[PATCH 2.6.19] m32r: Fix ace_handler to pass full 32-bit address

[PATCH 2.6.19] m32r: Fix ace_handler to pass full 32-bit address

[Hirokazu Takata]

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>
---
 arch/m32r/kernel/entry.S |    2 --
 arch/m32r/mm/fault.c     |    4 ++--
 2 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/arch/m32r/kernel/entry.S b/arch/m32r/kernel/entry.S
index 5b01fd2..a2c472c 100644
--- a/arch/m32r/kernel/entry.S
+++ b/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:
diff --git a/arch/m32r/mm/fault.c b/arch/m32r/mm/fault.c
index 8d5f551..9b9feb0 100644
--- a/arch/m32r/mm/fault.c
+++ b/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;
 /*
-- 
1.4.4.1

--
Hirokazu Takata <takata@linux-m32r.org>
Linux/M32R Project:  http://www.linux-m32r.org/