From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 09340ECDE30 for ; Wed, 17 Oct 2018 14:47:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C2F7721531 for ; Wed, 17 Oct 2018 14:47:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="Jk5rL/VA" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C2F7721531 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727678AbeJQWnb (ORCPT ); Wed, 17 Oct 2018 18:43:31 -0400 Received: from mail.kernel.org ([198.145.29.99]:36176 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727410AbeJQWnb (ORCPT ); Wed, 17 Oct 2018 18:43:31 -0400 Received: from localhost (unknown [46.144.157.90]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 6C0DE2151D; Wed, 17 Oct 2018 14:47:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1539787648; bh=ZQsVGQF7ZECPiHpQfhns92/hstfX+CGLdomYDiqibsY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Jk5rL/VAAjwMiQBXMFzuKAKolBiUkVxl6hUZK0aAV88pzV7bHxC4BS7noFxDrt9fW rRFp3ZhzKlOpl6nmIpxCkFJvsKHuQoy87LpIuTv1fAn8j6+QFmvQOnrMnsl2SC+mCD s7upkwQD/y0+1mFc/TkQWrH+Ok2DCWbxqBIciHDg= Date: Wed, 17 Oct 2018 16:47:25 +0200 From: Greg Kroah-Hartman To: Sasha Levin Cc: Haiyang Zhang , "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" , Stephen Hemminger , "David S. Miller" , Sasha Levin Subject: Re: [PATCH 4.18 101/135] hv_netvsc: pair VF based on serial number Message-ID: <20181017144725.GB3094@kroah.com> References: <20181016170515.447235311@linuxfoundation.org> <20181016170522.303317746@linuxfoundation.org> <20181017074629.GD25537@kroah.com> <20181017131717.GA10130@kroah.com> <20181017142621.GB366@kroah.com> <20181017144034.GB135013@sasha-vm> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181017144034.GB135013@sasha-vm> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 17, 2018 at 10:40:34AM -0400, Sasha Levin wrote: > On Wed, Oct 17, 2018 at 04:26:21PM +0200, Greg Kroah-Hartman wrote: > > On Wed, Oct 17, 2018 at 02:15:30PM +0000, Haiyang Zhang wrote: > > > The VF NIC needs to be paired with synthetic NIC on HyperV -- to do that we > > > use MAC address matching before the patch #A. But a non VF NIC can also > > > have the same MAC, which shouldn't be paired with synthetic NIC. So a better > > > method is implemented by #A to use VF serial number for matching. > > > > > > But, #A has a bug, which causes matching to fail. Patch #B fixed it by extracting > > > the VF serial number correctly from slot info. > > > > My question is, "what bug is patch #A fixing"? Somehow things have been > > working just fine for people without this, right? Remember, new > > features should not be backported to stable kernels if at all possible. > > The current mechanism works fine most of the time, the problem is that > once in a while we'd see collisions between the synthetic device MAC > address and a different network device such as a bond device or just a > regular non-VF network device. > > So while in most cases assuming that MAC is unique and looking up > devices based on it works, there's no guarantee that it's unique so > this assumption isn't true and things break. > > This is why it (usually) works now, but still has a bug that needs > fixing. > > If that makes sense, I'll requeue it when the fixes have soaked upstream > for a few weeks. That does, thanks, it should have been in the first patch's original changelog comments :) So when both are upstream, feel free to resend. thanks, greg k-h