This is a note to let you know that I've just added the patch titled xen-netback: protect resource cleaning on XenBus disconnect to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: xen-netback-protect-resource-cleaning-on-xenbus-disconnect.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Mon Jul 3 11:54:13 CEST 2017 From: Igor Druzhinin <igor.druzhinin@xxxxxxxxxx> Date: Tue, 17 Jan 2017 20:49:38 +0000 Subject: xen-netback: protect resource cleaning on XenBus disconnect From: Igor Druzhinin <igor.druzhinin@xxxxxxxxxx> [ Upstream commit f16f1df65f1cf139ff9e9f84661e6573d6bb27fc ] vif->lock is used to protect statistics gathering agents from using the queue structure during cleaning. Signed-off-by: Igor Druzhinin <igor.druzhinin@xxxxxxxxxx> Acked-by: Wei Liu <wei.liu2@xxxxxxxxxx> Reviewed-by: Paul Durrant <paul.durrant@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- 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); } Patches currently in stable-queue which might be from igor.druzhinin@xxxxxxxxxx are queue-4.9/xen-netback-protect-resource-cleaning-on-xenbus-disconnect.patch queue-4.9/xen-netback-fix-memory-leaks-on-xenbus-disconnect.patch