From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757385Ab3JODPV (ORCPT ); Mon, 14 Oct 2013 23:15:21 -0400 Received: from mx1.redhat.com ([209.132.183.28]:53702 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756226Ab3JODPU (ORCPT ); Mon, 14 Oct 2013 23:15:20 -0400 Message-ID: <525CB33A.4080103@redhat.com> Date: Tue, 15 Oct 2013 11:15:06 +0800 From: Jason Wang User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.0 MIME-Version: 1.0 To: "Michael S. Tsirkin" CC: virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, rusty@rustcorp.com.au Subject: Re: [PATCH net 2/2] virtio-net: refill only when device is up during setting queues References: <1381744595-26881-1-git-send-email-jasowang@redhat.com> <1381744595-26881-2-git-send-email-jasowang@redhat.com> <20131014110951.GG30954@redhat.com> In-Reply-To: <20131014110951.GG30954@redhat.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/14/2013 07:09 PM, Michael S. Tsirkin wrote: > On Mon, Oct 14, 2013 at 05:56:35PM +0800, Jason Wang wrote: >> > We used to schedule the refill work unconditionally after changing the >> > number of queues. This may lead an issue if the device is not >> > up. Since we only try to cancel the work in ndo_stop(), this may cause >> > the refill work still work after removing the device. Fix this by only >> > schedule the work when device is up. >> > >> > The bug were introduce by commit 9b9cd8024a2882e896c65222aa421d461354e3f2. >> > (virtio-net: fix the race between channels setting and refill) >> > >> > Cc: Rusty Russell >> > Cc: Michael S. Tsirkin >> > Signed-off-by: Jason Wang > It bothers me that we look at the flag without any > locks here. > I think we'll need to take the rtnl lock at least > on restore. > True, will post v2.