From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754103Ab3APHko (ORCPT ); Wed, 16 Jan 2013 02:40:44 -0500 Received: from mail-da0-f53.google.com ([209.85.210.53]:60860 "EHLO mail-da0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752676Ab3APHkm (ORCPT ); Wed, 16 Jan 2013 02:40:42 -0500 Message-ID: <50F65972.9030605@gmail.com> Date: Wed, 16 Jan 2013 15:40:34 +0800 From: "yanyg02@gmail.com" User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:17.0) Gecko/20130107 Thunderbird/17.0.2 MIME-Version: 1.0 To: Greg KH CC: linux-kernel@vger.kernel.org Subject: Re: [PATCH] sysfs: sysfs_update_group always fails and generates a WARNING CALL-trace References: <20130116070425.GA3972@yvit> <20130116071509.GA865@kroah.com> In-Reply-To: <20130116071509.GA865@kroah.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Sorry. I'm a fresh. This is my first patch commit. And still now *mutt* does not configured properly. I will study howto and commit patch again. Sorry. ------------------- > On Wed, Jan 16, 2013 at 03:04:25PM +0800, yanyg wrote: >> @sysfs_update_group@ always fails and borns a WARNING CALL-trace >> if the group exists. BUT still now, no *reference* of this routine at all. > I don't understand. OK, sysfs routine @sysfs_update_group@ *never* works properly > >> >From fe40df7d716658a1fbdab79768628c81d4363428 Mon Sep 17 00:00:00 2001 >> From: yanyg >> Date: Wed, 16 Jan 2013 11:25:15 +0800 >> Subject: [PATCH] sysfs-fixes: >> >> @sysfs_update_group@ always fail and generates WARNING CALL trace. >> fix @internal_create_group@ to avoid it. > Why did you embed the patch here, with the words above it? I would have > to edit it to apply it :( > > It's also not in a format I can apply (no signed-off-by: line.) So sorry. > >> --- >> fs/sysfs/group.c | 14 ++++++++++---- >> 1 files changed, 10 insertions(+), 4 deletions(-) >> >> diff --git a/fs/sysfs/group.c b/fs/sysfs/group.c >> index 2df555c..51fcf62 100644 >> --- a/fs/sysfs/group.c >> +++ b/fs/sysfs/group.c >> @@ -60,7 +60,7 @@ static int internal_create_group(struct kobject *kobj, int update, >> const struct attribute_group *grp) >> { >> struct sysfs_dirent *sd; >> - int error; >> + int error, do_put = 0; >> >> BUG_ON(!kobj || (!update && !kobj->sd)); >> >> @@ -73,9 +73,14 @@ static int internal_create_group(struct kobject *kobj, int update, >> return -EINVAL; >> } >> if (grp->name) { >> - error = sysfs_create_subdir(kobj, grp->name, &sd); >> - if (error) >> - return error; >> + sd = sysfs_get_dirent(kobj->sd, NULL, grp->name); >> + if (sd) { >> + do_put = 1; >> + } else { >> + error = sysfs_create_subdir(kobj, grp->name, &sd); >> + if (error) >> + return error; >> + } >> } else >> sd = kobj->sd; >> sysfs_get(sd); >> @@ -85,6 +90,7 @@ static int internal_create_group(struct kobject *kobj, int update, >> sysfs_remove_subdir(sd); >> } >> sysfs_put(sd); >> + if (do_put) sysfs_put(sd); > Always run your patches through scripts/checkpatch.pl and fix the > problems it tells you about. > > What code in the kernel is hitting this today? I write a simply virtual block device driver which calls @sysfs_update_group@ to updates attributes and modes, it fails. YOU can reproduce the bug by append @sysfs_update_group@ at below any of @sysfs_create_group@ call. > > thanks, > > greg k-h > So too sorry for my silly. yanyg02