Add the rt linux 4.1.3-rt3 as base

Import the rt linux 4.1.3-rt3 as OPNFV kvm base.

It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:

commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date:   Sat Jul 25 12:13:34 2015 +0200

    Prepare v4.1.3-rt3

    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.

Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>

1 files changed, 49 insertions, 0 deletions

diff --git a/kernel/arch/frv/mm/extable.c b/kernel/arch/frv/mm/extable.c
new file mode 100644
index 000000000..8863d6c1d
--- /dev/null
+++ b/kernel/arch/frv/mm/extable.c
@@ -0,0 +1,49 @@
+/*
+ * linux/arch/frv/mm/extable.c
+ */
+
+#include <linux/module.h>
+#include <linux/spinlock.h>
+#include <asm/uaccess.h>
+
+extern const void __memset_end, __memset_user_error_lr, __memset_user_error_handler;
+extern const void __memcpy_end, __memcpy_user_error_lr, __memcpy_user_error_handler;
+extern spinlock_t modlist_lock;
+
+
+/*****************************************************************************/
+/*
+ * see if there's a fixup handler available to deal with a kernel fault
+ */
+unsigned long search_exception_table(unsigned long pc)
+{
+	const struct exception_table_entry *extab;
+
+	/* determine if the fault lay during a memcpy_user or a memset_user */
+	if (__frame->lr == (unsigned long) &__memset_user_error_lr &&
+	    (unsigned long) &memset <= pc && pc < (unsigned long) &__memset_end
+	    ) {
+		/* the fault occurred in a protected memset
+		 * - we search for the return address (in LR) instead of the program counter
+		 * - it was probably during a clear_user()
+		 */
+		return (unsigned long) &__memset_user_error_handler;
+	}
+
+	if (__frame->lr == (unsigned long) &__memcpy_user_error_lr &&
+	    (unsigned long) &memcpy <= pc && pc < (unsigned long) &__memcpy_end
+	    ) {
+		/* the fault occurred in a protected memset
+		 * - we search for the return address (in LR) instead of the program counter
+		 * - it was probably during a copy_to/from_user()
+		 */
+		return (unsigned long) &__memcpy_user_error_handler;
+	}
+
+	extab = search_exception_tables(pc);
+	if (extab)
+		return extab->fixup;
+
+	return 0;
+
+} /* end search_exception_table() */