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=-7.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY 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 7CAFDC433DF for ; Mon, 24 Aug 2020 15:09:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5A857206B5 for ; Mon, 24 Aug 2020 15:09:09 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="rsRCzv+o" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725781AbgHXPJH (ORCPT ); Mon, 24 Aug 2020 11:09:07 -0400 Received: from userp2130.oracle.com ([156.151.31.86]:34966 "EHLO userp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727036AbgHXPIp (ORCPT ); Mon, 24 Aug 2020 11:08:45 -0400 Received: from pps.filterd (userp2130.oracle.com [127.0.0.1]) by userp2130.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 07OF8Sxp005862; Mon, 24 Aug 2020 15:08:36 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=date : from : to : cc : subject : message-id : references : mime-version : content-type : in-reply-to; s=corp-2020-01-29; bh=WIEAunfvpebQwdMMGaTdQskRvyWBPd2/e+fiMwWEOVw=; b=rsRCzv+oms5y90ywKDeD6C4B5FBfEPPBhwuh66s522bqxpAwgCW/Xebx58muTnxzi2E5 omtmGaIPUsJAA+OSdkiR+Jfvjo9/XRAlYjwhFZ3z7DWJvJqllxwjXwC9AHoGrTsvBc6F j/4dfE+nUsBRC0WgBOYM5ZrHjTHcC9FdlxnHgIKZfcj7PtfI97h4hQGLdG+Dt+9chkM0 n7tVGyV+fUiyA/NExI0VHq0hjkzkjplVYGu6WmhXMUdp/viKUpuLU23aACrspWQF0aCs RRZFu4mFCnYDlrQxHMcqfJT2FfH+k4D0HT4D+FJ33BGlPnOG/oNR8Y0EyJiHsToEibiv Hg== Received: from aserp3020.oracle.com (aserp3020.oracle.com [141.146.126.70]) by userp2130.oracle.com with ESMTP id 333cshw5sh-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Mon, 24 Aug 2020 15:08:36 +0000 Received: from pps.filterd (aserp3020.oracle.com [127.0.0.1]) by aserp3020.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 07OF0Ce9193965; Mon, 24 Aug 2020 15:08:35 GMT Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by aserp3020.oracle.com with ESMTP id 333ru51wkd-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 24 Aug 2020 15:08:35 +0000 Received: from abhmp0002.oracle.com (abhmp0002.oracle.com [141.146.116.8]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id 07OF8Xs1021101; Mon, 24 Aug 2020 15:08:33 GMT Received: from localhost (/67.169.218.210) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Mon, 24 Aug 2020 08:08:33 -0700 Date: Mon, 24 Aug 2020 08:08:32 -0700 From: "Darrick J. Wong" To: Gao Xiang Cc: linux-xfs@vger.kernel.org, Christoph Hellwig , Dave Chinner Subject: Re: [RFC PATCH] xfs: use log_incompat feature instead of speculate matching Message-ID: <20200824150832.GV6096@magnolia> References: <20200823172421.GA16579@xiangao.remote.csb> <20200824081900.27573-1-hsiangkao@aol.com> <20200824083402.GB16579@xiangao.remote.csb> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200824083402.GB16579@xiangao.remote.csb> X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9722 signatures=668679 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxlogscore=999 phishscore=0 bulkscore=0 suspectscore=1 spamscore=0 mlxscore=0 adultscore=0 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2008240121 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9722 signatures=668679 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxscore=0 bulkscore=0 clxscore=1015 spamscore=0 priorityscore=1501 impostorscore=0 adultscore=0 lowpriorityscore=0 suspectscore=1 mlxlogscore=999 phishscore=0 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2008240122 Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On Mon, Aug 24, 2020 at 04:34:02PM +0800, Gao Xiang wrote: > On Mon, Aug 24, 2020 at 04:19:00PM +0800, Gao Xiang wrote: > > From: Gao Xiang > > > > Use a log_incompat feature just to be safe. > > If the current mount is in RO state, it will defer > > to next RW remount. > > > > Signed-off-by: Gao Xiang > > --- > > > > After some careful thinking, I think it's probably not working for > > supported V4 XFS filesystem. So, I think we'd probably insist on the > > previous way (correct me if I'm wrong)... > > > > (since xfs_sb_to_disk() refuses to set up any feature bits for non V5 > > fses. That is another awkward setting here (doesn't write out/check > > feature bits for V4 even though using V4 sb reserved fields) and > > unless let V4 completely RO since this commit. ) > > > > Just send out as a RFC patch. Not fully tested after I thought as above. > > Unless we also use sb_features2 for V4 filesystem to entirely > refuse to mount such V4 filesystem... > Some more opinions on this? Frankly, V4 is pretty old, so I wouldn't bother. We only build new features for V5 format. --D > Thanks, > Gao Xiang >