sh: Guard against early IPIs in flush_cache_all().
flush_cache_all() gets called in to when we do some early ioremapping.
Unfortunately on SDK7786 the interrupt controller itself requires
ioremapping, leading to a bit of a chicken and egg scenario. For now,
don't bother with IPI crosscalls if there aren't any other CPUs online.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/arch/sh/mm/cache.c b/arch/sh/mm/cache.c
index b8607fa..0f4095d 100644
--- a/arch/sh/mm/cache.c
+++ b/arch/sh/mm/cache.c
@@ -2,7 +2,7 @@
* arch/sh/mm/cache.c
*
* Copyright (C) 1999, 2000, 2002 Niibe Yutaka
- * Copyright (C) 2002 - 2009 Paul Mundt
+ * Copyright (C) 2002 - 2010 Paul Mundt
*
* Released under the terms of the GNU GPL v2.0.
*/
@@ -41,8 +41,17 @@
int wait)
{
preempt_disable();
- smp_call_function(func, info, wait);
+
+ /*
+ * It's possible that this gets called early on when IRQs are
+ * still disabled due to ioremapping by the boot CPU, so don't
+ * even attempt IPIs unless there are other CPUs online.
+ */
+ if (num_online_cpus() > 1)
+ smp_call_function(func, info, wait);
+
func(info);
+
preempt_enable();
}