[PATCH] ppc: fix idle with interrupts disabled

The idle-thread-preemption-fix.patch in mm1/2 leads to a stalled box on PPC
machines which do not provide a powersave function and therefor poll the
idle loop with interrupts disabled.  The patch reenables interrupts.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/ppc/kernel/idle.c

@@ -41,15 +41,18 @@ void default_idle(void)
 	if (!need_resched()) {
 		if (powersave != NULL)
 			powersave();
-#ifdef CONFIG_SMP
 		else {
+#ifdef CONFIG_SMP
 			set_thread_flag(TIF_POLLING_NRFLAG);
+			local_irq_enable();
 			while (!need_resched())
 				barrier();
 			clear_thread_flag(TIF_POLLING_NRFLAG);
-		}
+#else
+			local_irq_enable();
 #endif
 		}
+	}
 	if (need_resched())
 		schedule();
 }