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 X-Spam-Level: X-Spam-Status: No, score=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 50FC3C3A59E for ; Mon, 2 Sep 2019 15:43:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2F6CB21744 for ; Mon, 2 Sep 2019 15:43:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726063AbfIBPnC (ORCPT ); Mon, 2 Sep 2019 11:43:02 -0400 Received: from szxga08-in.huawei.com ([45.249.212.255]:51844 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725807AbfIBPnC (ORCPT ); Mon, 2 Sep 2019 11:43:02 -0400 Received: from DGGEMM402-HUB.china.huawei.com (unknown [172.30.72.53]) by Forcepoint Email with ESMTP id 539BF47A9E3273CCD727; Mon, 2 Sep 2019 23:22:33 +0800 (CST) Received: from dggeme762-chm.china.huawei.com (10.3.19.108) by DGGEMM402-HUB.china.huawei.com (10.3.20.210) with Microsoft SMTP Server (TLS) id 14.3.439.0; Mon, 2 Sep 2019 23:22:33 +0800 Received: from architecture4 (10.140.130.215) by dggeme762-chm.china.huawei.com (10.3.19.108) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1591.10; Mon, 2 Sep 2019 23:22:30 +0800 Date: Mon, 2 Sep 2019 23:21:39 +0800 From: Gao Xiang To: Christoph Hellwig CC: , Chao Yu , , , Alexander Viro , LKML , "Greg Kroah-Hartman" , Andrew Morton , Stephen Rothwell , Theodore Ts'o , Pavel Machek , Amir Goldstein , "Darrick J . Wong" , "Dave Chinner" , Jaegeuk Kim , Jan Kara , Richard Weinberger , Linus Torvalds , , Chao Yu , Miao Xie , Li Guifu , Fang Wei Subject: Re: [PATCH v8 11/24] erofs: introduce xattr & posixacl support Message-ID: <20190902152139.GB179615@architecture4> References: <20190815044155.88483-1-gaoxiang25@huawei.com> <20190815044155.88483-12-gaoxiang25@huawei.com> <20190902125711.GA23462@infradead.org> <20190902130644.GT2752@suse.cz> <813e1b65-e6ba-631c-6506-f356738c477f@kernel.org> <20190902142037.GW2752@twin.jikos.cz> <20190902150640.GA23089@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20190902150640.GA23089@infradead.org> User-Agent: Mutt/1.9.4 (2018-02-28) X-Originating-IP: [10.140.130.215] X-ClientProxiedBy: dggeme710-chm.china.huawei.com (10.1.199.106) To dggeme762-chm.china.huawei.com (10.3.19.108) X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Christoph, On Mon, Sep 02, 2019 at 08:06:40AM -0700, Christoph Hellwig wrote: > On Mon, Sep 02, 2019 at 04:20:37PM +0200, David Sterba wrote: > > Oh right, I think the reasons are historical and that we can remove the > > options nowadays. From the compatibility POV this should be safe, with > > ACLs compiled out, no tool would use them, and no harm done when the > > code is present but not used. > > > > There were some efforts by embedded guys to make parts of kernel more > > configurable to allow removing subsystems to reduce the final image > > size. In this case I don't think it would make any noticeable > > difference, eg. the size of fs/btrfs/acl.o on release config is 1.6KiB, > > while the whole module is over 1.3MiB. > > Given that the erofs folks have an actual use case for it I think > it is fine to keep the options, I just wanted to ensure this wasn't > copy and pasted for no good reason. Note that for XFS we don't have > an option for xattrs, as those are integral to a lot of file system > features. WE have an ACL option mostly for historic reasons. Add a word, xattr is necessary for Android, but ACL is not. I'm fine with killing these two, but EROFS can be used in more wider embedded scenerios (other than Android), I have no idea xattrs is useful for those embedded devices... Thanks, Gao Xiang