netpoll: use GFP_ATOMIC in slave_enable_netpoll() and __netpoll_setup()

slave_enable_netpoll() and __netpoll_setup() may be called
with read_lock() held, so should use GFP_ATOMIC to allocate
memory. Eric suggested to pass gfp flags to __netpoll_setup().

Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

5 files changed, 17 insertions, 16 deletions

diff --git a/net/8021q/vlan_dev.c b/net/8021q/vlan_dev.c
index 73a2a83ee2da..ee4ae0944cef 100644
--- a/net/8021q/vlan_dev.c
+++ b/net/8021q/vlan_dev.c
@@ -669,19 +669,20 @@ static void vlan_dev_poll_controller(struct net_device *dev)
         return;
 }
 
-static int vlan_dev_netpoll_setup(struct net_device *dev, struct netpoll_info *npinfo)
+static int vlan_dev_netpoll_setup(struct net_device *dev, struct netpoll_info *npinfo,
+                                  gfp_t gfp)
 {
         struct vlan_dev_priv *info = vlan_dev_priv(dev);
         struct net_device *real_dev = info->real_dev;
         struct netpoll *netpoll;
         int err = 0;
 
-        netpoll = kzalloc(sizeof(*netpoll), GFP_KERNEL);
+        netpoll = kzalloc(sizeof(*netpoll), gfp);
         err = -ENOMEM;
         if (!netpoll)
                 goto out;
 
-        err = __netpoll_setup(netpoll, real_dev);
+        err = __netpoll_setup(netpoll, real_dev, gfp);
         if (err) {
                 kfree(netpoll);
                 goto out;
diff --git a/net/bridge/br_device.c b/net/bridge/br_device.c
index 333484537600..ed0e0f9dc788 100644
--- a/net/bridge/br_device.c
+++ b/net/bridge/br_device.c
@@ -213,7 +213,8 @@ static void br_netpoll_cleanup(struct net_device *dev)
         }
 }
 
-static int br_netpoll_setup(struct net_device *dev, struct netpoll_info *ni)
+static int br_netpoll_setup(struct net_device *dev, struct netpoll_info *ni,
+                            gfp_t gfp)
 {
         struct net_bridge *br = netdev_priv(dev);
         struct net_bridge_port *p, *n;
@@ -222,8 +223,7 @@ static int br_netpoll_setup(struct net_device *dev, struct netpoll_info *ni)
         list_for_each_entry_safe(p, n, &br->port_list, list) {
                 if (!p->dev)
                         continue;
-
-                err = br_netpoll_enable(p);
+                err = br_netpoll_enable(p, gfp);
                 if (err)
                         goto fail;
         }
@@ -236,17 +236,17 @@ fail:
         goto out;
 }
 
-int br_netpoll_enable(struct net_bridge_port *p)
+int br_netpoll_enable(struct net_bridge_port *p, gfp_t gfp)
 {
         struct netpoll *np;
         int err = 0;
 
-        np = kzalloc(sizeof(*p->np), GFP_KERNEL);
+        np = kzalloc(sizeof(*p->np), gfp);
         err = -ENOMEM;
         if (!np)
                 goto out;
 
-        err = __netpoll_setup(np, p->dev);
+        err = __netpoll_setup(np, p->dev, gfp);
         if (err) {
                 kfree(np);
                 goto out;
diff --git a/net/bridge/br_if.c b/net/bridge/br_if.c
index e1144e1617be..171fd6b9bfe6 100644
--- a/net/bridge/br_if.c
+++ b/net/bridge/br_if.c
@@ -361,7 +361,7 @@ int br_add_if(struct net_bridge *br, struct net_device *dev)
         if (err)
                 goto err2;
 
-        if (br_netpoll_info(br) && ((err = br_netpoll_enable(p))))
+        if (br_netpoll_info(br) && ((err = br_netpoll_enable(p, GFP_KERNEL))))
                 goto err3;
 
         err = netdev_set_master(dev, br->dev);
diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
index a768b2408edf..f507d2af9646 100644
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h
@@ -316,7 +316,7 @@ static inline void br_netpoll_send_skb(const struct net_bridge_port *p,
                 netpoll_send_skb(np, skb);
 }
 
-extern int br_netpoll_enable(struct net_bridge_port *p);
+extern int br_netpoll_enable(struct net_bridge_port *p, gfp_t gfp);
 extern void br_netpoll_disable(struct net_bridge_port *p);
 #else
 static inline struct netpoll_info *br_netpoll_info(struct net_bridge *br)
@@ -329,7 +329,7 @@ static inline void br_netpoll_send_skb(const struct net_bridge_port *p,
 {
 }
 
-static inline int br_netpoll_enable(struct net_bridge_port *p)
+static inline int br_netpoll_enable(struct net_bridge_port *p, gfp_t gfp)
 {
         return 0;
 }
diff --git a/net/core/netpoll.c b/net/core/netpoll.c
index b4c90e42b443..37cc854774a4 100644
--- a/net/core/netpoll.c
+++ b/net/core/netpoll.c
@@ -715,7 +715,7 @@ int netpoll_parse_options(struct netpoll *np, char *opt)
 }
 EXPORT_SYMBOL(netpoll_parse_options);
 
-int __netpoll_setup(struct netpoll *np, struct net_device *ndev)
+int __netpoll_setup(struct netpoll *np, struct net_device *ndev, gfp_t gfp)
 {
         struct netpoll_info *npinfo;
         const struct net_device_ops *ops;
@@ -734,7 +734,7 @@ int __netpoll_setup(struct netpoll *np, struct net_device *ndev)
         }
 
         if (!ndev->npinfo) {
-                npinfo = kmalloc(sizeof(*npinfo), GFP_KERNEL);
+                npinfo = kmalloc(sizeof(*npinfo), gfp);
                 if (!npinfo) {
                         err = -ENOMEM;
                         goto out;
@@ -752,7 +752,7 @@ int __netpoll_setup(struct netpoll *np, struct net_device *ndev)
 
                 ops = np->dev->netdev_ops;
                 if (ops->ndo_netpoll_setup) {
-                        err = ops->ndo_netpoll_setup(ndev, npinfo);
+                        err = ops->ndo_netpoll_setup(ndev, npinfo, gfp);
                         if (err)
                                 goto free_npinfo;
                 }
@@ -857,7 +857,7 @@ int netpoll_setup(struct netpoll *np)
         refill_skbs();
 
         rtnl_lock();
-        err = __netpoll_setup(np, ndev);
+        err = __netpoll_setup(np, ndev, GFP_KERNEL);
         rtnl_unlock();
 
         if (err)