From mboxrd@z Thu Jan 1 00:00:00 1970 From: Robert Shearman Subject: Re: /net/mpls/conf/ethX//input duplicate entry Date: Thu, 11 Jun 2015 13:55:48 +0100 Message-ID: <55798554.7020102@brocade.com> References: <5578B318.1050808@cumulusnetworks.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit Cc: Netdev , "ebiederm@xmission.com" To: Scott Feldman , roopa Return-path: Received: from mx0a-000f0801.pphosted.com ([67.231.144.122]:35885 "EHLO mx0a-000f0801.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933618AbbFKM4t (ORCPT ); Thu, 11 Jun 2015 08:56:49 -0400 In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On 11/06/15 00:23, Scott Feldman wrote: > On Wed, Jun 10, 2015 at 2:58 PM, roopa wrote: >> On 6/10/15, 1:43 PM, Scott Feldman wrote: >>> >>> I'm getting this dump_stack when reloading rocker driver. Did some >>> sysctl MPLS nodes not get cleaned up on NETDEV_UNREGISTER? >>> >>> Steps to repro: load rocker (on system) with rocker device, rmmod >>> rocker, and then modprobe rocker. I doubt this is specific to rocker: >>> and re-registration of a netdev should hit it. I am using UDEV rules >>> to rename kernel's ethX to a different name. Maybe that's what >>> tripped it up? >>> >> On a quick look, wondering if this is because mpls driver does not seem to >> do a unregister and re-register sysctl >> on device name change. Mea culpa. Thanks for looking at this. >> >> diff --git a/net/mpls/af_mpls.c b/net/mpls/af_mpls.c >> index 7b3f732..ec21a5d 100644 >> --- a/net/mpls/af_mpls.c >> +++ b/net/mpls/af_mpls.c >> @@ -564,6 +564,14 @@ static int mpls_dev_notify(struct notifier_block *this, >> unsigned long event, >> case NETDEV_UNREGISTER: >> mpls_ifdown(dev); >> break; >> + case NETDEV_CHANGENAME: >> + mpls_ifdown(dev); >> + if ((dev->type == ARPHRD_ETHER) || >> + (dev->type == ARPHRD_LOOPBACK)) { >> + mdev = mpls_add_dev(dev); >> + if (IS_ERR(mdev)) >> + return notifier_from_errno(PTR_ERR(mdev)); >> + } >> } >> return NOTIFY_OK; >> } > > Roopa, I tested this patch and problem goes away. (It's missing a > break statement, BTW). I didn't look into the correctness of the > patch, but at first glance it seems liek the right thing to do. Maybe > breaking out the renaming portions into sub-functions could keep the > work done in NETDEV_CHANGENAME to a minimum. I agree that breaking out the sysctl registration/unregistration is a good idea to not have to do more work than is necessary, and to avoid unintended consequences (like routes using the interface being made unusable). > > Are you sending official fix? Roopa, let me know if you'd like me to carry this forward. Thanks, Rob