From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jason Wang Subject: Re: Linux 4.14 - regression: broken tun/tap / bridge network with virtio - bisected Date: Wed, 6 Dec 2017 11:08:41 +0800 Message-ID: References: <9615150a-eb78-2f9d-798f-6aa460932aec@01019freenet.de> <2e2392b7-84c5-be89-b0e5-5bae3b2fdaed@01019freenet.de> <4efbaf24-f419-2c8e-c705-59a5242b0575@01019freenet.de> <881560f8-54ec-e946-50cb-b2e80ddb5f97@01019freenet.de> <73b7a7b0-4264-2bd0-9e65-69841377f09f@redhat.com> <401a0715-fd28-63a3-8dfd-e89835d70db0@01019freenet.de> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Cc: netdev@vger.kernel.org, john.fastabend@gmail.com, Michal Kubecek To: Andreas Hartmann Return-path: Received: from mx1.redhat.com ([209.132.183.28]:58396 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754350AbdLFDIq (ORCPT ); Tue, 5 Dec 2017 22:08:46 -0500 In-Reply-To: <401a0715-fd28-63a3-8dfd-e89835d70db0@01019freenet.de> Content-Language: en-US Sender: netdev-owner@vger.kernel.org List-ID: On 2017年12月06日 00:23, Andreas Hartmann wrote: > On 12/05/2017 at 04:50 AM Jason Wang wrote: >> >> On 2017年12月05日 00:28, Andreas Hartmann wrote: >>> On 12/03/2017 at 12:35 PM Andreas Hartmann wrote: >>>> On 12/01/2017 at 11:11 AM Andreas Hartmann wrote: >>>>> Hello! >>>>> >>>>> I hopefully could get rid of both of my problems (hanging network w/ >>>>> virtio) and endless hanging qemu-process on VM shutdown by upgrading >>>>> qemu from 2.6.2 to 2.10.1. I hope it will persist. >>>> It didn't persist. 10h later - same problems happened again. It's just >>>> much harder to trigger the problems. >>>> >>>> I'm now trying it with >>>> >>>> CONFIG_RCU_NOCB_CPU=y and >>>> rcu_nocbs=0-15 >>>> >>>> Since then, I didn't see any problem any more. But this doesn't mean >>>> anything until now ... . >>> Didn't work ether. Disabling vhost_net's zcopy hadn't any effect, too. >>> >>> => It's just finally broken since >>> >>> 2ddf71e23cc246e95af72a6deed67b4a50a7b81c >>> net: add notifier hooks for devmap bpf map >> Hi: >> >> Did you use XDP devmap in host? If not, please double check it was the >> first bad commit since the patch should only work when XDP/devmap is >> used on host. > How do I know if XDP/devmap is enabled / used? Could you please give > some hint? > > > Thanks, > Andreas Something like: ./ip link | grep xdp 10: tap0: mtu 1500 xdp qdisc mq master kvmbr0 state UNKNOWN mode DEFAULT group default qlen 1000     prog/xdp id 4 tag 0381911915bc8d7f But you should have some recent version of ip. Thanks