[PATCH] Merge i386 fix for page fault to x86-64

From: Andi Kleen <ak@muc.de>

Merge the i386 fix for the page fault from Linus to x86-64
(I'm not actually sure what it fixes, but if it's good for 32bit
it is likely good for 64bit too)

arch/x86_64/mm/fault.c

@@ -340,7 +340,8 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long error_code)
 		}
        
 		tsk->thread.cr2 = address;
-		tsk->thread.error_code = error_code;
+		/* Kernel addresses are always protection faults */
+		tsk->thread.error_code = error_code | (address >= TASK_SIZE);
 		tsk->thread.trap_no = 14;
 		info.si_signo = SIGSEGV;
 		info.si_errno = 0;