[PATCH] ARM: Move signal return code into vector page

Move the signal return code into the vector page instead of placing
it on the user mode stack, which will allow us to avoid flushing
the instruction cache on signals, as well as eventually allowing
non-exec stack.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/kernel/signal.h

@@ -0,0 +1,12 @@
+/*
+ *  linux/arch/arm/kernel/signal.h
+ *
+ *  Copyright (C) 2005 Russell King.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#define KERN_SIGRETURN_CODE	0xffff0500
+
+extern const unsigned long sigreturn_codes[4];