Return-Path: linux-nfs-owner@vger.kernel.org Received: from fieldses.org ([174.143.236.118]:53444 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754123AbaHUVeW (ORCPT ); Thu, 21 Aug 2014 17:34:22 -0400 Received: from bfields by fieldses.org with local (Exim 4.76) (envelope-from ) id 1XKZzy-0001Sc-0u for linux-nfs@vger.kernel.org; Thu, 21 Aug 2014 17:34:22 -0400 Date: Thu, 21 Aug 2014 17:34:21 -0400 To: linux-nfs@vger.kernel.org Subject: kernel not recovering from statd port change Message-ID: <20140821213421.GA5474@fieldses.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii From: "J. Bruce Fields" Sender: linux-nfs-owner@vger.kernel.org List-ID: While testing server restart somebody noticed that knfsd can't recover from statd restarting with a new port. >From only a very quick skim of the code it looked like creating the nsm client with RPC_CLNT_CREATE_AUTOBIND should cause us to call rpcbind again on connection failures, but that doesn't seem to be working. Any ideas? I'll keep looking.... --b. commit 2c9fb5570fe2 Author: J. Bruce Fields Date: Wed Aug 20 17:21:32 2014 -0400 lockd: allow rebinding to statd During normal operation statd isn't restarted, but it may be if, for example, the server is shut down and restarted to simulate a shutdown or perform some kind of failover. In that case the kernel may need to query rpcbind again to get statd's new port number. Symptoms were locking failures after a manual server restart (without rebooting the machine), and loopback network traces showing the new kernel nfsd attempting to contact statd at its old port number. This was probably introduced by cb7323fffa85, which first allowed reusing the statd rpc client, but it looks like a reference count may typically have prevented any symptoms until e498daa81295 "LOCKD: Clear ln->nsm_clnt only when ln->nsm_users is zero". Fixes: cb7323fffa85 "lockd: create and use per-net NSM RPC clients on MON/UNMON requests" Signed-off-by: J. Bruce Fields diff --git a/fs/lockd/mon.c b/fs/lockd/mon.c index 1812f026960c..3bce1d318435 100644 --- a/fs/lockd/mon.c +++ b/fs/lockd/mon.c @@ -80,7 +80,8 @@ static struct rpc_clnt *nsm_create(struct net *net) .program = &nsm_program, .version = NSM_VERSION, .authflavor = RPC_AUTH_NULL, - .flags = RPC_CLNT_CREATE_NOPING, + .flags = RPC_CLNT_CREATE_NOPING| + RPC_CLNT_CREATE_AUTOBIND, }; return rpc_create(&args);