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 C43A8C77B7A for ; Fri, 2 Jun 2023 08:36:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234451AbjFBIgQ (ORCPT ); Fri, 2 Jun 2023 04:36:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44054 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233979AbjFBIgN (ORCPT ); Fri, 2 Jun 2023 04:36:13 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 36F1418C for ; Fri, 2 Jun 2023 01:36:12 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 7C8D864D53 for ; Fri, 2 Jun 2023 08:36:11 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A0BA0C433D2; Fri, 2 Jun 2023 08:36:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1685694970; bh=xlo52tvORIIpAnKK0ye25x2JEs/59m3PnMQ4tQSI3ZI=; h=From:To:Cc:Subject:Date:From; b=vKm9x52pCunrUIYLGT58atc0EHT0W3vgjHDWxW1OE424s4XXxB8maeMRZHu2WzJB1 RXAh/H3CitZcjcmlB4ufE6zV1MfdfzBIRP6rsKk/MWCBCzRKkLPWjsRALC5OY9mN9k mW0oNk4PlmgXL+3OZ1gfmOLbl4s3cM0wIXAWU0W4T+BNkG50xDK8N1u4hL4w8KymK6 Nwee5wU/xAePlAXX1EhbQIxoy+MsJlL9+zRXW+yUUhs+bnt7OmNOZ3BBQ1pLhHutRe Sa6Jpi6VFuyO4ODb387NZ47hwAORy4H+gvwsokp1cmNHaOmAVzNBOXvBfJMwu6pkwN wtl6372lBcKSw== From: Chao Yu To: jaegeuk@kernel.org Cc: linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, Chao Yu Subject: [PATCH v2 2/2] f2fs: avoid dead loop in f2fs_issue_checkpoint() Date: Fri, 2 Jun 2023 16:36:05 +0800 Message-Id: <20230602083605.2470674-1-chao@kernel.org> X-Mailer: git-send-email 2.40.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org generic/082 reports a bug as below: __schedule+0x332/0xf60 schedule+0x6f/0xf0 schedule_timeout+0x23b/0x2a0 wait_for_completion+0x8f/0x140 f2fs_issue_checkpoint+0xfe/0x1b0 f2fs_sync_fs+0x9d/0xb0 sync_filesystem+0x87/0xb0 dquot_load_quota_sb+0x41b/0x460 dquot_load_quota_inode+0xa5/0x130 dquot_quota_on+0x4b/0x60 f2fs_quota_on+0xe3/0x1b0 do_quotactl+0x483/0x700 __x64_sys_quotactl+0x15c/0x310 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc The root casue is race case as below: Thread A Kworker IRQ - write() : write data to quota.user file - writepages - f2fs_submit_page_write - __is_cp_guaranteed return false - inc_page_count(F2FS_WB_DATA) - submit_bio - quotactl(Q_QUOTAON) - f2fs_quota_on - dquot_quota_on - dquot_load_quota_inode - vfs_setup_quota_inode : inode->i_flags |= S_NOQUOTA - f2fs_write_end_io - __is_cp_guaranteed return true - dec_page_count(F2FS_WB_CP_DATA) - dquot_load_quota_sb - f2fs_sync_fs - f2fs_issue_checkpoint - do_checkpoint - f2fs_wait_on_all_pages(F2FS_WB_CP_DATA) : loop due to F2FS_WB_CP_DATA count is negative Calling filemap_fdatawrite() and filemap_fdatawait() to keep all data clean before quota file setup. Signed-off-by: Chao Yu --- v2: - avoid compile warning reported by lkp@intel.com. fs/f2fs/super.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c index 2936bc870f5c..8fd23caa1ed9 100644 --- a/fs/f2fs/super.c +++ b/fs/f2fs/super.c @@ -2923,15 +2923,26 @@ static int f2fs_quota_on(struct super_block *sb, int type, int format_id, return -EBUSY; } + if (path->dentry->d_sb != sb) + return -EXDEV; + err = f2fs_quota_sync(sb, type); if (err) return err; - err = dquot_quota_on(sb, type, format_id, path); + inode = d_inode(path->dentry); + + err = filemap_fdatawrite(inode->i_mapping); if (err) return err; - inode = d_inode(path->dentry); + err = filemap_fdatawait(inode->i_mapping); + if (err) + return err; + + err = dquot_quota_on(sb, type, format_id, path); + if (err) + return err; inode_lock(inode); F2FS_I(inode)->i_flags |= F2FS_NOATIME_FL | F2FS_IMMUTABLE_FL; -- 2.40.1