From: Trond Myklebust Subject: Re: Fw: Deadlock regression in v2.6.31.6 Date: Thu, 26 Nov 2009 10:20:59 -0500 Message-ID: <1259248859.6715.50.camel@localhost> References: <20091124233555.da6439c4.akpm@linux-foundation.org> <64b4daae0911250056g3364d24l98850a272dcfe483@mail.gmail.com> <1259159512.3314.12.camel@localhost> <64b4daae0911251511q7a070b0aj1c07cdc5d6719b41@mail.gmail.com> <1259247707.6715.46.camel@localhost> <64b4daae0911260707i4064f608w4f7169441640567@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Cc: Andrew Morton , linux-nfs@vger.kernel.org To: "Stephen R. van den Berg" Return-path: Received: from mail-out1.uio.no ([129.240.10.57]:56722 "EHLO mail-out1.uio.no" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755050AbZKZPU7 (ORCPT ); Thu, 26 Nov 2009 10:20:59 -0500 In-Reply-To: <64b4daae0911260707i4064f608w4f7169441640567-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org> Sender: linux-nfs-owner@vger.kernel.org List-ID: On Thu, 2009-11-26 at 16:07 +0100, Stephen R. van den Berg wrote: > On Thu, Nov 26, 2009 at 16:01, Trond Myklebust > wrote: > > On Thu, 2009-11-26 at 00:11 +0100, Stephen R. van den Berg wrote: > >> 1.2.3.167 is the Linux client kernel which locks up, 1.2.3.151 is the > >> unfs server. > >> It looks like the client terminates the TCP connection. The server > >> confirms it, the client then sends a final acknowledge. At that point > >> the client kernel locks up in the infinite loop. > > > OK. Have you tried running with RPCDBG_TRANS debugging enabled? I > > suspect you might see a flood of 'sendmsg returned unrecognized error' > > or 'connect returned unhandled error' messages if you do. > > The pcap trace is not conclusive (enough)? > I can run with RPCDBG_TRANS enabled, if it is needed to further > pinpoint the problem. The pcap trace shows what is happening: the socket is getting closed correctly, and so the RPC client needs to initiate a reconnection before it can transmit again. What I don't understand is why it is failing to do so... Trond