1 files changed, 28 insertions, 72 deletions

diff --git a/arch/x86/mm/extable.c b/arch/x86/mm/extable.c
index 9dd7e4b7fcde..903ec1e9c326 100644
--- a/arch/x86/mm/extable.c
+++ b/arch/x86/mm/extable.c
@@ -3,9 +3,6 @@
 #include <linux/sort.h>
 #include <asm/uaccess.h>
 
-typedef bool (*ex_handler_t)(const struct exception_table_entry *,
-			    struct pt_regs *, int);
-
 static inline unsigned long
 ex_insn_addr(const struct exception_table_entry *x)
 {
@@ -16,56 +13,11 @@ ex_fixup_addr(const struct exception_table_entry *x)
 {
 	return (unsigned long)&x->fixup + x->fixup;
 }
-static inline ex_handler_t
-ex_fixup_handler(const struct exception_table_entry *x)
-{
-	return (ex_handler_t)((unsigned long)&x->handler + x->handler);
-}
-
-bool ex_handler_default(const struct exception_table_entry *fixup,
-		       struct pt_regs *regs, int trapnr)
-{
-	regs->ip = ex_fixup_addr(fixup);
-	return true;
-}
-EXPORT_SYMBOL(ex_handler_default);
-
-bool ex_handler_fault(const struct exception_table_entry *fixup,
-		     struct pt_regs *regs, int trapnr)
-{
-	regs->ip = ex_fixup_addr(fixup);
-	regs->ax = trapnr;
-	return true;
-}
-EXPORT_SYMBOL_GPL(ex_handler_fault);
-
-bool ex_handler_ext(const struct exception_table_entry *fixup,
-		   struct pt_regs *regs, int trapnr)
-{
-	/* Special hack for uaccess_err */
-	current_thread_info()->uaccess_err = 1;
-	regs->ip = ex_fixup_addr(fixup);
-	return true;
-}
-EXPORT_SYMBOL(ex_handler_ext);
-
-bool ex_has_fault_handler(unsigned long ip)
-{
-	const struct exception_table_entry *e;
-	ex_handler_t handler;
-
-	e = search_exception_tables(ip);
-	if (!e)
-		return false;
-	handler = ex_fixup_handler(e);
-
-	return handler == ex_handler_fault;
-}
 
-int fixup_exception(struct pt_regs *regs, int trapnr)
+int fixup_exception(struct pt_regs *regs)
 {
-	const struct exception_table_entry *e;
-	ex_handler_t handler;
+	const struct exception_table_entry *fixup;
+	unsigned long new_ip;
 
 #ifdef CONFIG_PNPBIOS
 	if (unlikely(SEGMENT_IS_PNP_CODE(regs->cs))) {
@@ -81,34 +33,42 @@ int fixup_exception(struct pt_regs *regs, int trapnr)
 	}
 #endif
 
-	e = search_exception_tables(regs->ip);
-	if (!e)
-		return 0;
+	fixup = search_exception_tables(regs->ip);
+	if (fixup) {
+		new_ip = ex_fixup_addr(fixup);
+
+		if (fixup->fixup - fixup->insn >= 0x7ffffff0 - 4) {
+			/* Special hack for uaccess_err */
+			current_thread_info()->uaccess_err = 1;
+			new_ip -= 0x7ffffff0;
+		}
+		regs->ip = new_ip;
+		return 1;
+	}
 
-	handler = ex_fixup_handler(e);
-	return handler(e, regs, trapnr);
+	return 0;
 }
 
 /* Restricted version used during very early boot */
 int __init early_fixup_exception(unsigned long *ip)
 {
-	const struct exception_table_entry *e;
+	const struct exception_table_entry *fixup;
 	unsigned long new_ip;
-	ex_handler_t handler;
 
-	e = search_exception_tables(*ip);
-	if (!e)
-		return 0;
+	fixup = search_exception_tables(*ip);
+	if (fixup) {
+		new_ip = ex_fixup_addr(fixup);
 
-	new_ip  = ex_fixup_addr(e);
-	handler = ex_fixup_handler(e);
+		if (fixup->fixup - fixup->insn >= 0x7ffffff0 - 4) {
+			/* uaccess handling not supported during early boot */
+			return 0;
+		}
 
-	/* special handling not supported during early boot */
-	if (handler != ex_handler_default)
-		return 0;
+		*ip = new_ip;
+		return 1;
+	}
 
-	*ip = new_ip;
-	return 1;
+	return 0;
 }
 
 /*
@@ -173,8 +133,6 @@ void sort_extable(struct exception_table_entry *start,
 		i += 4;
 		p->fixup += i;
 		i += 4;
-		p->handler += i;
-		i += 4;
 	}
 
 	sort(start, finish - start, sizeof(struct exception_table_entry),
@@ -187,8 +145,6 @@ void sort_extable(struct exception_table_entry *start,
 		i += 4;
 		p->fixup -= i;
 		i += 4;
-		p->handler -= i;
-		i += 4;
 	}
 }