Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758740Ab0DVUnr (ORCPT ); Thu, 22 Apr 2010 16:43:47 -0400 Received: from kroah.org ([198.145.64.141]:37275 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756073Ab0DVT1s (ORCPT ); Thu, 22 Apr 2010 15:27:48 -0400 X-Mailbox-Line: From gregkh@kvm.kroah.org Thu Apr 22 12:09:09 2010 Message-Id: <20100422190909.894750689@kvm.kroah.org> User-Agent: quilt/0.48-4.4 Date: Thu, 22 Apr 2010 12:07:59 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Matt Fleming , Paul Mundt Subject: [028/197] sh: Enable the mmu in start_secondary() In-Reply-To: <20100422191857.GA13268@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1360 Lines: 39 2.6.32-stable review patch. If anyone has any objections, please let us know. ------------------ From: Matt Fleming commit 4bea3418c737891894b9d3d3e9f8bbd67d66fa38 upstream. For the boot, enable_mmu() is called from setup_arch() but we don't call setup_arch() for any of the other cpus. So turn on the non-boot cpu's mmu inside of start_secondary(). I noticed this bug on an SMP board when trying to map I/O memory (smsc911x registers) into the kernel address space. Since the Address Translation bit in MMUCR wasn't set, accessing the virtual address where the smsc911x registers were supposedly mapped actually performed a physical address access. Signed-off-by: Matt Fleming Signed-off-by: Paul Mundt Signed-off-by: Greg Kroah-Hartman --- a/arch/sh/kernel/smp.c +++ b/arch/sh/kernel/smp.c @@ -69,6 +69,7 @@ asmlinkage void __cpuinit start_secondary(void) unsigned int cpu; struct mm_struct *mm = &init_mm; + enable_mmu(); atomic_inc(&mm->mm_count); atomic_inc(&mm->mm_users); current->active_mm = mm; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/