From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933741AbeB1TVj (ORCPT ); Wed, 28 Feb 2018 14:21:39 -0500 Received: from mx2.suse.de ([195.135.220.15]:43037 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933424AbeB1TVc (ORCPT ); Wed, 28 Feb 2018 14:21:32 -0500 Subject: Re: [PATCH] xen-netfront: Fix hang on device removal To: Jason Andryuk , xen-devel@lists.xenproject.org, netdev@vger.kernel.org Cc: Eduardo Otubo , Boris Ostrovsky , open list References: <20180228122323.3914-1-jandryuk@gmail.com> From: Juergen Gross Message-ID: Date: Wed, 28 Feb 2018 20:21:30 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: <20180228122323.3914-1-jandryuk@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Language: de-DE Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 28/02/18 13:23, Jason Andryuk wrote: > A toolstack may delete the vif frontend and backend xenstore entries > while xen-netfront is in the removal code path. In that case, the > checks for xenbus_read_driver_state would return XenbusStateUnknown, and > xennet_remove would hang indefinitely. This hang prevents system > shutdown. > > xennet_remove must be able to handle XenbusStateUnknown, and > netback_changed must also wake up the wake_queue for that state as well. > > Fixes: 5b5971df3bc2 ("xen-netfront: remove warning when unloading module") > > Signed-off-by: Jason Andryuk > Cc: Eduardo Otubo Committed to xen/tip for-linus-4.16a Juergen