Re: [PATCH] xen-netback: fix memory leaks on XenBus disconnect
From: Wei Liu <hidden>
Date: 2017-01-13 10:38:04
Also in:
lkml
On Thu, Jan 12, 2017 at 05:51:56PM +0000, Igor Druzhinin wrote:
Eliminate memory leaks introduced several years ago by cleaning the queue resources which are allocated on XenBus connection event. Namely, queue structure array and pages used for IO rings. vif->lock is used to protect statistics gathering agents from using the queue structure during cleaning.
There is code in netback_remove which eventually calls xenvif_free to free up the resources, maybe you should modify xenvif_free instead? That seems more symmetric to me. What do you think?
quoted hunk ↗ jump to hunk
Signed-off-by: Igor Druzhinin <redacted> --- drivers/net/xen-netback/interface.c | 6 ++++-- drivers/net/xen-netback/xenbus.c | 13 +++++++++++++ 2 files changed, 17 insertions(+), 2 deletions(-)diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c index e30ffd2..5795213 100644 --- a/drivers/net/xen-netback/interface.c +++ b/drivers/net/xen-netback/interface.c@@ -221,18 +221,18 @@ 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;@@ -241,6 +241,8 @@ static struct net_device_stats *xenvif_get_stats(struct net_device *dev) } out: + spin_unlock(&vif->lock); +
Good catch, this is definitely needed. And it would probably be in a separate patch. Wei.