Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753055AbZDGJzA (ORCPT ); Tue, 7 Apr 2009 05:55:00 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751279AbZDGJyu (ORCPT ); Tue, 7 Apr 2009 05:54:50 -0400 Received: from mail-fx0-f158.google.com ([209.85.220.158]:33120 "EHLO mail-fx0-f158.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751232AbZDGJyu (ORCPT ); Tue, 7 Apr 2009 05:54:50 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; b=rthdVZuL8x7yV3LY2ldP/T17XqT2eVuJUYg7iP46wATBt6nH1n2bFMoQ7RswpQRX60 KFpFhx3BMNkWFUcl4m8Q9ahjCP1Ur8bbor1ABdTv9DaxyqMOEYSE9tSVn3BVszpvatq/ JMVAD1TUWhUORv8IkX27Zk+b3TOnMscv+WOlg= Date: Tue, 7 Apr 2009 11:54:44 +0200 From: Andrea Righi To: Geert Uytterhoeven Cc: Krzysztof Helt , Andrew Morton , "Rafael J. Wysocki" , Andrey Borzenkov , "Antonino A. Daplas" , Linux Frame Buffer Device Development , linux-pm@lists.linux-foundation.org, Linux Kernel Development , Dave Jones , Harvey Harrison , Johannes Weiner , Stefan Richter Subject: Re: commit 66c1ca breaks fbdev mode switching Message-ID: <20090407095443.GA9526@linux> References: <498817E2.3020008@gmail.com> <1233783983-28802-1-git-send-email-righi.andrea@gmail.com> <200903221748.42871.arvidjaar@gmail.com> <200903221857.20473.rjw@sisk.pl> <20090322145219.ad294615.akpm@linux-foundation.org> <20090406204718.ce4909b3.krzysztof.h1@poczta.fm> <20090406214528.GA17259@linux> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1529 Lines: 41 On Tue, Apr 07, 2009 at 11:17:00AM +0200, Geert Uytterhoeven wrote: > On Mon, 6 Apr 2009, Andrea Righi wrote: > > On Mon, Apr 06, 2009 at 08:47:18PM +0200, Krzysztof Helt wrote: > > > The commit 66c1ca breaks fbdev mode switching. The first mode > > > (selected with mode_option or during boot) is ok but every mode > > > switch with fbset locks up computer. If the commit is reverted > > > mode switching works correctly. > > > > > > I do not understand why. I would be grateful if someone else > > > can confirm the problem as well. > > > > > > The commit's details are: > > > > > > commit 66c1ca019078220dc1bf968f2bb18421100ef147 > > > Author: Andrea Righi > > > Date: Tue Mar 31 15:25:18 2009 -0700 > > > > > > fbmem: fix fb_info->lock and mm->mmap_sem circular locking dependency > > > > Any lockdep info or oops? it just locks up the system? > > # echo d > /proc/sysrq-trigger > > [ 187.654947] INFO: lockdep is turned off. > > Strange, I do have lockdep enabled: > > CONFIG_LOCKDEP_SUPPORT=y > CONFIG_LOCKDEP=y > CONFIG_DEBUG_LOCKDEP=y Probably because lockdep reported the first lock bug and disabled the checking for the next lock bugs, to avoid log flooding of follow-up bugs. Search the first lockdep occurrence in dmesg. -Andrea -- 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/