From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754808AbdARLJl (ORCPT ); Wed, 18 Jan 2017 06:09:41 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:41194 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754722AbdARLIg (ORCPT ); Wed, 18 Jan 2017 06:08:36 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Trond Myklebust Subject: [PATCH 4.9 089/120] pNFS: Fix race in pnfs_wait_on_layoutreturn Date: Wed, 18 Jan 2017 11:46:47 +0100 Message-Id: <20170118104651.756203617@linuxfoundation.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20170118104648.120216880@linuxfoundation.org> References: <20170118104648.120216880@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Trond Myklebust commit ee284e35d8c71bf5d4d807eaff6f67a17134b359 upstream. We must put the task to sleep while holding the inode->i_lock in order to ensure atomicity with the test for NFS_LAYOUT_RETURN. Fixes: 500d701f336b ("NFS41: make close wait for layoutreturn") Signed-off-by: Trond Myklebust Signed-off-by: Greg Kroah-Hartman --- fs/nfs/pnfs.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) --- a/fs/nfs/pnfs.c +++ b/fs/nfs/pnfs.c @@ -1257,13 +1257,11 @@ bool pnfs_wait_on_layoutreturn(struct in * i_lock */ spin_lock(&ino->i_lock); lo = nfsi->layout; - if (lo && test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) + if (lo && test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) { + rpc_sleep_on(&NFS_SERVER(ino)->roc_rpcwaitq, task, NULL); sleep = true; + } spin_unlock(&ino->i_lock); - - if (sleep) - rpc_sleep_on(&NFS_SERVER(ino)->roc_rpcwaitq, task, NULL); - return sleep; }