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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS 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 6A38DC169C4 for ; Sun, 3 Feb 2019 14:32:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 418562073D for ; Sun, 3 Feb 2019 14:32:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731244AbfBCOcG (ORCPT ); Sun, 3 Feb 2019 09:32:06 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:55222 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728932AbfBCOT6 (ORCPT ); Sun, 3 Feb 2019 09:19:58 -0500 Received: from cable-78.29.236.164.coditel.net ([78.29.236.164] helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1gqIcm-00063w-AC; Sun, 03 Feb 2019 14:19:56 +0000 Received: from ben by deadeye with local (Exim 4.92-RC4) (envelope-from ) id 1gqI9h-0007CC-2L; Sun, 03 Feb 2019 14:49:53 +0100 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, Denis Kirjanov , "Trond Myklebust" Date: Sun, 03 Feb 2019 14:45:08 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 196/305] NFSv4: Don't exit the state manager without clearing NFS4CLNT_MANAGER_RUNNING In-Reply-To: X-SA-Exim-Connect-IP: 78.29.236.164 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.63-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Trond Myklebust commit 21a446cf186570168b7281b154b1993968598aca upstream. If we exit the NFSv4 state manager due to a umount, then we can end up leaving the NFS4CLNT_MANAGER_RUNNING flag set. If another mount causes the nfs4_client to be rereferenced before it is destroyed, then we end up never being able to recover state. Fixes: 47c2199b6eb5 ("NFSv4.1: Ensure state manager thread dies on last ...") Signed-off-by: Trond Myklebust [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings --- fs/nfs/nfs4state.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) --- a/fs/nfs/nfs4state.c +++ b/fs/nfs/nfs4state.c @@ -2427,11 +2427,12 @@ static void nfs4_state_manager(struct nf nfs4_clear_state_manager_bit(clp); /* Did we race with an attempt to give us more work? */ if (clp->cl_state == 0) - break; + return; if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0) - break; + return; } while (atomic_read(&clp->cl_count) > 1); - return; + goto out_drain; + out_error: if (strlen(section)) section_sep = ": "; @@ -2439,6 +2440,7 @@ out_error: " with error %d\n", section_sep, section, clp->cl_hostname, -status); ssleep(1); +out_drain: nfs4_end_drain_session(clp); nfs4_clear_state_manager_bit(clp); }