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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham 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 2AE85C433E0 for ; Fri, 29 May 2020 06:37:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F29FD20721 for ; Fri, 29 May 2020 06:37:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725834AbgE2GhJ (ORCPT ); Fri, 29 May 2020 02:37:09 -0400 Received: from szxga07-in.huawei.com ([45.249.212.35]:44710 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725308AbgE2GhI (ORCPT ); Fri, 29 May 2020 02:37:08 -0400 Received: from DGGEMS401-HUB.china.huawei.com (unknown [172.30.72.58]) by Forcepoint Email with ESMTP id E832D5B84A409C22E219; Fri, 29 May 2020 14:37:05 +0800 (CST) Received: from [10.134.22.195] (10.134.22.195) by smtp.huawei.com (10.3.19.201) with Microsoft SMTP Server (TLS) id 14.3.487.0; Fri, 29 May 2020 14:37:04 +0800 Subject: Re: [PATCH 3/3] f2fs: fix to cover meta flush with cp_lock To: Jaegeuk Kim CC: , , References: <20200527102753.15743-1-yuchao0@huawei.com> <20200527102753.15743-3-yuchao0@huawei.com> <20200527210233.GC206249@google.com> <23245f6e-528d-43ab-57b6-4ca16db43fe5@huawei.com> <20200528012615.GA232094@google.com> <8e30b18d-bf8e-dd2f-35fa-08bbfd1b507e@huawei.com> <20200528190010.GA162605@google.com> From: Chao Yu Message-ID: <9fa465a0-70b5-7d17-baf4-21224196e2bc@huawei.com> Date: Fri, 29 May 2020 14:37:02 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20200528190010.GA162605@google.com> Content-Type: text/plain; charset="windows-1252" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.134.22.195] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2020/5/29 3:00, Jaegeuk Kim wrote: > On 05/28, Chao Yu wrote: >> On 2020/5/28 9:26, Jaegeuk Kim wrote: >>> On 05/28, Chao Yu wrote: >>>> On 2020/5/28 5:02, Jaegeuk Kim wrote: >>>>> On 05/27, Chao Yu wrote: >>>>>> meta inode page should be flushed under cp_lock, fix it. >>>>> >>>>> It doesn't matter for this case, yes? >>>> >>>> It's not related to discard issue. >>> >>> I meant we really need this or not. :P >> >> Yes, let's keep that rule: flush meta pages under cp_lock, otherwise >> checkpoint flush order may be broken due to race, right? as checkpoint >> should write 2rd cp park page after flushing all meta pages. > > Well, this is for shutdown test, and thus we don't need to sync up here. I'm a little worried about race condition: f2fs_write_checkpoint do_checkpoint ... shutdown f2fs_sync_meta_pages stop_checkpoint ... Though, I haven't figure out potential damage of their racing. > >> >>> >>>> >>>> Now, I got some progress, I can reproduce that bug occasionally. >>>> >>>> Thanks, >>>> >>>>> >>>>>> >>>>>> Signed-off-by: Chao Yu >>>>>> --- >>>>>> fs/f2fs/file.c | 2 ++ >>>>>> 1 file changed, 2 insertions(+) >>>>>> >>>>>> diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c >>>>>> index f7de2a1da528..0fcae4d90074 100644 >>>>>> --- a/fs/f2fs/file.c >>>>>> +++ b/fs/f2fs/file.c >>>>>> @@ -2260,7 +2260,9 @@ static int f2fs_ioc_shutdown(struct file *filp, unsigned long arg) >>>>>> set_sbi_flag(sbi, SBI_IS_SHUTDOWN); >>>>>> break; >>>>>> case F2FS_GOING_DOWN_METAFLUSH: >>>>>> + mutex_lock(&sbi->cp_mutex); >>>>>> f2fs_sync_meta_pages(sbi, META, LONG_MAX, FS_META_IO); >>>>>> + mutex_unlock(&sbi->cp_mutex); >>>>>> f2fs_stop_checkpoint(sbi, false); >>>>>> set_sbi_flag(sbi, SBI_IS_SHUTDOWN); >>>>>> break; >>>>>> -- >>>>>> 2.18.0.rc1 >>>>> . >>>>> >>> . >>> > . >