Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760655AbZLJHcX (ORCPT ); Thu, 10 Dec 2009 02:32:23 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1760519AbZLJHcU (ORCPT ); Thu, 10 Dec 2009 02:32:20 -0500 Received: from mail-fx0-f213.google.com ([209.85.220.213]:58727 "EHLO mail-fx0-f213.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760646AbZLJHcT (ORCPT ); Thu, 10 Dec 2009 02:32:19 -0500 Message-ID: <4B20A3E7.70806@monstr.eu> Date: Thu, 10 Dec 2009 08:31:51 +0100 From: Michal Simek Reply-To: monstr@monstr.eu User-Agent: Thunderbird 2.0.0.22 (X11/20090625) MIME-Version: 1.0 To: steve@digidescorp.com CC: microblaze-uclinux@itee.uq.edu.au, linux-kernel@vger.kernel.org Subject: Re: [PATCH] microblaze: nommu: Don't clobber R11 on syscalls References: <1260400422-2805-1-git-send-email-steve@digidescorp.com> In-Reply-To: <1260400422-2805-1-git-send-email-steve@digidescorp.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1519 Lines: 42 Hi Steve, steve@digidescorp.com wrote: > The noMMU syscall trap has a bug that causes R11 to be zero on return to > userland. Remove the extra "save" of R11 responsible for the bug. Can you please look if is even possible to remove that one line below? ( I mean line 212 - lwi r11, r0, PER_CPU(KM) */ Interrupt rutine don't have it too. I am pretty sure that we can remove that line too. Thanks for testing, Michal > > Signed-off-by: Steven J. Magnani > --- > diff -uprN a/arch/microblaze/kernel/entry-nommu.S b/arch/microblaze/kernel/entry-nommu.S > --- a/arch/microblaze/kernel/entry-nommu.S 2009-12-09 17:05:11.000000000 -0600 > +++ b/arch/microblaze/kernel/entry-nommu.S 2009-12-09 17:07:31.000000000 -0600 > @@ -208,7 +208,6 @@ ENTRY(_user_exception) > lwi r1, r1, TS_THREAD_INFO /* get the thread info */ > /* calculate kernel stack pointer */ > addik r1, r1, THREAD_SIZE - PT_SIZE > - swi r11, r0, PER_CPU(R11_SAVE) /* temporarily save r11 */ > lwi r11, r0, PER_CPU(KM) /* load mode indicator */ > 2: > swi r11, r1, PT_MODE /* store the mode */ > -- Michal Simek, Ing. (M.Eng) w: www.monstr.eu p: +42-0-721842854 Maintainer of Linux kernel 2.6 Microblaze Linux - http://www.monstr.eu/fdt/ Microblaze U-BOOT custodian -- 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/