From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from oss.sgi.com (localhost [127.0.0.1]) by oss.sgi.com (8.12.5/8.12.5) with ESMTP id g6J6dMRw015519 for ; Thu, 18 Jul 2002 23:39:22 -0700 Received: (from majordomo@localhost) by oss.sgi.com (8.12.5/8.12.3/Submit) id g6J6dMXd015518 for linux-mips-outgoing; Thu, 18 Jul 2002 23:39:22 -0700 X-Authentication-Warning: oss.sgi.com: majordomo set sender to owner-linux-mips@oss.sgi.com using -f Received: from mx2.mips.com (ftp.mips.com [206.31.31.227]) by oss.sgi.com (8.12.5/8.12.5) with SMTP id g6J6dCRw015508 for ; Thu, 18 Jul 2002 23:39:12 -0700 Received: from newman.mips.com (ns-dmz [206.31.31.225]) by mx2.mips.com (8.12.5/8.12.5) with ESMTP id g6J6dbXb010467; Thu, 18 Jul 2002 23:39:37 -0700 (PDT) Received: from copfs01.mips.com (copfs01 [192.168.205.101]) by newman.mips.com (8.9.3/8.9.0) with ESMTP id XAA25042; Thu, 18 Jul 2002 23:39:38 -0700 (PDT) Received: from mips.com (copsun17 [192.168.205.27]) by copfs01.mips.com (8.11.4/8.9.0) with ESMTP id g6J6ddb10587; Fri, 19 Jul 2002 08:39:39 +0200 (MEST) Message-ID: <3D37B42A.8561D3BC@mips.com> Date: Fri, 19 Jul 2002 08:39:38 +0200 From: Carsten Langgaard X-Mailer: Mozilla 4.77 [en] (X11; U; SunOS 5.8 sun4u) X-Accept-Language: en MIME-Version: 1.0 To: Jun Sun CC: "H. J. Lu" , linux-mips@oss.sgi.com Subject: Re: Malta bus error References: <3D375B4C.9000403@mvista.com> <20020718180759.A2091@lucon.org> <3D3765F1.6050606@mvista.com> Content-Type: text/plain; charset=iso-8859-15 Content-Transfer-Encoding: 7bit X-Spam-Status: No, hits=0.0 required=5.0 tests= version=2.20 X-Spam-Level: Sender: owner-linux-mips@oss.sgi.com Precedence: bulk Jun Sun wrote: > H. J. Lu wrote: > > On Thu, Jul 18, 2002 at 05:20:28PM -0700, Jun Sun wrote: > > > >>I got the following bus error on Malta. Does anybody know what causes the > >>fault? Is there anyway to disable the error? Or we should install a malta > >>bus_error_handler() to discard this kind of error? > >> > >>Apparently the error has something to do with the code layout as it only > >>happens when I start to modify an unrelated function( do_ri()). > >> > >>I am using the latest linux_2_4 branch from oss.sgi.com CVS tree. > >> > > > > > > I got zero problems with 2.4 kernel on oss as of Jul 11 08:18. > > > > Me neither, until I made the following change. I of course use my own config > file. > > Using Malta's own BE handler to ignore bus error seems to fix the problem, > although I am not sure if it is the right fix. > Ignoring bus errors is usually not healthy, it indicates a problem, that I would prefer we find, instead of ignoring it. > > Jun > > --- arch/mips/kernel/traps.c.orig Thu Jul 18 15:39:50 2002 > +++ arch/mips/kernel/traps.c Thu Jul 18 16:49:32 2002 > @@ -614,8 +614,7 @@ > */ > asmlinkage void do_ri(struct pt_regs *regs) > { > - if (!user_mode(regs)) > - BUG(); > + die_if_kernel("no ll/sc emulation for kernel code", regs); > > #ifndef CONFIG_CPU_HAS_LLSC > > Jun -- _ _ ____ ___ Carsten Langgaard Mailto:carstenl@mips.com |\ /|||___)(___ MIPS Denmark Direct: +45 4486 5527 | \/ ||| ____) Lautrupvang 4B Switch: +45 4486 5555 TECHNOLOGIES 2750 Ballerup Fax...: +45 4486 5556 Denmark http://www.mips.com