From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Gibson Subject: [0/2] Fix problems with with IFLA_VF_PORTS (v2) Date: Thu, 24 Apr 2014 10:22:34 +1000 Message-ID: <1398298956-13084-1-git-send-email-david@gibson.dropbear.id.au> Cc: ssujith@cisco.com, neepatel@cisco.com, benve@cisco.com, davem@davemloft.net, ben@decadent.org.uk, govindarajulu90@gmail.com, gregory.v.rose@intel.com To: netdev@vger.kernel.org Return-path: Received: from ozlabs.org ([103.22.144.67]:53633 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751017AbaDXAWg (ORCPT ); Wed, 23 Apr 2014 20:22:36 -0400 Sender: netdev-owner@vger.kernel.org List-ID: I've had a customer encounter a problem with getifaddrs(3) freezing up on a system with a Cisco enic device. I've discovered that the problem is caused by an enic device with a large number of SR-IOV virtual functions overflowing the normal sized packet buffer for netlink, leading to interfaces not being reported from an RTM_GETLINK request. The first patch here just makes the problem easier to locate if it occurs again in a different way, by adding a WARN_ON() when we run out of room in a netlink packet in this manner. The second patch actually fixes the problem, by only reporting IFLA_VF_PORTS information when the RTEXT_FILTER_VF flag is specified. v2: Corrected some CodingStyle problems