From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-1783691-1518334823-2-17755508640185259449 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.001, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='US', FromHeader='com', MailFrom='org', XOriginatingCountry='UNK' X-Spam-charsets: plain='UTF-8' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1518334823; b=MaEPqebR0EQe74S/EsPkhROkiDdvW243m/DTLoJQ49LdvIK oc48fipgKSnFoiYnxZkUY2AaKaMwF20OjYx7vKn+BuSH8oJD4gaBnc677WYkZw+a Q5iAc1qZB0TcpoZcD6isYu8YE9DKX9Jn4eDr8XwbOxlTBPpXhxSMLneu0ezBKaq0 R4+GyjBim5DIrB1ycp+0CKD82GmhyaQQ1FL5ym5HwUX4LrWuoDQYbMFvouVFqUBh PYOp3Q0SJT0f83D/eujKQrC6FkUOYRtcszWD6CtjgU093JkJG1UG6qykTjqdio4f H0VemA8bo8Vcoc8Q6w3yEkhbFHwXSSnTB5bgdMg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=message-id:date:from:mime-version:to:cc :subject:references:in-reply-to:content-type :content-transfer-encoding:sender:list-id; s=arctest; t= 1518334823; bh=zFSiSUpdRm1hWkStXm7VZBd8/S7HS0Y5F0vabXL7yLY=; b=Q IaJDID2/LOK7ZOCLeMciZm6no3Ois/JbWkS3JuowVVAmGTzpwSAUWL1CET/5besx HzyTztP4i+o/okRxzw+jZe6J75u7oBymAP3o87wmc7hJbZEhbyYGHok7ChtfJ6iy gPlHQwtIUm/++vNZ8oT1w5uX0yXb1hYHbhCTit4R2wzKHQ1mJzAZLWf2ZI5qKU2d +QtlsmLD3MkmE3pwvYo/6MEw84TYLKlIxu0SSzf5390f808ngxBKMZfIT6jex8v4 f4i88XcIUSLTkqd/dFmMLKRo+hc1GZujjODD89u+0HTjCN0s8stQOCK43daJLLE1 G2e4+FifxwxDRlygoB1dg== ARC-Authentication-Results: i=1; mx3.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=huawei.com; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=huawei.com header.result=pass header_is_org_domain=yes Authentication-Results: mx3.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=huawei.com; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=huawei.com header.result=pass header_is_org_domain=yes Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752424AbeBKHkT (ORCPT ); Sun, 11 Feb 2018 02:40:19 -0500 Received: from szxga04-in.huawei.com ([45.249.212.190]:5192 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752224AbeBKHkS (ORCPT ); Sun, 11 Feb 2018 02:40:18 -0500 Message-ID: <5A7FF337.3000705@huawei.com> Date: Sun, 11 Feb 2018 15:39:35 +0800 From: alex chen User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:17.0) Gecko/20130509 Thunderbird/17.0.6 MIME-Version: 1.0 To: Ben Hutchings CC: , , , Joel Becker , Joseph Qi , Jun Piao , Mark Fasheh , Changwei Ge , Junxiao Bi , Linus Torvalds Subject: Re: [PATCH 3.2 39/79] ocfs2: should wait dio before inode lock in ocfs2_setattr() References: In-Reply-To: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.177.26.59] X-CFilter-Loop: Reflected Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: Hi Ben, ocfs2_dio_end_io_write() was introduced in 4.6 and the problem this patch fixes is only exist in the kernel 4.6 and above 4.6. Thanks, Alex On 2018/2/11 12:20, Ben Hutchings wrote: > 3.2.99-rc1 review patch. If anyone has any objections, please let me know. > > ------------------ > > From: alex chen > > commit 28f5a8a7c033cbf3e32277f4cc9c6afd74f05300 upstream. > > we should wait dio requests to finish before inode lock in > ocfs2_setattr(), otherwise the following deadlock will happen: > > process 1 process 2 process 3 > truncate file 'A' end_io of writing file 'A' receiving the bast messages > ocfs2_setattr > ocfs2_inode_lock_tracker > ocfs2_inode_lock_full > inode_dio_wait > __inode_dio_wait > -->waiting for all dio > requests finish > dlm_proxy_ast_handler > dlm_do_local_bast > ocfs2_blocking_ast > ocfs2_generic_handle_bast > set OCFS2_LOCK_BLOCKED flag > dio_end_io > dio_bio_end_aio > dio_complete > ocfs2_dio_end_io > ocfs2_dio_end_io_write > ocfs2_inode_lock > __ocfs2_cluster_lock > ocfs2_wait_for_mask > -->waiting for OCFS2_LOCK_BLOCKED > flag to be cleared, that is waiting > for 'process 1' unlocking the inode lock > inode_dio_end > -->here dec the i_dio_count, but will never > be called, so a deadlock happened. > > Link: http://lkml.kernel.org/r/59F81636.70508@huawei.com > Signed-off-by: Alex Chen > Reviewed-by: Jun Piao > Reviewed-by: Joseph Qi > Acked-by: Changwei Ge > Cc: Mark Fasheh > Cc: Joel Becker > Cc: Junxiao Bi > Signed-off-by: Andrew Morton > Signed-off-by: Linus Torvalds > Signed-off-by: Ben Hutchings > --- > fs/ocfs2/file.c | 9 +++++++-- > 1 file changed, 7 insertions(+), 2 deletions(-) > > --- a/fs/ocfs2/file.c > +++ b/fs/ocfs2/file.c > @@ -1130,6 +1130,13 @@ int ocfs2_setattr(struct dentry *dentry, > dquot_initialize(inode); > size_change = S_ISREG(inode->i_mode) && attr->ia_valid & ATTR_SIZE; > if (size_change) { > + /* > + * Here we should wait dio to finish before inode lock > + * to avoid a deadlock between ocfs2_setattr() and > + * ocfs2_dio_end_io_write() > + */ > + inode_dio_wait(inode); > + > status = ocfs2_rw_lock(inode, 1); > if (status < 0) { > mlog_errno(status); > @@ -1149,8 +1156,6 @@ int ocfs2_setattr(struct dentry *dentry, > if (status) > goto bail_unlock; > > - inode_dio_wait(inode); > - > if (i_size_read(inode) >= attr->ia_size) { > if (ocfs2_should_order_data(inode)) { > status = ocfs2_begin_ordered_truncate(inode, > > > . >