Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756458AbdGCOb0 (ORCPT ); Mon, 3 Jul 2017 10:31:26 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:36274 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932576AbdGCNnN (ORCPT ); Mon, 3 Jul 2017 09:43:13 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Igor Druzhinin , Wei Liu , Paul Durrant , "David S. Miller" , Sasha Levin Subject: [PATCH 4.9 075/172] xen-netback: protect resource cleaning on XenBus disconnect Date: Mon, 3 Jul 2017 15:34:15 +0200 Message-Id: <20170703133417.740924676@linuxfoundation.org> X-Mailer: git-send-email 2.13.2 In-Reply-To: <20170703133414.260777365@linuxfoundation.org> References: <20170703133414.260777365@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2228 Lines: 70 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Igor Druzhinin [ Upstream commit f16f1df65f1cf139ff9e9f84661e6573d6bb27fc ] vif->lock is used to protect statistics gathering agents from using the queue structure during cleaning. Signed-off-by: Igor Druzhinin Acked-by: Wei Liu Reviewed-by: Paul Durrant Signed-off-by: David S. Miller Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/net/xen-netback/interface.c | 6 ++++-- drivers/net/xen-netback/xenbus.c | 2 ++ 2 files changed, 6 insertions(+), 2 deletions(-) --- a/drivers/net/xen-netback/interface.c +++ b/drivers/net/xen-netback/interface.c @@ -221,18 +221,18 @@ static struct net_device_stats *xenvif_g { struct xenvif *vif = netdev_priv(dev); struct xenvif_queue *queue = NULL; - unsigned int num_queues = vif->num_queues; unsigned long rx_bytes = 0; unsigned long rx_packets = 0; unsigned long tx_bytes = 0; unsigned long tx_packets = 0; unsigned int index; + spin_lock(&vif->lock); if (vif->queues == NULL) goto out; /* Aggregate tx and rx stats from each queue */ - for (index = 0; index < num_queues; ++index) { + for (index = 0; index < vif->num_queues; ++index) { queue = &vif->queues[index]; rx_bytes += queue->stats.rx_bytes; rx_packets += queue->stats.rx_packets; @@ -241,6 +241,8 @@ static struct net_device_stats *xenvif_g } out: + spin_unlock(&vif->lock); + vif->dev->stats.rx_bytes = rx_bytes; vif->dev->stats.rx_packets = rx_packets; vif->dev->stats.tx_bytes = tx_bytes; --- a/drivers/net/xen-netback/xenbus.c +++ b/drivers/net/xen-netback/xenbus.c @@ -503,9 +503,11 @@ static void backend_disconnect(struct ba for (queue_index = 0; queue_index < be->vif->num_queues; ++queue_index) xenvif_deinit_queue(&be->vif->queues[queue_index]); + spin_lock(&be->vif->lock); vfree(be->vif->queues); be->vif->num_queues = 0; be->vif->queues = NULL; + spin_unlock(&be->vif->lock); xenvif_disconnect_ctrl(be->vif); }