From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936698AbXGUA3K (ORCPT ); Fri, 20 Jul 2007 20:29:10 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755705AbXGUA24 (ORCPT ); Fri, 20 Jul 2007 20:28:56 -0400 Received: from wa-out-1112.google.com ([209.85.146.177]:55213 "EHLO wa-out-1112.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752505AbXGUA2z (ORCPT ); Fri, 20 Jul 2007 20:28:55 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=Syxr7Eqza2qTMlUvVjBBXjwnTiJ1tBOyLHOwYfixoTsI4AtQUatNDJOg6EJC03wfH7zHMUiHrALpokKjIn+IsRAx8UyBEgwH7/wNX7QceuA9IDhp56PCB//5afH5RcuSaqbawCnW3zPCjKfTBJSKUZBCvcx8PrkJrQ89SwPmNlg= Message-ID: <6bffcb0e0707201728u6deeccd1j453ff89d0767dccc@mail.gmail.com> Date: Sat, 21 Jul 2007 02:28:52 +0200 From: "Michal Piotrowski" To: "Satyam Sharma" Subject: Re: [broken-out-2007-07-20-00-22] kernel bug at kernel/params:570 Cc: "Greg KH" , "Andrew Morton" , rdunlap@xenotime.net, LKML In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <6bffcb0e0707200932p2b905e21g7970172ca7eb4da7@mail.gmail.com> <20070720225047.GA17520@suse.de> <20070720155912.079c5a27.akpm@linux-foundation.org> <20070720231052.GA19752@suse.de> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On 21/07/07, Satyam Sharma wrote: > Oh, which means ... > > > On 7/21/07, Satyam Sharma wrote: > > On 7/21/07, Greg KH wrote: > > > On Fri, Jul 20, 2007 at 03:59:12PM -0700, Andrew Morton wrote: > > > > On Fri, 20 Jul 2007 15:50:47 -0700 > > > > Greg KH wrote: > > > > > > > > > On Fri, Jul 20, 2007 at 06:32:21PM +0200, Michal Piotrowski wrote: > > > > > > Hi Greg, > > > > > > > > > > > > This looks like a sysfs bug > > > > > > http://www.stardust.webpages.pl/files/tbf/bitis-gabonica/ > > > > > > broken-out-2007-07-20-00-22/00003.jpg > > > > > > > > > > > > l *kernel_param_sysfs_setup+0x75 > > > > > > 0xc13c0894 is in kernel_param_sysfs_setup (kernel/params.c:570). > > > > > > 565 mk->mod = THIS_MODULE; > > > > > > 566 kobj_set_kset_s(mk, module_subsys); > > > > > > > 567 kobject_set_name(&mk->kobj, name); > > Shouldn't the return of kobject_set_name() be checked here? > > [ Looking at code, and realizing that kobject_set_name() manages to > succeed even when given a null string! ] > > > > > > > 568 kobject_init(&mk->kobj); > > > > > > 569 ret = kobject_add(&mk->kobj); > > > > > > 570 BUG_ON(ret < 0); > > > > > > 571 param_sysfs_setup(mk, kparam, num_params, name_skip); > > > > > > 572 kobject_uevent(&mk->kobj, KOBJ_ADD); > > > > > > 573 } > > > > > > 574 > > > > > > > > > > > > http://www.stardust.webpages.pl/files/tbf/bitis-gabonica/ > > > > > > broken-out-2007-07-20-00-22/mm-config > > > > > > > > > > What kernel version is this happening on? The -mm tree? Can you try > > > > > Linus's tree instead? > > > > > > > > > > It looks like there was some needed information right before the first > > > > > stack dump, showing exactly what kobject was trying to be added that was > > > > > already present. Odds are this is a kernel parameter with the same name > > > > > as a duplicate one within the same module, > > > > I don't think that's an -EEXIST. > > > > I think what we have here is kobject_add() exiting with -EINVAL. > > (kobject attempted to be registered with no name!) > > > > [ The first trace on that screen shows: kobject_shadow_add+0x5b/0x189. > > That's the WARN_ON(1) at lib/kobject.c:176. If it was a EEXIST case, > > we would've seen an offset in kobject_shadow_add closer to 0x189, > > because the dump_stack() for EEXIST is barely 4 instructions before > > we return from that function. ] > > > > > > > but the trick is going to be > > > > > trying to figure out what module is causing this. > > > > So I'd guess we want to search for a module that's passing a kobject * > > to kobject_add() such that !kobj->k_name is true. > > Oh, that's kernel_param_sysfs_setup itself. So we actually need to > search for a built-in module in Michal's config that ... has an ... empty > "" modname !? I'll try to figure out this > Shouldn't that turn up pretty quickly in a grep? > > How do I do that, btw? > Regards, Michal -- LOG http://www.stardust.webpages.pl/log/