From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752376AbaDXHS3 (ORCPT ); Thu, 24 Apr 2014 03:18:29 -0400 Received: from mail-pa0-f48.google.com ([209.85.220.48]:37677 "EHLO mail-pa0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751777AbaDXHS0 (ORCPT ); Thu, 24 Apr 2014 03:18:26 -0400 MIME-Version: 1.0 In-Reply-To: <20140422143036.GD15745@arch.cereza> References: <1397824031-4892-1-git-send-email-lftan@altera.com> <1397824031-4892-6-git-send-email-lftan@altera.com> <20140422143036.GD15745@arch.cereza> Date: Thu, 24 Apr 2014 09:18:25 +0200 X-Google-Sender-Auth: 4p9oP3X-JlQK7H9zG2-UGXS2wBg Message-ID: Subject: Re: [PATCH 08/28] nios2: MMU Fault handling From: Geert Uytterhoeven To: Ezequiel Garcia Cc: Ley Foon Tan , Linux-Arch , "linux-kernel@vger.kernel.org" , "linux-doc@vger.kernel.org" , LeyFoon Tan , cltang@codesourcery.com, "linux-arm-kernel@lists.infradead.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 22, 2014 at 4:30 PM, Ezequiel Garcia wrote: > On Apr 18, Ley Foon Tan wrote: >> + >> +bad_area_nosemaphore: >> + /* User mode accesses just cause a SIGSEGV */ >> + if (user_mode(regs)) { > > I found that it's useful to add some printing here, just as ARM > does. I carry this patch on my kernel: > > + printk(KERN_INFO "%s: unhandled page fault (%d) at 0x%08lx, cause %ld\n", > + current->comm, SIGSEGV, address, cause); > + show_regs(regs); > > Do you think we could do something like it? Maybe with a compile time option? Can this easily be triggered from userspace? If yes, please use pr_info_ratelimited(). Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds