From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vlad Yasevich Subject: Re: [PATCH net 5/6] rtnetlink: check DO_SETLINK_NOTIFY correctly in do_setlink Date: Thu, 26 Oct 2017 08:52:48 +0200 Message-ID: <0e37130c-bbf3-c75e-5cee-c3a08206873f@redhat.com> References: <784f477a1f9e8b9a5ec7bbe9e1dff1dcdfd5553b.1508062280.git.lucien.xin@gmail.com> <22c0aefe18d4451166c5f12714d8520346a63f2b.1508062280.git.lucien.xin@gmail.com> Reply-To: vyasevic@redhat.com Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Cc: davem@davemloft.net, hannes@stressinduktion.org To: nicolas.dichtel@6wind.com, David Ahern , Xin Long , network dev Return-path: Received: from mx1.redhat.com ([209.132.183.28]:58562 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751229AbdJZGwy (ORCPT ); Thu, 26 Oct 2017 02:52:54 -0400 In-Reply-To: Content-Language: en-US Sender: netdev-owner@vger.kernel.org List-ID: On 10/16/2017 02:20 PM, Nicolas Dichtel wrote: > Le 16/10/2017 à 03:17, David Ahern a écrit : >> [ cc'ed Nicolas ] >> >> On 10/15/17 4:13 AM, Xin Long wrote: >>> The check 'status & DO_SETLINK_NOTIFY' in do_setlink doesn't really >>> work after status & DO_SETLINK_MODIFIED, as: >>> >>> DO_SETLINK_MODIFIED 0x1 >>> DO_SETLINK_NOTIFY 0x3 >>> >>> Considering that notifications are suppposed to be sent only when >>> status have the flag DO_SETLINK_NOTIFY, the right check would be: >>> >>> (status & DO_SETLINK_NOTIFY) == DO_SETLINK_NOTIFY >>> >>> This would avoid lots of duplicated notifications when setting some >>> properties of a link. >>> >>> Fixes: ba9989069f4e ("rtnl/do_setlink(): notify when a netdev is modified") >>> Signed-off-by: Xin Long > Good catch, thank you. > > Acked-by: Nicolas Dichtel > So I found this the first timer around when looking at this code, but was told that notification are expected anytime we modified any setting thus the code was simply checking for MODIFIED bit. Has that thinking changed? -vlad