From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:32940 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730931AbeKTDBI (ORCPT ); Mon, 19 Nov 2018 22:01:08 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Trond Myklebust Subject: [PATCH 4.19 156/205] NFSv4: Dont exit the state manager without clearing NFS4CLNT_MANAGER_RUNNING Date: Mon, 19 Nov 2018 17:27:43 +0100 Message-Id: <20181119162639.136105635@linuxfoundation.org> In-Reply-To: <20181119162616.586062722@linuxfoundation.org> References: <20181119162616.586062722@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: 4.19-stable 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 Cc: stable@vger.kernel.org # v4.15+ Signed-off-by: Greg Kroah-Hartman --- fs/nfs/nfs4state.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) --- a/fs/nfs/nfs4state.c +++ b/fs/nfs/nfs4state.c @@ -2583,11 +2583,12 @@ 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 (refcount_read(&clp->cl_count) > 1); - return; + goto out_drain; + out_error: if (strlen(section)) section_sep = ": "; @@ -2595,6 +2596,7 @@ 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); }