[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>

diff --git a/arch/m32r/kernel/entry.S b/arch/m32r/kernel/entry.S
index 5b01fd2096fc713aa171b2dd1cabb41b112d9973..a2c472c0549f1bccab78502aed0a51bcceb384da 100644 (file)
--- 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 8d5f551b5754305e87474b617b8e437925b48f76..9b9feb0f161075c09fb9f012017449e240f40cfa 100644 (file)
--- 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;
 /*