Return-Path: Received: from natasha.panasas.com ([67.152.220.90]:55427 "EHLO natasha.panasas.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751704Ab1HLVPa (ORCPT ); Fri, 12 Aug 2011 17:15:30 -0400 Message-ID: <4E4597E7.7090504@panasas.com> Date: Fri, 12 Aug 2011 14:15:19 -0700 From: Boaz Harrosh To: Jim Rees CC: Benny Halevy , Subject: Re: two callback patches References: <20110812204809.GA4760@merit.edu> In-Reply-To: <20110812204809.GA4760@merit.edu> Content-Type: text/plain; charset="UTF-8" Sender: linux-nfs-owner@vger.kernel.org List-ID: MIME-Version: 1.0 On 08/12/2011 01:48 PM, Jim Rees wrote: > When you get a chance, could you pull these into pnfs-all-latest? You'll > find them on the head of my for-benny branch, and I assume upstream. > Right and some other bug fixes as well. I find that all of trond/linux-next branch are needed for proper run with v3.1-rc1 stuff. Best is if you can merge in trond/linux-next at the client branch side if the pnfs tree. Thanks Boaz > commit 3070296f2b3ddc094bda51286c3e9687d59d2a22 > Author: Trond Myklebust > Date: Tue Aug 2 14:50:40 2011 -0400 > > NFSv4.1: Return NFS4ERR_BADSESSION to callbacks during session resets > > If the client is in the process of resetting the session when it receives > a callback, then returning NFS4ERR_DELAY may cause a deadlock with the > DESTROY_SESSION call. > > Basically, if the client returns NFS4ERR_DELAY in response to the > CB_SEQUENCE call, then the server is entitled to believe that the > client is busy because it is already processing that call. In that > case, the server is perfectly entitled to respond with a > NFS4ERR_BACK_CHAN_BUSY to any DESTROY_SESSION call. > > Fix this by having the client reply with a NFS4ERR_BADSESSION in > response to the callback if it is resetting the session. > > Cc: stable@kernel.org [2.6.38+] > Signed-off-by: Trond Myklebust > > commit a8446678ba8b850bcac2286c6ed803c339049096 > Author: Trond Myklebust > Date: Tue Aug 2 14:50:39 2011 -0400 > > NFSv4.1: Fix the callback 'highest_used_slotid' behaviour > > Currently, there is no guarantee that we will call nfs4_cb_take_slot() even > though nfs4_callback_compound() will consistently call > nfs4_cb_free_slot() provided the cb_process_state has set the 'clp' field. > The result is that we can trigger the BUG_ON() upon the next call to > nfs4_cb_take_slot(). > > This patch fixes the above problem by using the slot id that was taken in > the CB_SEQUENCE operation as a flag for whether or not we need to call > nfs4_cb_free_slot(). > It also fixes an atomicity problem: we need to set tbl->highest_used_slotid > atomically with the check for NFS4_SESSION_DRAINING, otherwise we end up > racing with the various tests in nfs4_begin_drain_session(). > > Cc: stable@kernel.org [2.6.38+] > Signed-off-by: Trond Myklebust > -- > To unsubscribe from this list: send the line "unsubscribe linux-nfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html