The current code manipulates the available transmit slots without proper locking; fix it.
Signed-off-by: K. Y. Srinivasan <[email protected]> Signed-off-by: Haiyang Zhang <[email protected]> Signed-off-by: Abhishek Kane <[email protected]> --- drivers/staging/hv/netvsc_drv.c | 16 +++++++++------- 1 files changed, 9 insertions(+), 7 deletions(-) diff --git a/drivers/staging/hv/netvsc_drv.c b/drivers/staging/hv/netvsc_drv.c index 33cab9c..38ca2c2 100644 --- a/drivers/staging/hv/netvsc_drv.c +++ b/drivers/staging/hv/netvsc_drv.c @@ -21,6 +21,7 @@ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/init.h> +#include <linux/atomic.h> #include <linux/module.h> #include <linux/highmem.h> #include <linux/device.h> @@ -45,7 +46,7 @@ struct net_device_context { /* point back to our device context */ struct hv_device *device_ctx; - unsigned long avail; + atomic_t avail; struct delayed_work dwork; }; @@ -118,8 +119,9 @@ static void netvsc_xmit_completion(void *context) dev_kfree_skb_any(skb); - net_device_ctx->avail += num_pages; - if (net_device_ctx->avail >= PACKET_PAGES_HIWATER) + atomic_add(num_pages, &net_device_ctx->avail); + if (atomic_read(&net_device_ctx->avail) >= + PACKET_PAGES_HIWATER) netif_wake_queue(net); } } @@ -133,7 +135,7 @@ static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net) /* Add 1 for skb->data and additional one for RNDIS */ num_pages = skb_shinfo(skb)->nr_frags + 1 + 1; - if (num_pages > net_device_ctx->avail) + if (num_pages > atomic_read(&net_device_ctx->avail)) return NETDEV_TX_BUSY; /* Allocate a netvsc packet based on # of frags. */ @@ -185,8 +187,8 @@ static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net) net->stats.tx_bytes += skb->len; net->stats.tx_packets++; - net_device_ctx->avail -= num_pages; - if (net_device_ctx->avail < PACKET_PAGES_LOWATER) + atomic_sub(num_pages, &net_device_ctx->avail); + if (atomic_read(&net_device_ctx->avail) < PACKET_PAGES_LOWATER) netif_stop_queue(net); } else { /* we are shutting down or bus overloaded, just drop packet */ @@ -345,7 +347,7 @@ static int netvsc_probe(struct hv_device *dev) net_device_ctx = netdev_priv(net); net_device_ctx->device_ctx = dev; - net_device_ctx->avail = ring_size; + atomic_set(&net_device_ctx->avail, ring_size); dev_set_drvdata(&dev->device, net); INIT_DELAYED_WORK(&net_device_ctx->dwork, netvsc_send_garp); -- 1.7.4.1 _______________________________________________ Virtualization mailing list [email protected] https://lists.linux-foundation.org/mailman/listinfo/virtualization
