Return-Path: linux-nfs-owner@vger.kernel.org Received: from mail-wg0-f52.google.com ([74.125.82.52]:49559 "EHLO mail-wg0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750860AbaDXHM5 (ORCPT ); Thu, 24 Apr 2014 03:12:57 -0400 Received: by mail-wg0-f52.google.com with SMTP id b13so625167wgh.23 for ; Thu, 24 Apr 2014 00:12:56 -0700 (PDT) Message-ID: <5358B975.4020207@dev.mellanox.co.il> Date: Thu, 24 Apr 2014 10:12:53 +0300 From: Sagi Grimberg MIME-Version: 1.0 To: Devesh Sharma , Chuck Lever CC: Linux NFS Mailing List , "linux-rdma@vger.kernel.org" , Trond Myklebust Subject: Re: [PATCH V1] NFS-RDMA: fix qp pointer validation checks References: <014738b6-698e-4ea1-82f9-287378bfec19@CMEXHTCAS2.ad.emulex.com> <56C87770-7940-4006-948C-FEF3C0EC4ACC@oracle.com> <5710A71F-C4D5-408B-9B41-07F21B5853F0@oracle.com> <6837A427-B677-4CC7-A022-4FB9E52A3FC6@oracle.com> <1bab6615-60c4-4865-a6a0-c53bb1c32341@CMEXHTCAS1.ad.emulex.com> In-Reply-To: <1bab6615-60c4-4865-a6a0-c53bb1c32341@CMEXHTCAS1.ad.emulex.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Sender: linux-nfs-owner@vger.kernel.org List-ID: On 4/24/2014 2:30 AM, Devesh Sharma wrote: > Hi Chuck > > Following is the complete call trace of a typical NFS-RDMA transaction while mounting a share. > It is unavoidable to stop calling post-send in case it is not created. Therefore, applying checks to the connection state is a must > While registering/deregistering frmrs on-the-fly. The unconnected state of QP implies don't call post_send/post_recv from any context. > Long thread... didn't follow it all. If I understand correctly this race comes only for *cleanup* (LINV) of FRMR registration while teardown flow destroyed the QP. I think this might be disappear if for each registration you post LINV+FRMR. This is assuming that a situation where trying to post Fastreg on a "bad" QP can never happen (usually since teardown flow typically suspends outgoing commands). Sagi.