Subject: [PATCH net 2/3] hv_netvsc: fix network namespace issues with VF support

From: Stephen Hemminger <[email-masked]>
Date: Mon, 11 Jun 2018 12:44:55 -0700

When finding the parent netvsc device, the search needs to be across
all netvsc device instances (independent of network namespace).

Find parent device of VF using upper_dev_get routine which
searches only adjacent list.

Fixes: e8ff40d4bff1 ("hv_netvsc: improve VF device matching")
Signed-off-by: Stephen Hemminger <[email-masked]>

netns aware byref
---
 drivers/net/hyperv/hyperv_net.h |  2 ++
 drivers/net/hyperv/netvsc_drv.c | 43 +++++++++++++++------------------
 2 files changed, 22 insertions(+), 23 deletions(-)

diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h
index 1be34d2e3563..c0b3f3c125d4 100644
--- a/drivers/net/hyperv/hyperv_net.h
+++ b/drivers/net/hyperv/hyperv_net.h
@@ -902,6 +902,8 @@ struct net_device_context {
 	struct hv_device *device_ctx;
 	/* netvsc_device */
 	struct netvsc_device __rcu *nvdev;
+	/* list of netvsc net_devices */
+	struct list_head list;
 	/* reconfigure work */
 	struct delayed_work dwork;
 	/* last reconfig time */
diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index 2d4370c94b6e..8cb21e013d1d 100644
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -69,6 +69,8 @@ static int debug = -1;
 module_param(debug, int, 0444);
 MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)");
 
+static LIST_HEAD(netvsc_dev_list);
+
 static void netvsc_change_rx_flags(struct net_device *net, int change)
 {
 	struct net_device_context *ndev_ctx = netdev_priv(net);
@@ -1783,13 +1785,10 @@ static void netvsc_link_change(struct work_struct *w)
 
 static struct net_device *get_netvsc_bymac(const u8 *mac)
 {
-	struct net_device *dev;
-
-	ASSERT_RTNL();
+	struct net_device_context *ndev_ctx;
 
-	for_each_netdev(&init_net, dev) {
-		if (dev->netdev_ops != &device_ops)
-			continue;	/* not a netvsc device */
+	list_for_each_entry(ndev_ctx, &netvsc_dev_list, list) {
+		struct net_device *dev = hv_get_drvdata(ndev_ctx->device_ctx);
 
 		if (ether_addr_equal(mac, dev->perm_addr))
 			return dev;
@@ -1800,25 +1799,18 @@ static struct net_device *get_netvsc_bymac(const u8 *mac)
 
 static struct net_device *get_netvsc_byref(struct net_device *vf_netdev)
 {
+	struct net_device_context *net_device_ctx;
 	struct net_device *dev;
 
-	ASSERT_RTNL();
-
-	for_each_netdev(&init_net, dev) {
-		struct net_device_context *net_device_ctx;
+	dev = netdev_master_upper_dev_get(vf_netdev);
+	if (!dev || dev->netdev_ops != &device_ops)
+		return NULL;	/* not a netvsc device */
 
-		if (dev->netdev_ops != &device_ops)
-			continue;	/* not a netvsc device */
+	net_device_ctx = netdev_priv(dev);
+	if (!rtnl_dereference(net_device_ctx->nvdev))
+		return NULL;	/* device is removed */
 
-		net_device_ctx = netdev_priv(dev);
-		if (!rtnl_dereference(net_device_ctx->nvdev))
-			continue;	/* device is removed */
-
-		if (rtnl_dereference(net_device_ctx->vf_netdev) == vf_netdev)
-			return dev;	/* a match */
-	}
-
-	return NULL;
+	return dev;
 }
 
 /* Called when VF is injecting data into network stack.
@@ -2095,15 +2087,19 @@ static int netvsc_probe(struct hv_device *dev,
 	else
 		net->max_mtu = ETH_DATA_LEN;
 
-	ret = register_netdev(net);
+	rtnl_lock();
+	ret = register_netdevice(net);
 	if (ret != 0) {
 		pr_err("Unable to register netdev.\n");
 		goto register_failed;
 	}
 
-	return ret;
+	list_add(&net_device_ctx->list, &netvsc_dev_list);
+	rtnl_unlock();
+	return 0;
 
 register_failed:
+	rtnl_unlock();
 	rndis_filter_device_remove(dev, nvdev);
 rndis_failed:
 	free_percpu(net_device_ctx->vf_stats);
@@ -2149,6 +2145,7 @@ static int netvsc_remove(struct hv_device *dev)
 		rndis_filter_device_remove(dev, nvdev);
 
 	unregister_netdevice(net);
+	list_del(&ndev_ctx->list);
 
 	rtnl_unlock();
 	rcu_read_unlock();
-- 
2.17.1