The patch below does not apply to the 2.6.39-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.
thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 9079ce691255792009c446d8c3382507b8d38635 Mon Sep 17 00:00:00 2001 From: "K. Y. Srinivasan" <[email protected]> Date: Thu, 16 Jun 2011 13:16:37 -0700 Subject: [PATCH] Staging: hv: netvsc: Fix a bug in accounting transmit slots The transmit slots were manipulated without proper locking. Fix this bug by making the variable tracking the transmit slots atomic. This patch should be ported to prior stable kernels 2.6.32 and later. Signed-off-by: K. Y. Srinivasan <[email protected]> Signed-off-by: Haiyang Zhang <[email protected]> Signed-off-by: Hank Janssen <[email protected]> Cc: stable <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> 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); _______________________________________________ stable mailing list [email protected] http://linux.kernel.org/mailman/listinfo/stable
