[PATCH] m32r: fix ace_handler to pass full 32-bit address

Don't mask the lower 12-bit of the page fault address.

In the current m32r kernel implementation, we use an access exception
to detect page faults.

This patch fixes ace_handler (access exception handler) for m32r.  In order to
check userspace address in do_page_fault, we have to pass full 32-bit address
to do_page_fault.

Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/m32r/kernel/entry.S

@@ -596,8 +596,6 @@ ENTRY(ace_handler)
 	beqz	r1, inst
 oprand:
 	ld	r2, @(low(MDEVA_offset),r2)	; set address
-	srli	r2, #12
-	slli	r2, #12
 	srli	r1, #1
 	bra	1f
 inst:

arch/m32r/mm/fault.c

@@ -173,7 +173,7 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long error_code,
 		goto good_area;
 	if (!(vma->vm_flags & VM_GROWSDOWN))
 		goto bad_area;
-#if 0
+
 	if (error_code & ACE_USERMODE) {
 		/*
 		 * accessing the stack below "spu" is always a bug.
@@ -184,7 +184,7 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long error_code,
 		if (address + 4 < regs->spu)
 			goto bad_area;
 	}
-#endif
+
 	if (expand_stack(vma, address))
 		goto bad_area;
 /*