From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 40F19C7619A for ; Wed, 12 Apr 2023 03:24:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229692AbjDLDYb (ORCPT ); Tue, 11 Apr 2023 23:24:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33490 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229452AbjDLDY3 (ORCPT ); Tue, 11 Apr 2023 23:24:29 -0400 Received: from out30-132.freemail.mail.aliyun.com (out30-132.freemail.mail.aliyun.com [115.124.30.132]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 42E8630C8 for ; Tue, 11 Apr 2023 20:24:28 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R171e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018045192;MF=hsiangkao@linux.alibaba.com;NM=1;PH=DS;RN=10;SR=0;TI=SMTPD_---0VfuYNYL_1681269862; Received: from 30.97.48.227(mailfrom:hsiangkao@linux.alibaba.com fp:SMTPD_---0VfuYNYL_1681269862) by smtp.aliyun-inc.com; Wed, 12 Apr 2023 11:24:24 +0800 Message-ID: <7ea88962-1cda-55d3-04f9-2e471b4e89ad@linux.alibaba.com> Date: Wed, 12 Apr 2023 11:24:22 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:102.0) Gecko/20100101 Thunderbird/102.9.1 Subject: Re: [PATCH] erofs: don't access kobject object members directly To: Yangtao Li , Gao Xiang , Chao Yu , Yue Hu , Jeffle Xu , Huang Jianan , Greg KH , Dongliang Mu Cc: linux-erofs@lists.ozlabs.org, linux-kernel@vger.kernel.org References: <20230412031110.8965-1-frank.li@vivo.com> From: Gao Xiang In-Reply-To: <20230412031110.8965-1-frank.li@vivo.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org (+ Greg, Huang Jianan, Dongliang Mu) On 2023/4/12 11:11, Yangtao Li wrote: > It is better not to directly access the internal members of the > kobject object, especially kobject_init_and_add() may failure. > BTW remove unnecessary kobject_del(), kobject_put() actually covers > kobject removal automatically, which is single stage removal. Please at least Cc the proper people --- and write the previous background to the commit message *again*. I'd like to know the preferred way to do this since the previous discussion is unfinished. Also if you grep `state_in_sysfs`, actually there are some similar in-tree usage, also device_is_registered() is implemented like this: static inline int device_is_registered(struct device *dev) { return dev->kobj.state_in_sysfs; } Again, I'm not against this patch (I even prefer this one), but you should Cc the proper people and finish the previous topic first. Thanks, Gao Xiang > > Signed-off-by: Yangtao Li > --- > fs/erofs/internal.h | 1 + > fs/erofs/sysfs.c | 4 ++-- > 2 files changed, 3 insertions(+), 2 deletions(-) > > diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h > index f675050af2bb..f364b1e9b35b 100644 > --- a/fs/erofs/internal.h > +++ b/fs/erofs/internal.h > @@ -177,6 +177,7 @@ struct erofs_sb_info { > /* sysfs support */ > struct kobject s_kobj; /* /sys/fs/erofs/ */ > struct completion s_kobj_unregister; > + bool sysfs_registered; > > /* fscache support */ > struct fscache_volume *volume; > diff --git a/fs/erofs/sysfs.c b/fs/erofs/sysfs.c > index 435e515c0792..c38018d3c442 100644 > --- a/fs/erofs/sysfs.c > +++ b/fs/erofs/sysfs.c > @@ -228,6 +228,7 @@ int erofs_register_sysfs(struct super_block *sb) > kfree(str); > if (err) > goto put_sb_kobj; > + sbi->sysfs_registered = true; > return 0; > > put_sb_kobj: > @@ -240,8 +241,7 @@ void erofs_unregister_sysfs(struct super_block *sb) > { > struct erofs_sb_info *sbi = EROFS_SB(sb); > > - if (sbi->s_kobj.state_in_sysfs) { > - kobject_del(&sbi->s_kobj); > + if (sbi->sysfs_registered) { > kobject_put(&sbi->s_kobj); > wait_for_completion(&sbi->s_kobj_unregister); > }