Re: [PATCH v2 2/2] xen-netback: protect resource cleaning on XenBus disconnect
From: Paul Durrant <hidden>
Date: 2017-01-18 09:46:54
Also in:
lkml, xen-devel
-----Original Message----- From: Igor Druzhinin [mailto:igor.druzhinin@citrix.com] Sent: 17 January 2017 20:50 To: Wei Liu <redacted> Cc: Paul Durrant <redacted>; xen-devel@lists.xenproject.org; netdev@vger.kernel.org; linux-kernel@vger.kernel.org; Igor Druzhinin [off-list ref] Subject: [PATCH v2 2/2] xen-netback: protect resource cleaning on XenBus disconnect vif->lock is used to protect statistics gathering agents from using the queue structure during cleaning. Signed-off-by: Igor Druzhinin <redacted>
Reviewed-by: Paul Durrant <redacted>
quoted hunk ↗ jump to hunk
--- drivers/net/xen-netback/interface.c | 6 ++++-- drivers/net/xen-netback/xenbus.c | 2 ++ 2 files changed, 6 insertions(+), 2 deletions(-)diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c index 41c69b3..c48252a 100644--- a/drivers/net/xen-netback/interface.c +++ b/drivers/net/xen-netback/interface.c@@ -230,18 +230,18 @@ static struct net_device_stats*xenvif_get_stats(struct net_device *dev) { 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;@@ -250,6 +250,8 @@ static struct net_device_stats*xenvif_get_stats(struct net_device *dev) } 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;diff --git a/drivers/net/xen-netback/xenbus.c b/drivers/net/xen-netback/xenbus.c index 3e99071..d82cd71 100644--- a/drivers/net/xen-netback/xenbus.c +++ b/drivers/net/xen-netback/xenbus.c@@ -503,9 +503,11 @@ static void backend_disconnect(struct backend_info*be) for (queue_index = 0; queue_index < be->vif-quoted
num_queues; ++queue_index)xenvif_deinit_queue(&be->vif-quoted
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); } -- 1.8.3.1
_______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org https://lists.xen.org/xen-devel