[PATCH] x86_64 extable fixes

Make x86-64 compile again after recent extable changes.

arch/x86_64/kernel/setup.c

@@ -384,8 +384,6 @@ void __init setup_arch(char **cmdline_p)
 	conswitchp = &dummy_con;
 #endif
 #endif
-
-	exception_table_check(); 
 }
 
 #ifndef CONFIG_X86_TSC

arch/x86_64/kernel/traps.c

@@ -397,7 +397,8 @@ static void do_trap(int trapnr, int signr, char *str,
 
 	/* kernel trap */ 
 	{	     
-		unsigned long fixup = search_exception_table(regs->rip);
+		const struct exception_table_entry *fixup;
+		fixup = search_exception_tables(regs->rip);
 		if (fixup) {
 			extern int exception_trace; 
 			if (exception_trace)
@@ -405,7 +406,7 @@ static void do_trap(int trapnr, int signr, char *str,
 	             "%s: fixed kernel exception at %lx err:%ld\n",
 	             current->comm, regs->rip, error_code);
 		
-			regs->rip = fixup;
+			regs->rip = fixup->fixup;
 		} else	
 			die(str, regs, error_code);
 		return;
@@ -449,8 +450,6 @@ asmlinkage void do_int3(struct pt_regs * regs, long error_code)
 	do_trap(3, SIGTRAP, "int3", regs, error_code, NULL);
 }
 
-extern void dump_pagetable(unsigned long);
-
 asmlinkage void do_general_protection(struct pt_regs * regs, long error_code)
 {
 #ifdef CONFIG_CHECKING
@@ -479,13 +478,12 @@ asmlinkage void do_general_protection(struct pt_regs * regs, long error_code)
 
 	/* kernel gp */
 	{
-		unsigned long fixup;
-		fixup = search_exception_table(regs->rip);
+		const struct exception_table_entry *fixup;
+		fixup = search_exception_tables(regs->rip);
 		if (fixup) {
-			regs->rip = fixup;
+			regs->rip = fixup->fixup;
 			return;
 		}
-//		dump_pagetable(regs->rip); 
 		die("general protection fault", regs, error_code);
 	}
 }

arch/x86_64/mm/extable.c

@@ -6,32 +6,12 @@
 #include <linux/module.h>
 #include <linux/spinlock.h>
 #include <asm/uaccess.h>
-#include <linux/init.h>
 
-extern const struct exception_table_entry __start___ex_table[];
-extern const struct exception_table_entry __stop___ex_table[];
-
-
-void __init exception_table_check(void)
-{ 
-	const struct exception_table_entry *e;
-	unsigned long prev;
-
-	prev = 0;
-	for (e = __start___ex_table; e < __stop___ex_table; e++) { 		
-		if (e->insn < prev) {
-			panic("unordered exception table at %016lx:%016lx and %016lx:%016lx\n",
-				   prev, e[-1].fixup, 
-			       e->insn, e->fixup);
-		}		   	
-		prev = e->insn;
-	} 
-} 
-
-static unsigned long
-search_one_table(const struct exception_table_entry *first,
-		 const struct exception_table_entry *last,
-		 unsigned long value)
+/* Simple binary search */
+const struct exception_table_entry *
+search_extable(const struct exception_table_entry *first,
+	       const struct exception_table_entry *last,
+	       unsigned long value)
 {
         while (first <= last) {
 		const struct exception_table_entry *mid;
@@ -40,42 +20,11 @@ search_one_table(const struct exception_table_entry *first,
 		mid = (last - first) / 2 + first;
 		diff = mid->insn - value;
                 if (diff == 0)
-                        return mid->fixup;
+                        return mid;
                 else if (diff < 0)
                         first = mid+1;
                 else
                         last = mid-1;
         }
-        return 0;
-}
-
-extern spinlock_t modlist_lock;
-
-unsigned long
-search_exception_table(unsigned long addr)
-{
-	unsigned long ret = 0;
-	unsigned long flags;
-
-#ifndef CONFIG_MODULES
-	/* There is only the kernel to search.  */
-	return search_one_table(__start___ex_table, __stop___ex_table-1, addr);
-#else
-	/* The kernel is the last "module" -- no need to treat it special.  */
-	struct list_head *i;
-
-	spin_lock_irqsave(&modlist_lock, flags);
-	list_for_each(i, &extables) { 
-		struct exception_table *ex = 
-			list_entry(i,struct exception_table, list); 
-		if (ex->num_entries == 0) 
-			continue;
-		ret = search_one_table(ex->entry,
-				       ex->entry + ex->num_entries - 1, addr);
-		if (ret)
-			break;
-	}
-	spin_unlock_irqrestore(&modlist_lock, flags);
-	return ret;
-#endif
+        return NULL;
 }

arch/x86_64/mm/fault.c

@@ -22,6 +22,7 @@
 #include <linux/tty.h>
 #include <linux/vt_kern.h>		/* For unblank_screen() */
 #include <linux/compiler.h>
+#include <linux/module.h>
 
 #include <asm/system.h>
 #include <asm/uaccess.h>
@@ -101,7 +102,7 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long error_code)
 	struct mm_struct *mm;
 	struct vm_area_struct * vma;
 	unsigned long address;
-	unsigned long fixup;
+	const struct exception_table_entry *fixup;
 	int write;
 	siginfo_t info;
 
@@ -239,8 +240,9 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long error_code)
 no_context:
 	
 	/* Are we prepared to handle this kernel fault?  */
-	if ((fixup = search_exception_table(regs->rip)) != 0) {
-		regs->rip = fixup;
+	fixup = search_exception_tables(regs->rip);
+	if (fixup) {
+		regs->rip = fixup->fixup;
 		if (0 && exception_trace) 
 		printk(KERN_ERR 
 		       "%s: fixed kernel exception at %lx address %lx err:%ld\n", 

include/asm-x86_64/uaccess.h

@@ -71,9 +71,6 @@ struct exception_table_entry
 	unsigned long insn, fixup;
 };
 
-/* Returns 0 if exception not found and fixup otherwise.  */
-extern unsigned long search_exception_table(unsigned long);
-
 
 /*
  * These are the main single-value transfer routines.  They automatically