From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756547Ab3JNMrS (ORCPT ); Mon, 14 Oct 2013 08:47:18 -0400 Received: from mail-qc0-f176.google.com ([209.85.216.176]:60097 "EHLO mail-qc0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756153Ab3JNMrQ (ORCPT ); Mon, 14 Oct 2013 08:47:16 -0400 Date: Mon, 14 Oct 2013 08:47:12 -0400 From: Tejun Heo To: Yinghai Lu Cc: Greg KH , Kay Sievers , Linux Kernel Mailing List , "Eric W. Biederman" , Bjorn Helgaas Subject: Re: [PATCHSET v2] sysfs: use seq_file and unify regular and bin file handling Message-ID: <20131014124712.GA4722@htj.dyndns.org> References: <1380663729-18243-1-git-send-email-tj@kernel.org> <20131006004032.GA3601@kroah.com> <20131007170005.GB2481@htj.dyndns.org> <20131007231136.GB27270@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, guys. Sorry about the delay. On Fri, Oct 11, 2013 at 12:11:18PM -0700, Yinghai Lu wrote: > [ 448.189960] ------------[ cut here ]------------ > [ 448.195214] WARNING: CPU: 6 PID: 69219 at fs/sysfs/file.c:79 > sysfs_file_ops+0x59/0x70() So, that's "lockdep_assert_held(sd);" in sysfs_file_ops(). > [ 448.273805] [] sysfs_file_ops+0x59/0x70 > [ 448.279973] [] sysfs_open_file+0x88/0x330 Triggering from sysfs_open_file() > [ 448.366842] ------------[ cut here ]------------ > [ 448.372030] WARNING: CPU: 6 PID: 69219 at fs/sysfs/file.c:79 > sysfs_file_ops+0x59/0x70() ... > [ 448.457806] [] sysfs_seq_show+0xcb/0x180 and then from sysfs_seq_show(), which is weird because lockdep_assert_held(sd) checks whether sd's active ref is held and both do hold them. Hmm.... ah, right, I forgot about ->ignore_lockdep, we need to skip the assertion for files marked with ignore_lockdep. Will send a patch soon. Thanks. -- tejun