirr_val, 23); /* reset bits we are going to process */
 
 		/* Work our way from MSb to LSb...same order we alloc EIRs */
@@ -283,7 +281,8 @@ void do_cpu_irq_mask(struct pt_regs *regs)
 			__do_IRQ(irq, regs);
 		}
 	}
-	set_eiem(cpu_eiem);
+
+	set_eiem(cpu_eiem);	/* restore original mask */
 	irq_exit();
 }