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,UNPARSEABLE_RELAY,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 BDF0FC33C9E for ; Mon, 3 Feb 2020 05:15:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 99BAD20661 for ; Mon, 3 Feb 2020 05:15:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727262AbgBCFPg (ORCPT ); Mon, 3 Feb 2020 00:15:36 -0500 Received: from out30-45.freemail.mail.aliyun.com ([115.124.30.45]:39163 "EHLO out30-45.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725768AbgBCFPg (ORCPT ); Mon, 3 Feb 2020 00:15:36 -0500 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R761e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e07417;MF=joseph.qi@linux.alibaba.com;NM=1;PH=DS;RN=8;SR=0;TI=SMTPD_---0TozpQ89_1580706930; Received: from JosephdeMacBook-Pro.local(mailfrom:joseph.qi@linux.alibaba.com fp:SMTPD_---0TozpQ89_1580706930) by smtp.aliyun-inc.com(127.0.0.1); Mon, 03 Feb 2020 13:15:31 +0800 Subject: Re: [PATCH] ocfs2: fix the oops problem when write cloned file To: Gang He , "mark@fasheh.com" , "jlbec@evilplan.org" , "gechangwei@live.cn" , Shuning Zhang Cc: "linux-kernel@vger.kernel.org" , "ocfs2-devel@oss.oracle.com" , "akpm@linux-foundation.org" References: <20200121050153.13290-1-ghe@suse.com> From: Joseph Qi Message-ID: Date: Mon, 3 Feb 2020 13:15:30 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.11; rv:60.0) Gecko/20100101 Thunderbird/60.9.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 20/2/3 10:17, Gang He wrote: > Hello Joseph, Changwei, Sunny and all, > > Could you help to review this patch? > This patch will fix the oops problem caused by write ocfs2 clone files. > The root cause is inode buffer head is NULL when calling ocfs2_refcount_cow. > Secondly, we should use EX meta lock when calling ocfs2_refcount_cow. > Before commit e74540b28556, we may also use NULL buffer head in case of overwrite, so why there is no such issue before? Thanks, Joseph