From a054394c2592fa0d44a168b3af0c9a1352468cd9 Mon Sep 17 00:00:00 2001
From: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Date: Thu, 30 Apr 2009 15:08:47 -0700
Subject: [PATCH] --- yaml --- r: 144367 b: refs/heads/master c:
 08a42e86bce511b45ca3eee40f51674b02a777d1 h: refs/heads/master i:   144365:
 49c33fccdc01969b9938f456422cbcc8d3c986b1   144363:
 eeccf3afce2b41d0e8cf3cf638d0154f49b7c2fe   144359:
 a99982bc8c0ffabb944c9e7bf6cbca29575df263   144351:
 b3b302e136f55fcd61b734525314e531dec024c1 v: v3

---
 [refs]                                 |  2 +-
 trunk/arch/alpha/include/asm/uaccess.h |  2 ++
 trunk/arch/alpha/mm/extable.c          | 40 +++++++++++++++++++++++++-
 3 files changed, 42 insertions(+), 2 deletions(-)

diff --git a/[refs] b/[refs]
index b7674e6511c0..63a5a3163fbe 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 1ffb1c0c64b4a2b75eed1f63cc47f2beb711c92f
+refs/heads/master: 08a42e86bce511b45ca3eee40f51674b02a777d1
diff --git a/trunk/arch/alpha/include/asm/uaccess.h b/trunk/arch/alpha/include/asm/uaccess.h
index 163f3053001c..b49ec2f8d6e3 100644
--- a/trunk/arch/alpha/include/asm/uaccess.h
+++ b/trunk/arch/alpha/include/asm/uaccess.h
@@ -507,5 +507,7 @@ struct exception_table_entry
 	(pc) + (_fixup)->fixup.bits.nextinsn;			\
 })
 
+#define ARCH_HAS_SORT_EXTABLE
+#define ARCH_HAS_SEARCH_EXTABLE
 
 #endif /* __ALPHA_UACCESS_H */
diff --git a/trunk/arch/alpha/mm/extable.c b/trunk/arch/alpha/mm/extable.c
index dc7aeda15773..62dc379d301a 100644
--- a/trunk/arch/alpha/mm/extable.c
+++ b/trunk/arch/alpha/mm/extable.c
@@ -3,11 +3,49 @@
  */
 
 #include <linux/module.h>
+#include <linux/sort.h>
 #include <asm/uaccess.h>
 
+static inline unsigned long ex_to_addr(const struct exception_table_entry *x)
+{
+	return (unsigned long)&x->insn + x->insn;
+}
+
+static void swap_ex(void *a, void *b, int size)
+{
+	struct exception_table_entry *ex_a = a, *ex_b = b;
+	unsigned long addr_a = ex_to_addr(ex_a), addr_b = ex_to_addr(ex_b);
+	unsigned int t = ex_a->fixup.unit;
+
+	ex_a->fixup.unit = ex_b->fixup.unit;
+	ex_b->fixup.unit = t;
+	ex_a->insn = (int)(addr_b - (unsigned long)&ex_a->insn);
+	ex_b->insn = (int)(addr_a - (unsigned long)&ex_b->insn);
+}
+
+/*
+ * The exception table needs to be sorted so that the binary
+ * search that we use to find entries in it works properly.
+ * This is used both for the kernel exception table and for
+ * the exception tables of modules that get loaded.
+ */
+static int cmp_ex(const void *a, const void *b)
+{
+	const struct exception_table_entry *x = a, *y = b;
+
+	/* avoid overflow */
+	if (ex_to_addr(x) > ex_to_addr(y))
+		return 1;
+	if (ex_to_addr(x) < ex_to_addr(y))
+		return -1;
+	return 0;
+}
+
 void sort_extable(struct exception_table_entry *start,
 		  struct exception_table_entry *finish)
 {
+	sort(start, finish - start, sizeof(struct exception_table_entry),
+	     cmp_ex, swap_ex);
 }
 
 const struct exception_table_entry *
@@ -20,7 +58,7 @@ search_extable(const struct exception_table_entry *first,
 		unsigned long mid_value;
 
 		mid = (last - first) / 2 + first;
-		mid_value = (unsigned long)&mid->insn + mid->insn;
+		mid_value = ex_to_addr(mid);
                 if (mid_value == value)
                         return mid;
                 else if (mid_value < value)