Return-Path: Received: from mx144.netapp.com ([216.240.21.25]:25344 "EHLO mx144.netapp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751129AbcJZSR3 (ORCPT ); Wed, 26 Oct 2016 14:17:29 -0400 Subject: Re: nfs NULL-dereferencing in net-next To: Jakub Kicinski References: <20161017201943.64529739@jkicinski-Precision-T1700> <817e43c5-d88d-e616-7074-5715de29d319@Netapp.com> <20161026190840.3d46dad8@jkicinski-Precision-T1700> CC: Yotam Gigi , Andy Adamson , "linux-nfs@vger.kernel.org" , "netdev@vger.kernel.org" , Trond Myklebust , Yotam Gigi , mlxsw From: Anna Schumaker Message-ID: <0ab5021c-84eb-cb9f-c7f5-4d856fdb0f4b@Netapp.com> Date: Wed, 26 Oct 2016 14:17:14 -0400 MIME-Version: 1.0 In-Reply-To: <20161026190840.3d46dad8@jkicinski-Precision-T1700> Content-Type: text/plain; charset="utf-8" Sender: linux-nfs-owner@vger.kernel.org List-ID: On 10/26/2016 02:08 PM, Jakub Kicinski wrote: > On Wed, 26 Oct 2016 16:15:24 +0000, Yotam Gigi wrote: >>> -----Original Message----- >>> From: Anna Schumaker [mailto:Anna.Schumaker@Netapp.com] >>> Sent: Wednesday, October 26, 2016 5:40 PM >>> To: Yotam Gigi ; Jakub Kicinski ; Andy >>> Adamson ; Anna Schumaker >>> ; linux-nfs@vger.kernel.org >>> Cc: netdev@vger.kernel.org; Trond Myklebust ; >>> Yotam Gigi ; mlxsw >>> Subject: Re: nfs NULL-dereferencing in net-next >>> >>> On 10/25/2016 01:19 PM, Yotam Gigi wrote: >>>> >>>>> -----Original Message----- >>>>> From: netdev-owner@vger.kernel.org [mailto:netdev-owner@vger.kernel.org] >>> On >>>>> Behalf Of Jakub Kicinski >>>>> Sent: Monday, October 17, 2016 10:20 PM >>>>> To: Andy Adamson ; Anna Schumaker >>>>> ; linux-nfs@vger.kernel.org >>>>> Cc: netdev@vger.kernel.org; Trond Myklebust >>> >>>>> Subject: nfs NULL-dereferencing in net-next >>>>> >>>>> Hi! >>>>> >>>>> I'm hitting this reliably on net-next, HEAD at 3f3177bb680f >>>>> ("fsl/fman: fix error return code in mac_probe()"). >>>> >>>> >>>> I see the same thing. It happens constantly on some of my machines, making >>> them >>>> completely unusable. >>>> >>>> I bisected it and got to the commit: >>>> >>>> commit 04ea1b3e6d8ed4978bb608c1748530af3de8c274 >>>> Author: Andy Adamson >>>> Date: Fri Sep 9 09:22:27 2016 -0400 >>>> >>>> NFS add xprt switch addrs test to match client >>>> >>>> Signed-off-by: Andy Adamson >>>> Signed-off-by: Anna Schumaker >>> >>> Thanks for reporting on this everyone! Does this patch help? >> >> Actually, I still see the same bug with the same trace. Well, it was worth a shot. I'll keep poking at it. > > I rebuild the latest net-next and I'm not seeing the trace any more... > I'm only seeing this (with or without your patch): > > [ 23.465877] NFS: set_pnfs_layoutdriver: cl_exchange_flags 0x0 > [ 23.473784] NFS: set_pnfs_layoutdriver: cl_exchange_flags 0x0 > [ 23.588890] NFS: set_pnfs_layoutdriver: cl_exchange_flags 0x0 > [ 23.596746] NFS: set_pnfs_layoutdriver: cl_exchange_flags 0x0 > [ 23.781574] NFS: set_pnfs_layoutdriver: cl_exchange_flags 0x0 > [ 23.789599] NFS: set_pnfs_layoutdriver: cl_exchange_flags 0x0 Interesting, I get that too when I try to use NFS v4.1. It's weird that the crash would stop happening like that, so maybe something is racy in this area. Thanks for testing, Yotam and Jakub! Anna > > HTH >