From 336f1d326831873ffab6de5fcec4b3be05103ae0 Mon Sep 17 00:00:00 2001 From: Paul Mundt Date: Mon, 19 May 2008 19:39:33 +0900 Subject: [PATCH] sh: Fix up restorer in debug_trap exception return path. There are a few different types of debug trap exceptions, though now that they are all going through a special jump table, the restorer needs to be unified as well. Presently this is falling through the ret_from_fork path, which more or less does the right thing on SH-3/4 whilst being completely unsuitable on MMU-less targets. Ultimately what we want here is a branch through the platform's restore_all directly, without worrying about the retval being clobbered. We can accomplish that through a branch to __restore_all directly, so switch it so we come back from the jump table and branch to the restorer. This fixes up a recursion in the nommu WARN_ON() path, as well as some other userspace nastiness where said recursion caused serious stack corruption. Signed-off-by: Paul Mundt --- arch/sh/kernel/entry-common.S | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/arch/sh/kernel/entry-common.S b/arch/sh/kernel/entry-common.S index 9a1837d5b54e..718bd2356b34 100644 --- a/arch/sh/kernel/entry-common.S +++ b/arch/sh/kernel/entry-common.S @@ -1,9 +1,6 @@ -/* $Id: entry.S,v 1.37 2004/06/11 13:02:46 doyu Exp $ - * - * linux/arch/sh/entry.S - * +/* * Copyright (C) 1999, 2000, 2002 Niibe Yutaka - * Copyright (C) 2003 Paul Mundt + * Copyright (C) 2003 - 2008 Paul Mundt * * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive @@ -282,7 +279,9 @@ debug_trap: mov.l 1f, r8 add r0, r8 mov.l @r8, r8 - jmp @r8 + jsr @r8 + nop + bra __restore_all nop .align 2 -- 2.20.1