[PATCH 2.6.19] m32r: Fix access error handler to pass full 32-bitaddress

From: Hirokazu Takata
Date: Wed Dec 06 2006 - 05:01:08 EST


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

In the current m32r kernel implementation, we use an access error handler
to detect page faults.
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@xxxxxxxxxxxxxx>
---
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@xxxxxxxxxxxxxx>
Linux/M32R Project: http://www.linux-m32r.org/
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