From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCHv1 net] xen-netback: fix guest Rx stall detection (after guest Rx refactor) Date: Thu, 13 Oct 2016 10:21:14 -0400 (EDT) Message-ID: <20161013.102114.277377641513965761.davem@davemloft.net> References: <1476200907-16085-1-git-send-email-david.vrabel@citrix.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, xen-devel@lists.xenproject.org, paul.durrant@citrix.com, wei.liu2@citrix.com To: david.vrabel@citrix.com Return-path: Received: from shards.monkeyblade.net ([184.105.139.130]:33224 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932642AbcJMOWv (ORCPT ); Thu, 13 Oct 2016 10:22:51 -0400 In-Reply-To: <1476200907-16085-1-git-send-email-david.vrabel@citrix.com> Sender: netdev-owner@vger.kernel.org List-ID: From: David Vrabel Date: Tue, 11 Oct 2016 16:48:27 +0100 > If a VIF has been ready for rx_stall_timeout (60s by default) and an > Rx ring is drained of all requests an Rx stall will be incorrectly > detected. When this occurs and the guest Rx queue is empty, the Rx > ring's event index will not be set and the frontend will not raise an > event when new requests are placed on the ring, permanently stalling > the VIF. > > This is a regression introduced by eb1723a29b9a7 (xen-netback: > refactor guest rx). > > Fix this by reinstating the setting of queue->last_rx_time when > placing a packet onto the guest Rx ring. > > Signed-off-by: David Vrabel Applied.